Chapter 5. Making Happy Users
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## Chapter 5. Making Happy Users

It is said that “a day that is without troubles is not fulfilling. Rather, give me a day of troubles well handled so that I can be content with my achievements.”

In the world of computer networks, problems are as varied as the people who create them or experience them. The design of the network implemented in “The 500-User Office” may create problems for some network users. The following lists some of the problems that may occur:

### Caution

A significant number of network administrators have responded to the guidance given here. It should be noted that there are sites that have a single PDC for many hundreds of concurrent network clients. Network bandwidth, network bandwidth utilization, and server load are among the factors that determine the maximum number of Windows clients that can be served by a single domain controller (PDC or BDC) on a network segment. It is possible to operate with only a single PDC over a routed network. What is possible is not necessarily best practice. When Windows client network logons begin to fail with the message that the domain controller cannot be found or that the user account cannot be found (when you know it exists), that may be an indication that the domain controller is overloaded or network bandwidth is overloaded. The guidance given for PDC/BDC ratio to Windows clients is conservative and if followed will minimize problems but it is not absolute.

Users experiencing difficulty logging onto the network

  When a Windows client logs onto the network, many data packets are exchanged between the client and the server that is providing the network logon services. Each request between the client and the server must complete within a specific time limit. This is one of the primary factors that govern the installation of multiple domain controllers (usually called secondary or backup controllers). As a rough rule, there should be one such backup controller for every 30 to 150 clients. The actual limits are determined by network operational characteristics.

  If the domain controller provides only network logon services and all file and print activity is handled by domain member servers, one domain controller per 150 clients on a single network segment may suffice. In any case, it is highly recommended to have a minimum of one domain controller (PDC or BDC) per network segment. It is better to have at least one BDC on the network segment that has a PDC. If the domain controller is also used as a file and print server, the number of clients it can service reliably is reduced, and generally for low powered hardware should not exceed 30 machines (Windows workstations plus domain member servers) per domain controller. Many sites are able to operate with more clients per domain controller, the number of clients that can be supported is limited by the CPU speed, memory and the workload on the Samba server as well as network bandwidth utilization.

Slow logons and log-offs

  Slow logons and log-offs may be caused by many factors that include:

  - Excessive delays in the resolution of a NetBIOS name to its IP address. This may be observed when an overloaded domain controller is also the WINS server. Another cause may be the failure to use a WINS server (this assumes that there is a single network segment).

  - Network traffic collisions due to overloading of the network segment. One short-term workaround to this may be to replace network HUBs with Ethernet switches.

  - Defective networking hardware. Over the past few years, we have seen on the Samba mailing list a significant increase in the number of problems that were traced to a defective network interface controller, a defective HUB or Ethernet switch, or defective cabling. In most cases, it was the erratic nature of the problem that ultimately pointed to the cause of the problem.

  - Excessively large roaming profiles. This type of problem is typically the result of poor user education as well as poor network management. It can be avoided by users not storing huge quantities of email in MS Outlook PST files as well as by not storing files on the desktop. These are old bad habits that require much discipline and vigilance on the part of network management.

  - You should verify that the Windows XP WebClient service is not running. The use of the WebClient service has been implicated in many Windows networking-related problems.

Loss of access to network drives and printer resources

  Loss of access to network resources during client operation may be caused by a number of factors, including:

  - Network overload (typically indicated by a high network collision rate)

  - Server overload

  - Timeout causing the client to close a connection that is in use but has been latent (no traffic) for some time (5 minutes or more)

  - Defective networking hardware

  No matter what the cause, a sudden loss of access to network resources can result in BSOD (blue screen of death) situations that necessitate rebooting of the client workstation. In the case of a mild problem, retrying to access the network drive of the printer may restore operations, but in any case this is a serious problem that may lead to the next problem, data corruption.

Potential data corruption

  Data corruption is one of the most serious problems. It leads to uncertainty, anger, and frustration, and generally precipitates immediate corrective demands. Management response to this type of problem may be rational, as well as highly irrational. There have been cases where management has fired network staff for permitting this situation to occur without immediate correction. There have been situations where perfectly functional hardware was thrown out and replaced, only to find the problem caused by a low-cost network hardware item. There have been cases where server operating systems were replaced, or where Samba was updated, only to later isolate the problem due to defective client software.

In this chapter, you can work through a number of measures that significantly arm you to anticipate and combat network performance issues. You can work through complex and thorny methods to improve the reliability of your network environment, but be warned that all such steps demand the price of complexity.

## Regarding LDAP Directories and Windows Computer Accounts

Computer (machine) accounts can be placed wherever you like in an LDAP directory subject to some constraints that are described in this section.

The POSIX and SambaSAMAccount components of computer (machine) accounts are both used by Samba. That is, machine accounts are treated inside Samba in the same way that Windows NT4/200X treats them. A user account and a machine account are indistinguishable from each other, except that the machine account ends in a $ character, as do trust accounts.

The need for Windows user, group, machine, trust, and other such accounts to be tied to a valid UNIX UID is a design decision that was made a long way back in the history of Samba development. It is unlikely that this decision will be reversed or changed during the remaining life of the Samba-3.x series.

The resolution of a UID from the Windows SID is achieved within Samba through a mechanism that must refer back to the host operating system on which Samba is running. The name service switch (NSS) is the preferred mechanism that shields applications (like Samba) from the need to know everything about every host OS it runs on.

Samba asks the host OS to provide a UID via the “passwd”, “shadow” and “group” facilities in the NSS control (configuration) file. The best tool for achieving this is left up to the UNIX administrator to determine. It is not imposed by Samba. Samba provides winbindd together with its support libraries as one method. It is possible to do this via LDAP, and for that Samba provides the appropriate hooks so that all account entities can be located in an LDAP directory.

For many the weapon of choice is to use the PADL nss_ldap utility. This utility must be configured so that computer accounts can be resolved to a POSIX/UNIX account UID. That is fundamentally an LDAP design question. The information provided on the Samba list and in the documentation is directed at providing working examples only. The design of an LDAP directory is a complex subject that is beyond the scope of this documentation.

## Introduction

You just opened an email from Christine that reads:

Good morning,

A few months ago we sat down to design the network. We discussed the challenges ahead and we all agreed to compromise our design to keep it simple. We knew there would be problems, but anticipated that we would have some time to resolve any issues that might be encountered.

As you now know, we started off on the wrong foot. We have a lot of unhappy users. One of them resigned yesterday afternoon because she was under duress to complete some critical projects. She suffered a blue screen of death situation just as she was finishing four hours of intensive work, all of which was lost. She has a unique requirement that involves storing large files on her desktop. Mary's desktop profile is nearly 1 GB in size. As a result of her desktop configuration, it takes her nearly 15 minutes just to log onto her workstation. But that is not enough. Because all network logon traffic passes over the network links between our buildings, logging on may take three or four attempts due to blue screen problems associated with network timeouts.

A few of us worked to help her out of trouble. We convinced her to stay and promised to fully resolve the difficulties she is facing. We have no choice. We must implement LDAP and set hard limits on what our users can do with their desktops. Otherwise, we face staff losses that can surely do harm to our growth as well as to staff morale. I am sure we can better deal with the consequences of what we know we must do than we can with the unrest we have now.

Stan and I have discussed the current situation. We are resolved to help our users and protect the well being of Abmas. Please acknowledge this advice with consent to proceed as required to regain control of our vital IT operations.

| --Christine

Every compromise has consequences. Having a large routed (i.e., multisegment) network with only a single domain controller is a poor design that has obvious operational effects that may frustrate users. Here is your reply:

Christine, Your diligence and attention to detail are much valued. Stan and I fully support your proposals to resolve the issues. I am confident that your plans fully realized will significantly boost staff morale. Please go ahead with your plans. If you have any problems, please let me know. Please let Stan know what the estimated cost will be so I can approve the expense. Do not wait for approval; I appreciate the urgency.

| --Bob

### Assignment Tasks

The priority of assigned tasks in this chapter is:

1. Implement Backup Domain Controllers (BDCs) in each building. This involves a change from a tdbsam backend that was used in the previous chapter to an LDAP-based backend.

   You can implement a single central LDAP server for this purpose.

2. Rectify the problem of excessive logon times. This involves redirection of folders to network shares as well as modification of all user desktops to exclude the redirected folders from being loaded at login time. You can also create a new default profile that can be used for all new users.

You configure a new MS Windows XP Professional workstation disk image that you roll out to all desktop users. The instructions you have created are followed on a staging machine from which all changes can be carefully tested before inflicting them on your network users.

This is the last network example in which specific mention of printing is made. The example again makes use of the CUPS printing system.

## Dissection and Discussion

The implementation of Samba BDCs necessitates the installation and configuration of LDAP. For this site, you use OpenLDAP, the open source software LDAP server platform. Commercial LDAP servers in current use with Samba-3 include:

- Novell eDirectory is being successfully used by some sites. Information on how to use eDirectory can be obtained from the Samba mailing lists or from Novell.

- IBM Tivoli Directory Server can be used to provide the Samba LDAP backend. Example schema files are provided in the Samba source code tarball under the directory `~samba/example/LDAP.`

- Sun ONE Identity Server product suite provides an LDAP server that can be used for Samba. Example schema files are provided in the Samba source code tarball under the directory `~samba/example/LDAP.`

A word of caution is fully in order. OpenLDAP is purely an LDAP server, and unlike commercial offerings, it requires that you manually edit the server configuration files and manually initialize the LDAP directory database. OpenLDAP itself has only command-line tools to help you to get OpenLDAP and Samba-3 running as required, albeit with some learning curve challenges.

For most sites, the deployment of Microsoft Active Directory from the shrink-wrapped installation is quite adequate. If you are migrating from Microsoft Active Directory, be warned that OpenLDAP does not include GUI-based directory management tools. Even a simple task such as adding users to the OpenLDAP database requires an understanding of what you are doing, why you are doing it, and the tools that you must use.

When installed and configured, an OpenLDAP Identity Management backend for Samba functions well. High availability operation may be obtained through directory replication/synchronization and master/slave server configurations. OpenLDAP is a mature platform to host the organizational directory infrastructure that can include all UNIX accounts, directories for electronic mail, and much more. The price paid through learning how to design an LDAP directory schema in implementation and configuration of management tools is well rewarded by performance and flexibility and the freedom to manage directory contents with greater ability to back up, restore, and modify the directory than is generally possible with Microsoft Active Directory.

A comparison of OpenLDAP with Microsoft Active Directory does not do justice to either. OpenLDAP is an LDAP directory tool-set. Microsoft Active Directory Server is an implementation of an LDAP server that is largely preconfigured for a specific task orientation. It comes with a set of administrative tools that is entirely customized for the purpose of running MS Windows applications that include file and print services, Microsoft Exchange server, Microsoft SQL server, and more. The complexity of OpenLDAP is highly valued by the UNIX administrator who wants to build a custom directory solution. Microsoft provides an application called MS ADAM that provides more generic LDAP services, yet it does not have the vanilla-like services of OpenLDAP.

You may wish to consider outsourcing the development of your OpenLDAP directory to an expert, particularly if you find the challenge of learning about LDAP directories, schemas, configuration, and management tools and the creation of shell and Perl scripts a bit challenging. OpenLDAP can be easily customized, though it includes many ready-to-use schemas. Samba-3 provides an OpenLDAP schema file that is required for use as a passdb backend.

For those who are willing to brave the process of installing and configuring LDAP and Samba-3 interoperability, there are a few nice Web-based tools that may help you to manage your users and groups more effectively. The Web-based tools you might like to consider include the LDAP Account Manager (LAM) and the Webmin-based Webmin Idealx CGI tools.

Some additional LDAP tools should be mentioned. Every so often a Samba user reports using one of these, so it may be useful to them: GQ, a GTK-based LDAP browser; LDAP Browser/Editor ; JXplorer (by Computer Associates); and phpLDAPadmin.

### Note

The following prescriptive guidance is not an LDAP tutorial. The LDAP implementation expressly uses minimal security controls. No form of secure LDAP communications is attempted. The LDAP configuration information provided is considered to consist of the barest essentials only. You are strongly encouraged to learn more about LDAP before attempting to deploy it in a business-critical environment.

Information to help you get started with OpenLDAP is available from the OpenLDAP web site. Many people have found the book LDAP System Administration, by Jerry Carter quite useful.

Mary's problems are due to two factors. First, the absence of a domain controller on the local network is the main cause of the errors that result in blue screen crashes. Second, Mary has a large profile that must be loaded over the WAN connection. The addition of BDCs on each network segment significantly improves overall network performance for most users, but it is not enough. You must gain control over user desktops, and this must be done in a way that wins their support and does not cause further loss of staff morale. The following procedures solve this problem.

There is also an opportunity to implement smart printing features. You add this to the Samba configuration so that future printer changes can be managed without need to change desktop configurations.

You add the ability to automatically download new printer drivers, even if they are not installed in the default desktop profile. Only one example of printing configuration is given. It is assumed that you can extrapolate the principles and use them to install all printers that may be needed.

### Technical Issues

The solution provided is a minimal approach to getting OpenLDAP running as an identity management directory server for UNIX system accounts as well as for Samba. From the OpenLDAP perspective, UNIX system accounts are stored POSIX schema extensions. Samba provides its own schema to permit storage of account attributes Samba needs. Samba-3 can use the LDAP backend to store:

- Windows Networking User Accounts

- Windows NT Group Accounts

- Mapping Information between UNIX Groups and Windows NT Groups

- ID Mappings for SIDs to UIDs (also for foreign Domain SIDs)

The use of LDAP with Samba-3 makes it necessary to store UNIX accounts as well as Windows Networking accounts in the LDAP backend. This implies the need to use the PADL LDAP tools. The resolution of the UNIX group name to its GID must be enabled from either the `/etc/group` or from the LDAP backend. This requires the use of the PADL `nss_ldap` tool-set that integrates with the NSS. The same requirements exist for resolution of the UNIX username to the UID. The relationships are demonstrated in “The Interaction of LDAP, UNIX Posix Accounts and Samba Accounts”.

Figure 5.1. The Interaction of LDAP, UNIX Posix Accounts and Samba Accounts

You configure OpenLDAP so that it is operational. Before deploying the OpenLDAP, you really ought to learn how to configure secure communications over LDAP so that site security is not at risk. This is not covered in the following guidance.

When OpenLDAP has been made operative, you configure the PDC called `MASSIVE`. You initialize the Samba `secrets.tdb` file. Then you create the LDAP Interchange Format (LDIF) file from which the LDAP database can be initialized. You need to decide how best to create user and group accounts. A few hints are, of course, provided. You can also find on the enclosed CD-ROM, in the `Chap06` directory, a few tools that help to manage user and group configuration.

In order to effect folder redirection and to add robustness to the implementation, create a network default profile. All network users workstations are configured to use the new profile. Roaming profiles will automatically be deleted from the workstation when the user logs off.

The profile is configured so that users cannot change the appearance of their desktop. This is known as a mandatory profile. You make certain that users are able to use their computers efficiently.

A network logon script is used to deliver flexible but consistent network drive connections.

#### Addition of Machines to the Domain

Samba versions prior to 3.0.11 necessitated the use of a domain administrator account that maps to the UNIX UID=0. The UNIX operating system permits only the `root` user to add user and group accounts. Samba 3.0.11 introduced a new facility known as `Privileges`, which provides five new privileges that can be assigned to users and/or groups; see Table 5.1.

Table 5.1. Current Privilege Capabilities

Privilege | Description
--- | ---
SeMachineAccountPrivilege | Add machines to domain
SePrintOperatorPrivilege | Manage printers
SeAddUsersPrivilege | Add users and groups to the domain
SeRemoteShutdownPrivilege | Force shutdown from a remote system
SeDiskOperatorPrivilege | Manage disk share

In this network example use is made of one of the supported privileges purely to demonstrate how any user can now be given the ability to add machines to the domain using a normal user account that has been given the appropriate privileges.

#### Roaming Profile Background

As XP roaming profiles grow, so does the amount of time it takes to log in and out.

An XP roaming profile consists of the `HKEY_CURRENT_USER` hive file `NTUSER.DAT` and a number of folders (My Documents, Application Data, Desktop, Start Menu, Templates, NetHood, Favorites, and so on). When a user logs onto the network with the default configuration of MS Windows NT/200x/XPP, all this data is copied to the local machine under the `C:\Documents and Settings\%USERNAME%` directory. While the user is logged in, any changes made to any of these folders or to the `HKEY_CURRENT_USER` branch of the registry are made to the local copy of the profile. At logout the profile data is copied back to the server. This behavior can be changed through appropriate registry changes and/or through changes to the default user profile. In the latter case, it updates the registry with the values that are set in the profile `NTUSER.DAT` file.

The first challenge is to reduce the amount of data that must be transferred to and from the profile server as roaming profiles are processed. This includes removing all the shortcuts in the Recent directory, making sure the cache used by the Web browser is not being dumped into the `Application Data` folder, removing the Java plug-ins cache (the .jpi_cache directory in the profile), as well as training the user to not place large files on the desktop and to use his or her mapped home directory instead of the `My Documents` folder for saving documents.

Using a folder other than `My Documents` is a nuisance for some users, since many applications use it by default.

The secret to rapid loading of roaming profiles is to prevent unnecessary data from being copied back and forth, without losing any functionality. This is not difficult; it can be done by making changes to the Local Group Policy on each client as well as changing some paths in each user's `NTUSER.DAT` hive.

Every user profile has its own `NTUSER.DAT` file. This means you need to edit every user's profile, unless a better method can be followed. Fortunately, with the right preparations, this is not difficult. It is possible to remove the `NTUSER.DAT` file from each user's profile. Then just create a Network Default Profile. Of course, it is necessary to copy all files from redirected folders to the network share to which they are redirected.

#### The Local Group Policy

Without an Active Directory PDC, you cannot take full advantage of Group Policy Objects. However, you can still make changes to the Local Group Policy by using the Group Policy editor (`gpedit.msc`).

The Exclude directories in roaming profile settings can be found under User Configuration → Administrative Templates → System → User Profiles. By default this setting contains “Local Settings; Temporary Internet Files; History; Temp”.

Simply add the folders you do not wish to be copied back and forth to this semicolon-separated list. Note that this change must be made on all clients that are using roaming profiles.

#### Profile Changes

There are two changes that should be done to each user's profile. Move each of the directories that you have excluded from being copied back and forth out of the usual profile path. Modify each user's `NTUSER.DAT` file to point to the new paths that are shared over the network instead of to the default path (`C:\Documents and Settings\%USERNAME%`).

The above modifies existing user profiles. So that newly created profiles have these settings, you need to modify the `NTUSER.DAT` in the `C:\Documents and Settings\Default User` folder on each client machine, changing the same registry keys. You could do this by copying `NTUSER.DAT` to a Linux box and using `regedt32`. The basic method is described under “Configuration of Default Profile with Folder Redirection”.

#### Using a Network Default User Profile

If you are using Samba as your PDC, you should create a file share called `NETLOGON` and within that create a directory called `Default User`, which is a copy of the desired default user configuration (including a copy of `NTUSER.DAT`). If this share exists and the `Default User` folder exists, the first login from a new account pulls its configuration from it. See also the Real Men Don't Click Web site.

#### Installation of Printer Driver Auto-Download

The subject of printing is quite topical. Printing problems run second place to name resolution issues today. So far in this book, you have experienced only what is generally known as “dumb” printing. Dumb printing is the arrangement by which all drivers are manually installed on each client and the printing subsystems perform no filtering or intelligent processing. Dumb printing is easily understood. It usually works without many problems, but it has its limitations also. Dumb printing is better known as `Raw-Print-Through` printing.

Samba permits the configuration of `smart` printing using the Microsoft Windows point-and-click (also called drag-and-drop) printing. What this provides is essentially the ability to print to any printer. If the local client does not yet have a driver installed, the driver is automatically downloaded from the Samba server and installed on the client. Drag-and-drop printing is neat; it means the user never needs to fuss with driver installation, and that is a Good Thing,™ isn't it?

There is a further layer of print job processing that is known as `intelligent` printing that automatically senses the file format of data submitted for printing and then invokes a suitable print filter to convert the incoming data stream into a format suited to the printer to which the job is dispatched.

The CUPS printing subsystem is capable of intelligent printing. It has the capacity to detect the data format and apply a print filter. This means that it is feasible to install on all Windows clients a single printer driver for use with all printers that are routed through CUPS. The most sensible driver to use is one for a PostScript printer. Fortunately, Easy Software Products, the authors of CUPS, have released a PostScript printing driver for Windows. It can be installed into the Samba printing backend so that it automatically downloads to the client when needed.

This means that so long as there is a CUPS driver for the printer, all printing from Windows software can use PostScript, no matter what the actual printer language for the physical device is. It also means that the administrator can swap out a printer with a totally different type of device without ever needing to change a client workstation driver.

This book is about Samba-3, so you can confine the printing style to just the smart style of installation. Those interested in further information regarding intelligent printing should review documentation on the Easy Software Products Web site.

#### Avoiding Failures: Solving Problems Before They Happen

It has often been said that there are three types of people in the world: those who have sharp minds and those who forget things. Please do not ask what the third group is like! Well, it seems that many of us have company in the second group. There must be a good explanation why so many network administrators fail to solve apparently simple problems efficiently and effectively.

Here are some diagnostic guidelines that can be referred to when things go wrong:

##### Preliminary Advice: Dangers Can Be Avoided

The best advice regarding how to mend a broken leg is “Never break a leg!”

Newcomers to Samba and LDAP seem to struggle a great deal at first. If you want advice regarding the best way to remedy LDAP and Samba problems: “Avoid them like the plague!”

If you are now asking yourself how problems can be avoided, the best advice is to start out your learning experience with a known-good configuration. After you have seen a fully working solution, a good way to learn is to make slow and progressive changes that cause things to break, then observe carefully how and why things ceased to work.

The examples in this chapter (also in the book as a whole) are known to work. That means that they could serve as the kick-off point for your journey through fields of knowledge. Use this resource carefully; we hope it serves you well.

### Warning

Do not be lulled into thinking that you can easily adopt the examples in this book and adapt them without first working through the examples provided. A little thing overlooked can cause untold pain and may permanently tarnish your experience.

##### The Name Service Caching Daemon

The name service caching daemon (nscd) is a primary cause of difficulties with name resolution, particularly where `winbind` is used. Winbind does its own caching, thus nscd causes double caching which can lead to peculiar problems during debugging. As a rule, it is a good idea to turn off the name service caching daemon.

Operation of the name service caching daemon is controlled by the `/etc/nscd.conf` file. Typical contents of this file are as follows:

    # /etc/nscd.conf
    # An example Name Service Cache config file.  This file is needed by nscd.
    # Legal entries are:
    #       logfile                 <file>
    #       debug-level             <level>
    #       threads                 <threads to use>
    #       server-user             <user to run server as instead of root>
    #               server-user is ignored if nscd is started with -S parameters
    #       stat-user               <user who is allowed to request statistics>
    #       reload-count            unlimited|<number>
    #
    #       enable-cache            <service> <yes|no>
    #       positive-time-to-live   <service> <time in seconds>
    #       negative-time-to-live   <service> <time in seconds>
    #       suggested-size          <service> <prime number>
    #       check-files             <service> <yes|no>
    #       persistent              <service> <yes|no>
    #       shared                  <service> <yes|no>
    # Currently supported cache names (services): passwd, group, hosts
    #       logfile                 /var/log/nscd.log
    #       threads                 6
    #       server-user             nobody
    #       stat-user               somebody
            debug-level             0
    #       reload-count            5
            enable-cache            passwd          yes
            positive-time-to-live   passwd          600
            negative-time-to-live   passwd          20
            suggested-size          passwd          211
            check-files             passwd          yes
            persistent              passwd          yes
            shared                  passwd          yes
            enable-cache            group           yes
            positive-time-to-live   group           3600
            negative-time-to-live   group           60
            suggested-size          group           211
            check-files             group           yes
            persistent              group           yes
            shared                  group           yes
    # !!!!!WARNING!!!!! Host cache is insecure!!! The mechanism in nscd to
    # cache hosts will cause your local system to not be able to trust
    # forward/reverse lookup checks. DO NOT USE THIS if your system relies on
    # this sort of security mechanism. Use a caching DNS server instead.
            enable-cache            hosts           no
            positive-time-to-live   hosts           3600
            negative-time-to-live   hosts           20
            suggested-size          hosts           211
            check-files             hosts           yes
            persistent              hosts           yes
            shared                  hosts           yes

It is feasible to comment out the `passwd` and `group` entries so they will not be cached. Alternatively, it is often simpler to just disable the `nscd` service by executing (on Novell SUSE Linux):

    root#  chkconfig nscd off
    root#  rcnscd off

##### Debugging LDAP

In the example `/etc/openldap/slapd.conf` control file (see “LDAP DB_CONFIG File”) there is an entry for `loglevel 256`. To enable logging via the syslog infrastructure, it is necessary to uncomment this parameter and restart `slapd`.

LDAP log information can be directed into a file that is separate from the normal system log files by changing the `/etc/syslog.conf` file so it has the following contents:

    # Some foreign boot scripts require local7
    #
    local0,local1.*                 -/var/log/localmessages
    local2,local3.*                 -/var/log/localmessages
    local5.*                        -/var/log/localmessages
    local6,local7.*                 -/var/log/localmessages
    local4.*                        -/var/log/ldaplogs

In this case, all LDAP-related logs will be directed to the file `/var/log/ldaplogs`. This makes it easy to track LDAP errors. The snippet provides a simple example of usage that can be modified to suit local site needs. The configuration used later in this chapter reflects such customization with the intent that LDAP log files will be stored at a location that meets local site needs and wishes more fully.

##### Debugging NSS_LDAP

The basic mechanism for diagnosing problems with the nss_ldap utility involves adding to the `/etc/ldap.conf` file the following parameters:

    debug 256
    logdir /data/logs

Create the log directory as follows:

    root#  mkdir /data/logs

The diagnostic process should follow these steps:

Procedure 5.1. NSS_LDAP Diagnostic Steps

1. Verify the `nss_base_passwd, nss_base_shadow, nss_base_group` entries in the `/etc/ldap.conf` file and compare them closely with the directory tree location that was chosen when the directory was first created.

   One way this can be done is by executing:

       root#  slapcat | grep Group | grep dn
       dn: ou=Groups,dc=abmas,dc=biz
       dn: cn=Domain Admins,ou=Groups,dc=abmas,dc=biz
       dn: cn=Domain Users,ou=Groups,dc=abmas,dc=biz
       dn: cn=Domain Guests,ou=Groups,dc=abmas,dc=biz
       dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
       dn: cn=Administrators,ou=Groups,dc=abmas,dc=biz
       dn: cn=Print Operators,ou=Groups,dc=abmas,dc=biz
       dn: cn=Backup Operators,ou=Groups,dc=abmas,dc=biz
       dn: cn=Replicators,ou=Groups,dc=abmas,dc=biz

   The first line is the DIT entry point for the container for POSIX groups. The correct entry for the `/etc/ldap.conf` for the `nss_base_group` parameter therefore is the distinguished name (dn) as applied here:

       nss_base_group ou=Groups,dc=abmas,dc=biz?one

   The same process may be followed to determine the appropriate dn for user accounts. If the container for computer accounts is not the same as that for users (see the `smb.conf` file entry for `ldap machine suffix`), it may be necessary to set the following DIT dn in the `/etc/ldap.conf` file:

       nss_base_passwd dc=abmas,dc=biz?sub

   This instructs LDAP to search for machine as well as user entries from the top of the DIT down. This is inefficient, but at least should work. Note: It is possible to specify multiple `nss_base_passwd` entries in the `/etc/ldap.conf` file; they will be evaluated sequentially. Let us consider an example of use where the following DIT has been implemented:

   - User accounts are stored under the DIT: ou=Users, dc=abmas, dc=biz

   - User login accounts are under the DIT: ou=People, ou-Users, dc=abmas, dc=biz

   - Computer accounts are under the DIT: ou=Computers, ou=Users, dc=abmas, dc=biz

   The appropriate multiple entry for the `nss_base_passwd` directive in the `/etc/ldap.conf` file may be:

       nss_base_passwd ou=People,ou=Users,dc=abmas,dc=org?one
       nss_base_passwd ou=Computers,ou=Users,dc=abmas,dc=org?one

2. Perform lookups such as:

       root#  getent passwd

   Each such lookup will create an entry in the `/data/log` directory for each such process executed. The contents of each file created in this directory may provide a hint as to the cause of the a problem that is under investigation.

3. For additional diagnostic information, check the contents of the `/var/log/messages` to see what error messages are being generated as a result of the LDAP lookups. Here is an example of a successful lookup:

       slapd[12164]: conn=0 fd=10 ACCEPT from IP=127.0.0.1:33539
       (IP=0.0.0.0:389)
       slapd[12164]: conn=0 op=0 BIND dn="" method=128
       slapd[12164]: conn=0 op=0 RESULT tag=97 err=0 text=
       slapd[12164]: conn=0 op=1 SRCH base="" scope=0 deref=0
       filter="(objectClass=*)"
       slapd[12164]: conn=0 op=1 SEARCH RESULT tag=101 err=0
       nentries=1 text=
       slapd[12164]: conn=0 op=2 UNBIND
       slapd[12164]: conn=0 fd=10 closed
       slapd[12164]: conn=1 fd=10 ACCEPT from
       IP=127.0.0.1:33540 (IP=0.0.0.0:389)
       slapd[12164]: conn=1 op=0 BIND
       dn="cn=Manager,dc=abmas,dc=biz" method=128
       slapd[12164]: conn=1 op=0 BIND
       dn="cn=Manager,dc=abmas,dc=biz" mech=SIMPLE ssf=0
       slapd[12164]: conn=1 op=0 RESULT tag=97 err=0 text=
       slapd[12164]: conn=1 op=1 SRCH
       base="ou=People,dc=abmas,dc=biz" scope=1 deref=0
       filter="(objectClass=posixAccount)"
       slapd[12164]: conn=1 op=1 SRCH attr=uid userPassword
       uidNumber gidNumber cn
       homeDirectory loginShell gecos description objectClass
       slapd[12164]: conn=1 op=1 SEARCH RESULT tag=101 err=0
       nentries=2 text=
       slapd[12164]: conn=1 fd=10 closed

4. Check that the bindpw entry in the `/etc/ldap.conf` or in the `/etc/ldap.secrets` file is correct, as specified in the `/etc/openldap/slapd.conf` file.

##### Debugging Samba

The following parameters in the `smb.conf` file can be useful in tracking down Samba-related problems:

    [global]
    	...
    	log level = 5
    	log file = /var/log/samba/%m.log
    	max log size = 0
    	...

This will result in the creation of a separate log file for every client from which connections are made. The log file will be quite verbose and will grow continually. Do not forget to change these lines to the following when debugging has been completed:

    [global]
    	...
    	log level = 1
    	log file = /var/log/samba/%m.log
    	max log size = 50
    	...

The log file can be analyzed by executing:

    root#  cd /var/log/samba
    root#  grep -v "^\[200" machine_name.log

Search for hints of what may have failed by looking for the words fail and error.

##### Debugging on the Windows Client

MS Windows 2000 Professional and Windows XP Professional clients can be configured to create a netlogon.log file that can be very helpful in diagnosing network logon problems. Search the Microsoft knowledge base for detailed instructions. The techniques vary a little with each version of MS Windows.

### Political Issues

MS Windows network users are generally very sensitive to limits that may be imposed when confronted with locked-down workstation configurations. The challenge you face must be promoted as a choice between reliable, fast network operation and a constant flux of problems that result in user irritation.

### Installation Checklist

You are starting a complex project. Even though you went through the installation of a complex network in “The 500-User Office”, this network is a bigger challenge because of the large number of complex applications that must be configured before the first few steps can be validated. Take stock of what you are about to undertake, prepare yourself, and frequently review the steps ahead while making at least a mental note of what has already been completed. The following task list may help you to keep track of the task items that are covered:

- Samba-3 PDC Server Configuration

  1. DHCP and DNS servers

  2. OpenLDAP server

  3. PAM and NSS client tools

  4. Samba-3 PDC

  5. Idealx smbldap scripts

  6. LDAP initialization

  7. Create user and group accounts

  8. Printers

  9. Share point directory roots

  10. Profile directories

  11. Logon scripts

  12. Configuration of user rights and privileges

- Samba-3 BDC Server Configuration

  1. DHCP and DNS servers

  2. PAM and NSS client tools

  3. Printers

  4. Share point directory roots

  5. Profiles directories

- Windows XP Client Configuration

  1. Default profile folder redirection

  2. MS Outlook PST file relocation

  3. Delete roaming profile on logout

  4. Upload printer drivers to Samba servers

  5. Install software

  6. Creation of roll-out images

## Samba Server Implementation

The network design shown in “Network Topology 500 User Network Using ldapsam passdb backend” is not comprehensive. It is assumed that you will install additional file servers and possibly additional BDCs.

Figure 5.2. Network Topology 500 User Network Using ldapsam passdb backend

All configuration files and locations are shown for SUSE Linux 9.2 and are equally valid for SUSE Linux Enterprise Server 9. The file locations for Red Hat Linux are similar. You may need to adjust the locations for your particular Linux system distribution/implementation.

### Note

The following information applies to Samba-3.0.20 when used with the Idealx smbldap-tools scripts version 0.9.1. If using a different version of Samba or of the smbldap-tools tarball, please verify that the versions you are about to use are matching. The smbldap-tools package uses counter-entries in the LDAP directory to avoid duplication of the UIDs and GIDs that are issued for POSIX accounts. The LDAP rdn under which this information is stored are called `uidNumber` and `gidNumber` respectively. These may be located in any convenient part of the directory information tree (DIT). In the examples that follow they have been located under `dn=sambaDomainName=MEGANET2,dc=abmas,dc=org`. They could just as well be located under the rdn `cn=NextFreeUnixId`.

The steps in the process involve changes from the network configuration shown in “The 500-User Office”. Before implementing the following steps, you must have completed the network implementation shown in that chapter. If you are starting with newly installed Linux servers, you must complete the steps shown in “Installation of DHCP, DNS, and Samba Control Files” before commencing at “OpenLDAP Server Configuration”.

### OpenLDAP Server Configuration

Confirm that the packages shown in “Required OpenLDAP Linux Packages” are installed on your system.

Table 5.2. Required OpenLDAP Linux Packages

SUSE Linux 8.x | SUSE Linux 9.x | Red Hat Linux
--- | --- | ---
nss_ldap | nss_ldap | nss_ldap
pam_ldap | pam_ldap | pam_ldap
openldap2 | openldap2 | openldap
openldap2-client | openldap2-client |

Samba-3 and OpenLDAP will have a degree of interdependence that is unavoidable. The method for bootstrapping the LDAP and Samba-3 configuration is relatively straightforward. If you follow these guidelines, the resulting system should work fine.

Procedure 5.2. OpenLDAP Server Configuration Steps

1. Install the file shown in “LDAP Master Configuration File /etc/openldap/slapd.conf Part A” in the directory `/etc/openldap`.

2. Remove all files from the directory `/data/ldap`, making certain that the directory exists with permissions:

       root#  ls -al /data | grep ldap
       drwx------   2 ldap    ldap       48 Dec 15 22:11 ldap

   This may require you to add a user and a group account for LDAP if they do not exist.

3. Install the file shown in “LDAP DB_CONFIG File” in the directory `/data/ldap`. In the event that this file is added after `ldap` has been started, it is possible to cause the new settings to take effect by shutting down the `LDAP` server, executing the `db_recover` command inside the `/data/ldap` directory, and then restarting the `LDAP` server.

4. Performance logging can be enabled and should preferably be sent to a file on a file system that is large enough to handle significantly sized logs. To enable the logging at a verbose level to permit detailed analysis, uncomment the entry in the `/etc/openldap/slapd.conf` shown as “loglevel 256”.

   Edit the `/etc/syslog.conf` file to add the following at the end of the file:

       local4.*        -/data/ldap/log/openldap.log

   Note: The path `/data/ldap/log` should be set at a location that is convenient and that can store a large volume of data.

Example 5.1. LDAP DB_CONFIG File

    set_cachesize           0 150000000 1
    set_lg_regionmax        262144
    set_lg_bsize            2097152
    #set_lg_dir             /var/log/bdb
    set_flags               DB_LOG_AUTOREMOVE

Example 5.2. LDAP Master Configuration File `/etc/openldap/slapd.conf` Part A

    include		/etc/openldap/schema/core.schema
    include		/etc/openldap/schema/cosine.schema
    include		/etc/openldap/schema/inetorgperson.schema
    include		/etc/openldap/schema/nis.schema
    include		/etc/openldap/schema/samba3.schema

    pidfile		/var/run/slapd/slapd.pid
    argsfile	/var/run/slapd/slapd.args

    access to dn.base=""
    		by self write
    		by * auth

    access to attr=userPassword
    		by self write
    		by * auth

    access to attr=shadowLastChange
    		by self write
    		by * read

    access to *
                    by * read
                    by anonymous auth

    #loglevel	256

    schemacheck 	on
    idletimeout	30
    backend		bdb
    database	bdb
    checkpoint      1024 5
    cachesize       10000

    suffix		"dc=abmas,dc=biz"
    rootdn		"cn=Manager,dc=abmas,dc=biz"

    # rootpw = not24get
    rootpw          {SSHA}86kTavd9Dw3FAz6qzWTrCOKX/c0Qe+UV

    directory	/data/ldap

Example 5.3. LDAP Master Configuration File `/etc/openldap/slapd.conf` Part B

    # Indices to maintain
    index objectClass           eq
    index cn                    pres,sub,eq
    index sn                    pres,sub,eq
    index uid                   pres,sub,eq
    index displayName           pres,sub,eq
    index uidNumber             eq
    index gidNumber             eq
    index memberUID             eq
    index sambaSID              eq
    index sambaPrimaryGroupSID  eq
    index sambaDomainName       eq
    index default               sub

### PAM and NSS Client Configuration

The steps that follow involve configuration of LDAP, NSS LDAP-based resolution of users and groups. Also, so that LDAP-based accounts can log onto the system, the steps ahead configure the Pluggable Authentication Modules (PAM) to permit LDAP-based authentication.

Since you have chosen to put UNIX user and group accounts into the LDAP database, it is likely that you may want to use them for UNIX system (Linux) local machine logons. This necessitates correct configuration of PAM. The `pam_ldap` open source package provides the PAM modules that most people would use. On SUSE Linux systems, the `pam_unix2.so` module also has the ability to redirect authentication requests through LDAP.

You have chosen to configure these services by directly editing the system files, but of course, you know that this configuration can be done using system tools provided by the Linux system vendor. SUSE Linux has a facility in YaST (the system admin tool) through yast → system → ldap-client that permits configuration of SUSE Linux as an LDAP client. Red Hat Linux provides the `authconfig` tool for this.

Procedure 5.3. PAM and NSS Client Configuration Steps

Example 5.4. Configuration File for NSS LDAP Support `/etc/ldap.conf`

    host 127.0.0.1

    base dc=abmas,dc=biz

    binddn cn=Manager,dc=abmas,dc=biz
    bindpw not24get

    timelimit 50
    bind_timelimit 50
    bind_policy hard

    idle_timelimit 3600

    pam_password exop

    nss_base_passwd ou=People,dc=abmas,dc=biz?one
    nss_base_shadow ou=People,dc=abmas,dc=biz?one
    nss_base_group  ou=Groups,dc=abmas,dc=biz?one

    ssl off

Example 5.5. Configuration File for NSS LDAP Clients Support `/etc/ldap.conf`

    host 172.16.0.1

    base dc=abmas,dc=biz

    binddn cn=Manager,dc=abmas,dc=biz
    bindpw not24get

    timelimit 50
    bind_timelimit 50
    bind_policy hard

    idle_timelimit 3600

    pam_password exop

    nss_base_passwd ou=People,dc=abmas,dc=biz?one
    nss_base_shadow ou=People,dc=abmas,dc=biz?one
    nss_base_group  ou=Groups,dc=abmas,dc=biz?one

    ssl off

1. Execute the following command to find where the `nss_ldap` module expects to find its control file:

       root#  strings /lib/libnss_ldap.so.2 | grep conf

   The preferred and usual location is `/etc/ldap.conf`.

2. On the server `MASSIVE`, install the file shown in “Configuration File for NSS LDAP Support /etc/ldap.conf” into the path that was obtained from the step above. On the servers called `BLDG1` and `BLDG2`, install the file shown in “Configuration File for NSS LDAP Clients Support /etc/ldap.conf” into the path that was obtained from the step above.

3. Edit the NSS control file (`/etc/nsswitch.conf`) so that the lines that control user and group resolution will obtain information from the normal system files as well as from `ldap`:

       passwd: files ldap
       shadow: files ldap
       group:  files ldap
       hosts:  files dns wins

   Later, when the LDAP database has been initialized and user and group accounts have been added, you can validate resolution of the LDAP resolver process. The inclusion of WINS-based hostname resolution is deliberate so that all MS Windows client hostnames can be resolved to their IP addresses, whether or not they are DHCP clients.

   ### Note

   Some Linux systems (Novell SUSE Linux in particular) add entries to the `nsswitch.conf` file that may cause operational problems with the configuration methods adopted in this book. It is advisable to comment out the entries `passwd_compat` and `group_compat` where they are found in this file.

   Even at the risk of overstating the issue, incorrect and inappropriate configuration of the `nsswitch.conf` file is a significant cause of operational problems with LDAP.

4. For PAM LDAP configuration on this SUSE Linux 9.0 system, the simplest solution is to edit the following files in the `/etc/pam.d` directory: `login`, `password`, `samba`, `sshd`. In each file, locate every entry that has the `pam_unix2.so` entry and add to the line the entry `use_ldap` as shown for the `login` module in this example:

       #%PAM-1.0
       auth      requisite  pam_unix2.so   nullok use_ldap #set_secrpc
       auth      required   pam_securetty.so
       auth      required   pam_nologin.so
       #auth     required   pam_homecheck.so
       auth      required   pam_env.so
       auth      required   pam_mail.so
       account   required   pam_unix2.so   use_ldap
       password  required   pam_pwcheck.s  nullok
       password  required   pam_unix2.so   nullok use_first_pass \
                                           use_authtok use_ldap
       session   required   pam_unix2.so   none use_ldap # debug or trace
       session   required   pam_limits.so

   On other Linux systems that do not have an LDAP-enabled `pam_unix2.so` module, you must edit these files by adding the `pam_ldap.so` modules as shown here:

       #%PAM-1.0
       auth     required    pam_securetty.so
       auth     required    pam_nologin.so
       auth     sufficient  pam_ldap.so
       auth     required    pam_unix2.so   nullok try_first_pass #set_secrpc
       account  sufficient  pam_ldap.so
       account  required    pam_unix2.so
       password required    pam_pwcheck.so nullok
       password required    pam_ldap.so    use_first_pass use_authtok
       password required    pam_unix2.so   nullok use_first_pass use_authtok
       session  required    pam_unix2.so   none # debug or trace
       session  required    pam_limits.so
       session  required    pam_env.so
       session  optional    pam_mail.so

   This example does have the LDAP-enabled `pam_unix2.so`, but simply demonstrates the use of the `pam_ldap.so` module. You can use either implementation, but if the `pam_unix2.so` on your system supports LDAP, you probably want to use it rather than add an additional module.

### Samba-3 PDC Configuration

Verify that the Samba-3.0.20 (or later) packages are installed on each SUSE Linux server before following the steps below. If Samba-3.0.20 (or later) is not installed, you have the choice to either build your own or obtain the packages from a dependable source. Packages for SUSE Linux 8.x, 9.x, and SUSE Linux Enterprise Server 9, as well as for Red Hat Fedora Core and Red Hat Enterprise Linux Server 3 and 4, are included on the CD-ROM that is included with this book.

Procedure 5.4. Configuration of PDC Called `MASSIVE`

1. Install the files in “LDAP Based smb.conf File, Server: MASSIVE global Section: Part A”, “LDAP Based smb.conf File, Server: MASSIVE global Section: Part B”, “LDAP Based smb.conf File, Shares Section Part A”, and “LDAP Based smb.conf File, Shares Section Part B” into the `/etc/samba/` directory. The three files should be added together to form the `smb.conf` master file. It is a good practice to call this file something like `smb.conf.master` and then to perform all file edits on the master file. The operational `smb.conf` is then generated as shown in the next step.

2. Create and verify the contents of the `smb.conf` file that is generated by:

       root#  testparm -s smb.conf.master > smb.conf

   Immediately follow this with the following:

       root#  testparm

   The output that is created should be free from errors, as shown here:

       Load smb config files from /etc/samba/smb.conf
       Processing section "[accounts]"
       Processing section "[service]"
       Processing section "[pidata]"
       Processing section "[homes]"
       Processing section "[printers]"
       Processing section "[apps]"
       Processing section "[netlogon]"
       Processing section "[profiles]"
       Processing section "[profdata]"
       Processing section "[print$]"
       Loaded services file OK.
       Server role: ROLE_DOMAIN_PDC
       Press enter to see a dump of your service definitions

3. Delete all runtime files from prior Samba operation by executing (for SUSE Linux):

       root#  rm /etc/samba/*tdb
       root#  rm /var/lib/samba/*tdb
       root#  rm /var/lib/samba/*dat
       root#  rm /var/log/samba/*

4. Samba-3 communicates with the LDAP server. The password that it uses to authenticate to the LDAP server must be stored in the `secrets.tdb` file. Execute the following to create the new `secrets.tdb` files and store the password for the LDAP Manager:

       root#  smbpasswd -w not24get

   The expected output from this command is:

       Setting stored password for "cn=Manager,dc=abmas,dc=biz" in secrets.tdb

5. Samba-3 generates a Windows Security Identifier (SID) only when `smbd` has been started. For this reason, you start Samba. After a few seconds delay, execute:

       root#  smbclient -L localhost -U%
       root#  net getlocalsid

   A report such as the following means that the domain SID has not yet been written to the `secrets.tdb` or to the LDAP backend:

       [2005/03/03 23:19:34, 0] lib/smbldap.c:smbldap_connect_system(852)
         failed to bind to server ldap://massive.abmas.biz
       with dn="cn=Manager,dc=abmas,dc=biz" Error: Can't contact LDAP server
               (unknown)
       [2005/03/03 23:19:48, 0] lib/smbldap.c:smbldap_search_suffix(1169)
         smbldap_search_suffix: Problem during the LDAP search:
               (unknown) (Timed out)

   The attempt to read the SID will cause and attempted bind to the LDAP server. Because the LDAP server is not running, this operation will fail by way of a timeout, as shown previously. This is normal output; do not worry about this error message. When the domain has been created and written to the `secrets.tdb` file, the output should look like this:

       SID for domain MASSIVE is: S-1-5-21-3504140859-1010554828-2431957765

   If, after a short delay (a few seconds), the domain SID has still not been written to the `secrets.tdb` file, it is necessary to investigate what may be misconfigured. In this case, carefully check the `smb.conf` file for typographical errors (the most common problem). The use of the `testparm` is highly recommended to validate the contents of this file.

6. When a positive domain SID has been reported, stop Samba.

7. Configure the NFS server for your Linux system. So you can complete the steps that follow, enter into the `/etc/exports` the following entry:

       /home   *(rw,root_squash,sync)

   This permits the user home directories to be used on the BDC servers for testing purposes. You, of course, decide what is the best way for your site to distribute data drives, and you create suitable backup and restore procedures for Abmas I'd strongly recommend that for normal operation the BDC is completely independent of the PDC. rsync is a useful tool here, as it resembles the NT replication service quite closely. If you do use NFS, do not forget to start the NFS server as follows:

       root#  rcnfsserver start

Your Samba-3 PDC is now ready to communicate with the LDAP password backend. Let's get on with configuration of the LDAP server.

Example 5.6. LDAP Based `smb.conf` File, Server: MASSIVE global Section: Part A

# Global parameters
`[global]`
`unix charset = LOCALE`
`workgroup = MEGANET2`
`netbios name = MASSIVE`
`interfaces = eth1, lo`
`bind interfaces only = Yes`
`passdb backend = ldapsam:ldap://massive.abmas.biz`
`enable privileges = Yes`
`username map = /etc/samba/smbusers`
`log level = 1`
`syslog = 0`
`log file = /var/log/samba/%m`
`max log size = 50`
`smb ports = 139`
`name resolve order = wins bcast hosts`
`time server = Yes`
`printcap name = CUPS`
`show add printer wizard = No`
`add user script = /opt/IDEALX/sbin/smbldap-useradd -m "%u"`
`delete user script = /opt/IDEALX/sbin/smbldap-userdel "%u"`
`add group script = /opt/IDEALX/sbin/smbldap-groupadd -p "%g"`
`delete group script = /opt/IDEALX/sbin/smbldap-groupdel "%g"`
`add user to group script = /opt/IDEALX/sbin/smbldap-groupmod -m "%u" "%g"`
`delete user from group script = /opt/IDEALX/sbin/smbldap-groupmod -x "%u" "%g"`
`set primary group script = /opt/IDEALX/sbin/smbldap-usermod -g "%g" "%u"`
`add machine script = /opt/IDEALX/sbin/smbldap-useradd -w "%u"`

Example 5.7. LDAP Based `smb.conf` File, Server: MASSIVE global Section: Part B

`logon script = scripts\logon.bat`
`logon path = \\%L\profiles\%U`
`logon drive = X:`
`domain logons = Yes`
`preferred master = Yes`
`wins support = Yes`
`ldap suffix = dc=abmas,dc=biz`
`ldap machine suffix = ou=People`
`ldap user suffix = ou=People`
`ldap group suffix = ou=Groups`
`ldap idmap suffix = ou=Idmap`
`ldap admin dn = cn=Manager,dc=abmas,dc=biz`
`idmap backend = ldap:ldap://massive.abmas.biz`
`idmap uid = 10000-20000`
`idmap gid = 10000-20000`
`map acl inherit = Yes`
`printing = cups`
`printer admin = root, chrisr`

### Install and Configure Idealx smbldap-tools Scripts

The Idealx scripts, or equivalent, are necessary to permit Samba-3 to manage accounts on the LDAP server. You have chosen the Idealx scripts because they are the best-known LDAP configuration scripts. The use of these scripts will help avoid the necessity to create custom scripts. It is easy to download them from the Idealx Web site. The tarball may be directly downloaded from this site also. Alternatively, you may obtain the smbldap-tools-0.9.1-1.src.rpm file that may be used to build an installable RPM package for your Linux system.

### Note

The smbldap-tools scripts can be installed in any convenient directory of your choice, in which case you must change the path to them in your `smb.conf` file on the PDC (`MASSIVE`).

The smbldap-tools are located in `/opt/IDEALX/sbin`. The scripts are not needed on BDC machines because all LDAP updates are handled by the PDC alone.

#### Installation of smbldap-tools from the Tarball

To perform a manual installation of the smbldap-tools scripts, the following procedure may be used:

Procedure 5.5. Unpacking and Installation Steps for the `smbldap-tools` Tarball

1. Create the `/opt/IDEALX/sbin` directory, and set its permissions and ownership as shown here:

       root#  mkdir -p /opt/IDEALX/sbin
       root#  chown root:root /opt/IDEALX/sbin
       root#  chmod 755 /opt/IDEALX/sbin
       root#  mkdir -p /etc/smbldap-tools
       root#  chown root:root /etc/smbldap-tools
       root#  chmod 755 /etc/smbldap-tools

2. If you wish to use the downloaded tarball, unpack the smbldap-tools in a suitable temporary location. Change into either the directory extracted from the tarball or the smbldap-tools directory in your `/usr/share/doc/packages` directory tree.

3. Copy all the `smbldap-*` and the `configure.pl` files into the `/opt/IDEALX/sbin` directory, as shown here:

       root#  cd smbldap-tools-0.9.1/
       root#  cp smbldap-* configure.pl *pm /opt/IDEALX/sbin/
       root#  cp smbldap*conf /etc/smbldap-tools/
       root#  chmod 750 /opt/IDEALX/sbin/smbldap-*
       root#  chmod 750 /opt/IDEALX/sbin/configure.pl
       root#  chmod 640 /etc/smbldap-tools/smbldap.conf
       root#  chmod 600 /etc/smbldap-tools/smbldap_bind.conf

4. The smbldap-tools scripts master control file must now be configured. Change to the `/opt/IDEALX/sbin` directory, then edit the `smbldap_tools.pm` to affect the changes shown here:

       ...
       # ugly funcs using global variables and spawning openldap clients

       my $smbldap_conf="/etc/smbldap-tools/smbldap.conf";
       my $smbldap_bind_conf="/etc/smbldap-tools/smbldap_bind.conf";
       ...

5. To complete the configuration of the smbldap-tools, set the permissions and ownership by executing the following commands:

       root#  chown root:root /opt/IDEALX/sbin/*
       root#  chmod 755 /opt/IDEALX/sbin/smbldap-*
       root#  chmod 640 /opt/IDEALX/sbin/smb*pm

   The smbldap-tools scripts are now ready for the configuration step outlined in “Configuration of smbldap-tools”.

#### Installing smbldap-tools from the RPM Package

In the event that you have elected to use the RPM package provided by Idealx, download the source RPM `smbldap-tools-0.9.1-1.src.rpm`, then follow this procedure:

Procedure 5.6. Installation Steps for `smbldap-tools` RPM's

1. Install the source RPM that has been downloaded as follows:

       root#  rpm -i smbldap-tools-0.9.1-1.src.rpm

2. Change into the directory in which the SPEC files are located. On SUSE Linux:

       root#  cd /usr/src/packages/SPECS

   On Red Hat Linux systems:

       root#  cd /usr/src/redhat/SPECS

3. Edit the `smbldap-tools.spec` file to change the value of the `_sysconfig` macro as shown here:

       %define _prefix /opt/IDEALX
       %define _sysconfdir /etc

   Note: Any suitable directory can be specified.

4. Build the package by executing:

       root#  rpmbuild -ba -v smbldap-tools.spec

   A build process that has completed without error will place the installable binary files in the directory `../RPMS/noarch`.

5. Install the binary package by executing:

       root#  rpm -Uvh ../RPMS/noarch/smbldap-tools-0.9.1-1.noarch.rpm

The Idealx scripts should now be ready for configuration using the steps outlined in Configuration of smbldap-tools.

#### Configuration of smbldap-tools

Prior to use, the smbldap-tools must be configured to match the settings in the `smb.conf` file and to match the settings in the `/etc/openldap/slapd.conf` file. The assumption is made that the `smb.conf` file has correct contents. The following procedure ensures that this is completed correctly:

The smbldap-tools require that the NetBIOS name (machine name) of the Samba server be included in the `smb.conf` file.

Procedure 5.7. Configuration Steps for `smbldap-tools` to Enable Use

1. Change into the directory that contains the `configure.pl` script.

       root#  cd /opt/IDEALX/sbin

2. Execute the `configure.pl` script as follows:

       root#  ./configure.pl

   The interactive use of this script for the PDC is demonstrated here:

       root#  /opt/IDEALX/sbin/configure.pl
       -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
              smbldap-tools script configuration
              -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
       Before starting, check
        . if your samba controller is up and running.
        . if the domain SID is defined (you can get it with the
                                                           'net getlocalsid')

        . you can leave the configuration using the Crtl-c key combination
        . empty value can be set with the "." character
       -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
       Looking for configuration files...

       Samba Config File Location [/etc/samba/smb.conf] >
       smbldap-tools configuration file Location (global parameters)
                               [/etc/opt/IDEALX/smbldap-tools/smbldap.conf] >
       smbldap Config file Location (bind parameters)
                          [/etc/opt/IDEALX/smbldap-tools/smbldap_bind.conf] >
       -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
       Let's start configuring the smbldap-tools scripts ...

       . workgroup name: name of the domain Samba act as a PDC
         workgroup name [MEGANET2] >
       . netbios name: netbios name of the samba controler
         netbios name [MASSIVE] >
       . logon drive: local path to which the home directory
                           will be connected (for NT Workstations). Ex: 'H:'
         logon drive [H:] >
       . logon home: home directory location (for Win95/98 or NT Workstation)
         (use %U as username) Ex:'\\MASSIVE\%U'
         logon home (press the "." character if you don't want homeDirectory)
                                                            [\\MASSIVE\%U] >
       . logon path: directory where roaming profiles are stored.
                                                   Ex:'\\MASSIVE\profiles\%U'
         logon path (press the "." character
                      if you don't want roaming profile) [\\%L\profiles\%U] >
       . home directory prefix (use %U as username)
                                                  [/home/%U] > /data/users/%U
       . default users' homeDirectory mode [700] >
       . default user netlogon script (use %U as username)
                                                        [scripts\logon.bat] >
         default password validation time (time in days) [45] > 900
       . ldap suffix [dc=abmas,dc=biz] >
       . ldap group suffix [ou=Groups] >
       . ldap user suffix [ou=People,ou=Users] >
       . ldap machine suffix [ou=Computers,ou=Users] >
       . Idmap suffix [ou=Idmap] >
       . sambaUnixIdPooldn: object where you want to store the next uidNumber
         and gidNumber available for new users and groups
         sambaUnixIdPooldn object (relative to ${suffix})
                                                 [sambaDomainName=MEGANET2] >
       . ldap master server: IP adress or DNS name of the master
                                                       (writable) ldap server
         ldap master server [massive.abmas.biz] >
       . ldap master port [389] >
       . ldap master bind dn [cn=Manager,dc=abmas,dc=biz] >
       . ldap master bind password [] >
       . ldap slave server: IP adress or DNS name of the slave ldap server:
                                                   can also be the master one
         ldap slave server [massive.abmas.biz] >
       . ldap slave port [389] >
       . ldap slave bind dn [cn=Manager,dc=abmas,dc=biz] >
       . ldap slave bind password [] >
       . ldap tls support (1/0) [0] >
       . SID for domain MEGANET2: SID of the domain
                             (can be obtained with 'net getlocalsid MASSIVE')
         SID for domain MEGANET2
                               [S-1-5-21-3504140859-1010554828-2431957765]] >
       . unix password encryption: encryption used for unix passwords
         unix password encryption (CRYPT, MD5, SMD5, SSHA, SHA) [SSHA] > MD5
       . default user gidNumber [513] >
       . default computer gidNumber [515] >
       . default login shell [/bin/bash] >
       . default skeleton directory [/etc/skel] >
       . default domain name to append to mail adress [] > abmas.biz
       -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
       backup old configuration files:
         /etc/opt/IDEALX/smbldap-tools/smbldap.conf->
                               /etc/opt/IDEALX/smbldap-tools/smbldap.conf.old
         /etc/opt/IDEALX/smbldap-tools/smbldap_bind.conf->
                          /etc/opt/IDEALX/smbldap-tools/smbldap_bind.conf.old
       writing new configuration file:
         /etc/opt/IDEALX/smbldap-tools/smbldap.conf done.
         /etc/opt/IDEALX/smbldap-tools/smbldap_bind.conf done.

   Since a slave LDAP server has not been configured, it is necessary to specify the IP address of the master LDAP server for both the master and the slave configuration prompts.

3. Change to the directory that contains the `smbldap.conf` file, then verify its contents.

The smbldap-tools are now ready for use.

### LDAP Initialization and Creation of User and Group Accounts

The LDAP database must be populated with well-known Windows domain user accounts and domain group accounts before Samba can be used. The following procedures step you through the process.

At this time, Samba-3 requires that on a PDC all UNIX (POSIX) group accounts that are mapped (linked) to Windows domain group accounts must be in the LDAP database. It does not hurt to have UNIX user and group accounts in both the system files as well as in the LDAP database. From a UNIX system perspective, the NSS resolver checks system files before referring to LDAP. If the UNIX system can resolve (find) an account in the system file, it does not need to ask LDAP.

Addition of an account to the LDAP backend can be done in two ways:

- If you always have a user account in the `/etc/passwd` on every server or in a NIS(+) backend, it is not necessary to add POSIX accounts for them in LDAP. In this case, you can add Windows domain user accounts using the `pdbedit` utility. Use of this tool from the command line adds the SambaSamAccount entry for the user, but does not add the PosixAccount entry for the user.

  This is the least desirable method because when LDAP is used as the passwd backend Samba expects the POSIX account to be in LDAP also. It is possible to use the PADL account migration tool to migrate all system accounts from either the `/etc/passwd` files, or from NIS, to LDAP.

- If you decide that it is probably a good idea to add both the PosixAccount attributes as well as the SambaSamAccount attributes for each user, then a suitable script is needed. In the example system you are installing in this exercise, you are making use of the Idealx smbldap-tools scripts. A copy of these tools, preconfigured for this system, is included on the enclosed CD-ROM under `Chap06/Tools.`

If you wish to have more control over how the LDAP database is initialized or if you don't want to use the Idealx smbldap-tools, you should refer to “A Collection of Useful Tidbits”, “Alternative LDAP Database Initialization”.

The following steps initialize the LDAP database, and then you can add user and group accounts that Samba can use. You use the `smbldap-populate` to seed the LDAP database. You then manually add the accounts shown in “Abmas Network Users and Groups”. The list of users does not cover all 500 network users; it provides examples only.

### Note

In the following examples, as the LDAP database is initialized, we do create a container for Computer (machine) accounts. In the Samba-3 `smb.conf` files, specific use is made of the People container, not the Computers container, for domain member accounts. This is not a mistake; it is a deliberate action that is necessitated by the fact that the resolution of a machine (computer) account to a UID is done via NSS. The only way this can be handled is using the NSS (`/etc/nsswitch.conf`) entry for `passwd`, which is resolved using the `nss_ldap` library. The configuration file for the `nss_ldap` library is the file `/etc/ldap.conf` that provides only one possible LDAP search command that is specified by the entry called `nss_base_passwd`. This means that the search path must take into account the directory structure so that the LDAP search will commence at a level that is above both the Computers container and the Users (or People) container. If this is done, it is necessary to use a search that will descend the directory tree so that the machine account can be found. Alternatively, by placing all machine accounts in the People container, we are able to sidestep this limitation. This is the simpler solution that has been adopted in this chapter.

Table 5.3. Abmas Network Users and Groups

Account Name | Type | ID | Password
--- | --- | --- | ---
Robert Jordan | User | bobj | n3v3r2l8
Stanley Soroka | User | stans | impl13dst4r
Christine Roberson | User | chrisr | S9n0nw4ll
Mary Vortexis | User | maryv | kw13t0n3
Accounts | Group | Accounts |
Finances | Group | Finances |
Insurance | Group | PIOps |

Procedure 5.8. LDAP Directory Initialization Steps

1. Start the LDAP server by executing:

       root#  rcldap start
       Starting ldap-server                           done

2. Change to the `/opt/IDEALX/sbin` directory.

3. Execute the script that will populate the LDAP database as shown here:

       root#  ./smbldap-populate -a root -k 0 -m 0

   The expected output from this is:

       Using workgroup name from smb.conf: sambaDomainName=MEGANET2
       -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
       => Warning: you must update smbldap.conf configuration file to :
       => sambaUnixIdPooldn parameter must be set
       	to "sambaDomainName=MEGANET2,dc=abmas,dc=biz"
       -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
       Using builtin directory structure
       adding new entry: dc=abmas,dc=biz
       adding new entry: ou=People,dc=abmas,dc=biz
       adding new entry: ou=Groups,dc=abmas,dc=biz
       entry ou=People,dc=abmas,dc=biz already exist.
       adding new entry: ou=Idmap,dc=abmas,dc=biz
       adding new entry: sambaDomainName=MEGANET2,dc=abmas,dc=biz
       adding new entry: uid=root,ou=People,dc=abmas,dc=biz
       adding new entry: uid=nobody,ou=People,dc=abmas,dc=biz
       adding new entry: cn=Domain Admins,ou=Groups,dc=abmas,dc=biz
       adding new entry: cn=Domain Users,ou=Groups,dc=abmas,dc=biz
       adding new entry: cn=Domain Guests,ou=Groups,dc=abmas,dc=biz
       adding new entry: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
       adding new entry: cn=Administrators,ou=Groups,dc=abmas,dc=biz
       adding new entry: cn=Print Operators,ou=Groups,dc=abmas,dc=biz
       adding new entry: cn=Backup Operators,ou=Groups,dc=abmas,dc=biz
       adding new entry: cn=Replicators,ou=Groups,dc=abmas,dc=biz

4. Edit the `/etc/smbldap-tools/smbldap.conf` file so that the following information is changed from:

       # Where to store next uidNumber and gidNumber available
       sambaUnixIdPooldn="cn=NextFreeUnixId,${suffix}"

   to read, after modification:

       # Where to store next uidNumber and gidNumber available
       #sambaUnixIdPooldn="cn=NextFreeUnixId,${suffix}"
       sambaUnixIdPooldn="sambaDomainName=MEGANET2,dc=abmas,dc=biz"

5. It is necessary to restart the LDAP server as shown here:

       root#  rcldap restart
       Shutting down ldap-server                            done
       Starting ldap-server                                 done

6. So that we can use a global IDMAP repository, the LDAP directory must have a container object for IDMAP data. There are several ways you can check that your LDAP database is able to receive IDMAP information. One of the simplest is to execute:

       root#  slapcat | grep -i idmap
       dn: ou=Idmap,dc=abmas,dc=biz
       ou: idmap

   If the execution of this command does not return IDMAP entries, you need to create an LDIF template file (see “LDIF IDMAP Add-On Load File File: /etc/openldap/idmap.LDIF”). You can add the required entries using the following command:

       root#  ldapadd -x -D "cn=Manager,dc=abmas,dc=biz" \
       		-w not24get < /etc/openldap/idmap.LDIF

   Samba automatically populates this LDAP directory container when it needs to.

7. It looks like all has gone well, as expected. Let's confirm that this is the case by running a few tests. First we check the contents of the database directly by running `slapcat` as follows (the output has been cut down):

       root#  slapcat
       dn: dc=abmas,dc=biz
       objectClass: dcObject
       objectClass: organization
       dc: abmas
       o: abmas
       structuralObjectClass: organization
       entryUUID: 5ab02bf6-c536-1027-9d29-b1f32350fb43
       creatorsName: cn=Manager,dc=abmas,dc=biz
       createTimestamp: 20031217234200Z
       entryCSN: 2003121723:42:00Z#0x0001#0#0000
       modifiersName: cn=Manager,dc=abmas,dc=biz
       modifyTimestamp: 20031217234200Z
       ...
       dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
       objectClass: posixGroup
       objectClass: sambaGroupMapping
       gidNumber: 553
       cn: Domain Computers
       description: Netbios Domain Computers accounts
       sambaSID: S-1-5-21-3504140859-1010554828-2431957765-553
       sambaGroupType: 2
       displayName: Domain Computers
       structuralObjectClass: posixGroup
       entryUUID: 5e0a41d8-c536-1027-9d3b-b1f32350fb43
       creatorsName: cn=Manager,dc=abmas,dc=biz
       createTimestamp: 20031217234206Z
       entryCSN: 2003121723:42:06Z#0x0002#0#0000
       modifiersName: cn=Manager,dc=abmas,dc=biz
       modifyTimestamp: 20031217234206Z

   This looks good so far.

8. The next step is to prove that the LDAP server is running and responds to a search request. Execute the following as shown (output has been cut to save space):

       root#  ldapsearch -x -b "dc=abmas,dc=biz" "(ObjectClass=*)"
       # extended LDIF
       #
       # LDAPv3
       # base <dc=abmas,dc=biz> with scope sub
       # filter: (ObjectClass=*)
       # requesting: ALL
       #

       # abmas.biz
       dn: dc=abmas,dc=biz
       objectClass: dcObject
       objectClass: organization
       dc: abmas
       o: abmas

       # People, abmas.biz
       dn: ou=People,dc=abmas,dc=biz
       objectClass: organizationalUnit
       ou: People
       ...
       # Domain Computers, Groups, abmas.biz
       dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
       objectClass: posixGroup
       objectClass: sambaGroupMapping
       gidNumber: 553
       cn: Domain Computers
       description: Netbios Domain Computers accounts
       sambaSID: S-1-5-21-3504140859-1010554828-2431957765-553
       sambaGroupType: 2
       displayName: Domain Computers

       # search result
       search: 2
       result: 0 Success

       # numResponses: 20
       # numEntries: 19

   Good. It is all working just fine.

9. You must now make certain that the NSS resolver can interrogate LDAP also. Execute the following commands:

       root#  getent passwd | grep root
       root:x:998:512:Netbios Domain Administrator:/home:/bin/false

       root#  getent group | grep Domain
       Domain Admins:x:512:root
       Domain Users:x:513:
       Domain Guests:x:514:
       Domain Computers:x:553:

   This demonstrates that the `nss_ldap` library is functioning as it should. If these two steps fail to produce this information, refer to “Avoiding Failures: Solving Problems Before They Happen” for diagnostic procedures that can be followed to isolate the cause of the problem. Proceed to the next step only when the previous steps have been successfully completed.

10. Our database is now ready for the addition of network users. For each user for whom an account must be created, execute the following:

        root#  ./smbldap-useradd -m -a username
        root#  ./smbldap-passwd username
        Changing password for username
        New password : XXXXXXXX
        Retype new password : XXXXXXXX

        root#  smbpasswd username
        New SMB password: XXXXXXXX
        Retype new SMB password: XXXXXXXX

    where `username` is the login ID for each user.

11. Now verify that the UNIX (POSIX) accounts can be resolved via NSS by executing the following:

        root#  getent passwd
        root:x:0:0:root:/root:/bin/bash
        bin:x:1:1:bin:/bin:/bin/bash
        ...
        root:x:0:512:Netbios Domain Administrator:/home:/bin/false
        nobody:x:999:514:nobody:/dev/null:/bin/false
        bobj:x:1000:513:System User:/home/bobj:/bin/bash
        stans:x:1001:513:System User:/home/stans:/bin/bash
        chrisr:x:1002:513:System User:/home/chrisr:/bin/bash
        maryv:x:1003:513:System User:/home/maryv:/bin/bash

    This demonstrates that user account resolution via LDAP is working.

12. This step will determine whether or not identity resolution is working correctly. Do not procede is this step fails, rather find the cause of the failure. The `id` command may be used to validate your configuration so far, as shown here:

        root#  id chrisr
        uid=1002(chrisr) gid=513(Domain Users) groups=513(Domain Users)

    This confirms that the UNIX (POSIX) user account information can be resolved from LDAP by system tools that make a getentpw() system call.

13. The root account must have UID=0; if not, this means that operations conducted from a Windows client using tools such as the Domain User Manager fails under UNIX because the management of user and group accounts requires that the UID=0. Additionally, it is a good idea to make certain that no matter how root account credentials are resolved, the home directory and shell are valid. You decide to effect this immediately as demonstrated here:

        root#  cd /opt/IDEALX/sbin
        root#  ./smbldap-usermod -u 0 -d /root -s /bin/bash root

14. Verify that the changes just made to the `root` account were accepted by executing:

        root#  getent passwd | grep root
        root:x:0:0:root:/root:/bin/bash
        root:x:0:512:Netbios Domain Administrator:/root:/bin/bash

    This demonstrates that the changes were accepted.

15. Make certain that a home directory has been created for every user by listing the directories in `/home` as follows:

        root#  ls -al /home
        drwxr-xr-x   8 root   root         176 Dec 17 18:50 ./
        drwxr-xr-x  21 root   root         560 Dec 15 22:19 ../
        drwx------   7 bobj   Domain Users     568 Dec 17 01:16 bobj/
        drwx------   7 chrisr Domain Users     568 Dec 17 01:19 chrisr/
        drwx------   7 maryv  Domain Users     568 Dec 17 01:27 maryv/
        drwx------   7 stans  Domain Users     568 Dec 17 01:43 stans/

    This is precisely what we want to see.

16. The final validation step involves making certain that Samba-3 can obtain the user accounts from the LDAP ldapsam passwd backend. Execute the following command as shown:

        root#  pdbedit -Lv chrisr
        Unix username:        chrisr
        NT username:          chrisr
        Account Flags:        [U          ]
        User SID:             S-1-5-21-3504140859-1010554828-2431957765-3004
        Primary Group SID:    S-1-5-21-3504140859-1010554828-2431957765-513
        Full Name:            System User
        Home Directory:       \\MASSIVE\homes
        HomeDir Drive:        H:
        Logon Script:         scripts\login.cmd
        Profile Path:         \\MASSIVE\profiles\chrisr
        Domain:               MEGANET2
        Account desc:         System User
        Workstations:
        Munged dial:
        Logon time:           0
        Logoff time:          Mon, 18 Jan 2038 20:14:07 GMT
        Kickoff time:         Mon, 18 Jan 2038 20:14:07 GMT
        Password last set:    Wed, 17 Dec 2003 17:17:40 GMT
        Password can change:  Wed, 17 Dec 2003 17:17:40 GMT
        Password must change: Mon, 18 Jan 2038 20:14:07 GMT
        Last bad password   : 0
        Bad password count  : 0
        Logon hours         : FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF

    This looks good. Of course, you fully expected that it would all work, didn't you?

17. Now you add the group accounts that are used on the Abmas network. Execute the following exactly as shown:

        root#  ./smbldap-groupadd -a Accounts
        root#  ./smbldap-groupadd -a Finances
        root#  ./smbldap-groupadd -a PIOps

    The addition of groups does not involve keyboard interaction, so the lack of console output is of no concern.

18. You really do want to confirm that UNIX group resolution from LDAP is functioning as it should. Let's do this as shown here:

        root#  getent group
        ...
        Domain Admins:x:512:root
        Domain Users:x:513:bobj,stans,chrisr,maryv
        Domain Guests:x:514:
        ...
        Accounts:x:1000:
        Finances:x:1001:
        PIOps:x:1002:

    The well-known special accounts (Domain Admins, Domain Users, Domain Guests), as well as our own site-specific group accounts, are correctly listed. This is looking good.

19. The final step we need to validate is that Samba can see all the Windows domain groups and that they are correctly mapped to the respective UNIX group account. To do this, just execute the following command:

        root#  net groupmap list
        Domain Admins (S-1-5-21-3504140859-...-2431957765-512) -> Domain Admins
        Domain Users (S-1-5-21-3504140859-...-2431957765-513) -> Domain Users
        Domain Guests (S-1-5-21-3504140859-...-2431957765-514) -> Domain Guests
        ...
        Accounts (S-1-5-21-3504140859-1010554828-2431957765-3001) -> Accounts
        Finances (S-1-5-21-3504140859-1010554828-2431957765-3003) -> Finances
        PIOps (S-1-5-21-3504140859-1010554828-2431957765-3005) -> PIOps

    This is looking good. Congratulations it works! Note that in the above output the lines were shortened by replacing the middle value (1010554828) of the SID with the ellipsis (...).

20. The server you have so carefully built is now ready for another important step. You start the Samba-3 server and validate its operation. Execute the following to render all the processes needed fully operative so that, on system reboot, they are automatically started:

        root#  chkconfig named on
        root#  chkconfig dhcpd on
        root#  chkconfig ldap on
        root#  chkconfig nmb on
        root#  chkconfig smb on
        root#  chkconfig winbind on
        root#  rcnmb start
        root#  rcsmb start
        root#  rcwinbind start

21. The next step might seem a little odd at this point, but take note that you are about to start `winbindd`, which must be able to authenticate to the PDC via the localhost interface with the `smbd` process. This account can be easily created by joining the PDC to the domain by executing the following command:

        root#  net rpc join -S MASSIVE -U root%not24get

    Note: Before executing this command on the PDC, both `nmbd` and `smbd` must be started so that the `net` command can communicate with `smbd`. The expected output is as follows:

        Joined domain MEGANET2.

    This indicates that the domain security account for the PDC has been correctly created.

22. At this time it is necessary to restart `winbindd` so that it can correctly authenticate to the PDC. The following command achieves that:

        root#  rcwinbind restart

23. You may now check Samba-3 operation as follows:

        root#  smbclient -L massive -U%

                Sharename      Type      Comment
                ---------      ----      -------
                IPC$           IPC       IPC Service (Samba 3.0.20)
                accounts       Disk      Accounting Files
                service        Disk      Financial Services Files
                pidata         Disk      Property Insurance Files
                apps           Disk      Application Files
                netlogon       Disk      Network Logon Service
                profiles       Disk      Profile Share
                profdata       Disk      Profile Data Share
                ADMIN$         IPC       IPC Service (Samba 3.0.20)

                Server               Comment
                ---------            -------
                MASSIVE              Samba 3.0.20

                Workgroup            Master
                ---------            -------
                MEGANET2             MASSIVE

    This shows that an anonymous connection is working.

24. For your finale, let's try an authenticated connection:

        root#  smbclient //massive/bobj -Ubobj%n3v3r2l8
        smb: \> dir
          .                    D        0  Wed Dec 17 01:16:19 2003
          ..                   D        0  Wed Dec 17 19:04:42 2003
          bin                  D        0  Tue Sep  2 04:00:57 2003
          Documents            D        0  Sun Nov 30 07:28:20 2003
          public_html          D        0  Sun Nov 30 07:28:20 2003
          .urlview             H      311  Fri Jul  7 06:55:35 2000
          .dvipsrc             H      208  Fri Nov 17 11:22:02 1995

                  57681 blocks of size 524288. 57128 blocks available
        smb: \> q

    Well done. All is working fine.

The server `MASSIVE` is now configured, and it is time to move onto the next task.

### Printer Configuration

The configuration for Samba-3 to enable CUPS raw-print-through printing has already been taken care of in the `smb.conf` file. The only preparation needed for `smart` printing to be possible involves creation of the directories in which Samba-3 stores Windows printing driver files.

Procedure 5.9. Printer Configuration Steps

1. Configure all network-attached printers to have a fixed IP address.

2. Create an entry in the DNS database on the server `MASSIVE` in both the forward lookup database for the zone `abmas.biz.hosts` and in the reverse lookup database for the network segment that the printer is to be located in. Example configuration files for similar zones were presented in “Secure Office Networking”, “DNS Abmas.biz Forward Zone File” and in “DNS 192.168.2 Reverse Zone File”.

3. Follow the instructions in the printer manufacturers' manuals to permit printing to port 9100. Use any other port the manufacturer specifies for direct mode, raw printing. This allows the CUPS spooler to print using raw mode protocols.

4. Only on the server to which the printer is attached, configure the CUPS Print Queues as follows:

       root#  lpadmin -p printque
       	 -v socket://printer-name.abmas.biz:9100 -E

   This step creates the necessary print queue to use no assigned print filter. This is ideal for raw printing, that is, printing without use of filters. The name `printque` is the name you have assigned for the particular printer.

5. Print queues may not be enabled at creation. Make certain that the queues you have just created are enabled by executing the following:

       root#  /usr/bin/enable printque

6. Even though your print queue may be enabled, it is still possible that it may not accept print jobs. A print queue will service incoming printing requests only when configured to do so. Ensure that your print queue is set to accept incoming jobs by executing the following commands:

       root#  /usr/bin/accept printque

7. Edit the file `/etc/cups/mime.convs` to uncomment the line:

       application/octet-stream     application/vnd.cups-raw      0     -

8. Edit the file `/etc/cups/mime.types` to uncomment the line:

       application/octet-stream

9. Refer to the CUPS printing manual for instructions regarding how to configure CUPS so that print queues that reside on CUPS servers on remote networks route print jobs to the print server that owns that queue. The default setting on your CUPS server may automatically discover remotely installed printers and may permit this functionality without requiring specific configuration.

10. The following action creates the necessary directory subsystem. Follow these steps to printing heaven:

        root#  mkdir -p /var/lib/samba/drivers/{W32ALPHA,W32MIPS,W32X86,WIN40}
        root#  chown -R root:root /var/lib/samba/drivers
        root#  chmod -R ug=rwx,o=rx /var/lib/samba/drivers

## Samba-3 BDC Configuration

Procedure 5.10. Configuration of BDC Called: `BLDG1`

1. Install the files in “LDAP Based smb.conf File, Server: BLDG1”, “LDAP Based smb.conf File, Shares Section Part A”, and “LDAP Based smb.conf File, Shares Section Part B” into the `/etc/samba/` directory. The three files should be added together to form the `smb.conf` file.

2. Verify the `smb.conf` file as in step 2 of “Samba-3 PDC Configuration”.

3. Carefully follow the steps outlined in “PAM and NSS Client Configuration”, taking particular note to install the correct `ldap.conf`.

4. Verify that the NSS resolver is working. You may need to cycle the run level to 1 and back to 5 before the NSS LDAP resolver functions. Follow these commands:

       root#  init 1

   After the run level has been achieved, you are prompted to provide the `root` password. Log on, and then execute:

       root#  init 5

   When the normal logon prompt appears, log into the system as `root` and then execute these commands:

       root#  getent passwd
       root:x:0:0:root:/root:/bin/bash
       bin:x:1:1:bin:/bin:/bin/bash
       daemon:x:2:2:Daemon:/sbin:/bin/bash
       lp:x:4:7:Printing daemon:/var/spool/lpd:/bin/bash
       mail:x:8:12:Mailer daemon:/var/spool/clientmqueue:/bin/false
       ...
       root:x:0:512:Netbios Domain Administrator:/root:/bin/bash
       nobody:x:999:514:nobody:/dev/null:/bin/false
       bobj:x:1000:513:System User:/home/bobj:/bin/bash
       stans:x:1001:513:System User:/home/stans:/bin/bash
       chrisr:x:1002:513:System User:/home/chrisr:/bin/bash
       maryv:x:1003:513:System User:/home/maryv:/bin/bash
       vaioboss$:x:1005:553:vaioboss$:/dev/null:/bin/false
       bldg1$:x:1006:553:bldg1$:/dev/null:/bin/false

   This is the correct output. If the accounts that have UIDs above 512 are not shown, there is a problem.

5. The next step in the verification process involves testing the operation of UNIX group resolution via the NSS LDAP resolver. Execute these commands:

       root#  getent group
       root:x:0:
       bin:x:1:daemon
       daemon:x:2:
       sys:x:3:
       ...
       Domain Admins:x:512:root
       Domain Users:x:513:bobj,stans,chrisr,maryv,jht
       Domain Guests:x:514:
       Administrators:x:544:
       Users:x:545:
       Guests:x:546:nobody
       Power Users:x:547:
       Account Operators:x:548:
       Server Operators:x:549:
       Print Operators:x:550:
       Backup Operators:x:551:
       Replicator:x:552:
       Domain Computers:x:553:
       Accounts:x:1000:
       Finances:x:1001:
       PIOps:x:1002:

   This is also the correct and desired output, because it demonstrates that the LDAP client is able to communicate correctly with the LDAP server (`MASSIVE`).

6. You must now set the LDAP administrative password into the Samba-3 `secrets.tdb` file by executing this command:

       root#  smbpasswd -w not24get
       Setting stored password for "cn=Manager,dc=abmas,dc=biz" in secrets.tdb

7. Now you must obtain the domain SID from the PDC and store it into the `secrets.tdb` file also. This step is not necessary with an LDAP passdb backend because Samba-3 obtains the domain SID from the sambaDomain object it automatically stores in the LDAP backend. It does not hurt to add the SID to the `secrets.tdb`, and if you wish to do so, this command can achieve that:

       root#  net rpc getsid MEGANET2
       Storing SID S-1-5-21-3504140859-1010554828-2431957765 \
                                  for Domain MEGANET2 in secrets.tdb

   When configuring a Samba-3 BDC that has an LDAP backend, there is no need to take any special action to join it to the domain. However, winbind communicates with the domain controller that is running on the localhost and must be able to authenticate, thus requiring that the BDC should be joined to the domain. The process of joining the domain creates the necessary authentication accounts.

8. To join the Samba BDC to the domain, execute the following:

       root#  net rpc join -U root%not24get
       Joined domain MEGANET2.

   This indicates that the domain security account for the BDC has been correctly created.

9. Verify that user and group account resolution works via Samba-3 tools as follows:

       root#  pdbedit -L
       root:0:root
       nobody:65534:nobody
       bobj:1000:System User
       stans:1001:System User
       chrisr:1002:System User
       maryv:1003:System User
       bldg1$:1006:bldg1$

       root#  net groupmap list
       Domain Admins (S-1-5-21-3504140859-...-2431957765-512) ->
                                                               Domain Admins
       Domain Users (S-1-5-21-3504140859-...-2431957765-513) -> Domain Users
       Domain Guests (S-1-5-21-3504140859-...-2431957765-514) ->
                                                               Domain Guests
       Administrators (S-1-5-21-3504140859-...-2431957765-544) ->
                                                              Administrators
       ...
       Accounts (S-1-5-21-3504140859-1010554828-2431957765-3001) -> Accounts
       Finances (S-1-5-21-3504140859-1010554828-2431957765-3003) -> Finances
       PIOps (S-1-5-21-3504140859-1010554828-2431957765-3005) -> PIOps

   These results show that all things are in order.

10. The server you have so carefully built is now ready for another important step. Now start the Samba-3 server and validate its operation. Execute the following to render all the processes needed fully operative so that, upon system reboot, they are automatically started:

        root#  chkconfig named on
        root#  chkconfig dhcpd on
        root#  chkconfig nmb on
        root#  chkconfig smb on
        root#  chkconfig winbind on
        root#  rcnmb start
        root#  rcsmb start
        root#  rcwinbind start

    Samba-3 should now be running and is ready for a quick test. But not quite yet!

11. Your new `BLDG1, BLDG2` servers do not have home directories for users. To rectify this using the SUSE yast2 utility or by manually editing the `/etc/fstab` file, add a mount entry to mount the `home` directory that has been exported from the `MASSIVE` server. Mount this resource before proceeding. An alternate approach could be to create local home directories for users who are to use these machines. This is a choice that you, as system administrator, must make. The following entry in the `/etc/fstab` file suffices for now:

        massive.abmas.biz:/home  /home  nfs     rw 0 0

    To mount this resource, execute:

        root#  mount -a

    Verify that the home directory has been mounted as follows:

        root#  df | grep home
        massive:/home         29532988    283388  29249600   1% /home

12. Implement a quick check using one of the users that is in the LDAP database. Here you go:

        root#  smbclient //bldg1/bobj -Ubobj%n3v3r2l8
        smb: \> dir
          .                    D        0  Wed Dec 17 01:16:19 2003
          ..                   D        0  Wed Dec 17 19:04:42 2003
          bin                  D        0  Tue Sep  2 04:00:57 2003
          Documents            D        0  Sun Nov 30 07:28:20 2003
          public_html          D        0  Sun Nov 30 07:28:20 2003
          .urlview             H      311  Fri Jul  7 06:55:35 2000
          .dvipsrc             H      208  Fri Nov 17 11:22:02 1995

                  57681 blocks of size 524288. 57128 blocks available
        smb: \> q

Now that the first BDC (`BDLG1`) has been configured it is time to build and configure the second BDC server (`BLDG2`) as follows:

Procedure 5.11. Configuration of BDC Called `BLDG2`

1. Install the files in “LDAP Based smb.conf File, Server: BLDG2”, “LDAP Based smb.conf File, Shares Section Part A”, and “LDAP Based smb.conf File, Shares Section Part B” into the `/etc/samba/` directory. The three files should be added together to form the `smb.conf` file.

2. Follow carefully the steps shown in “Samba-3 BDC Configuration”, starting at step 2.

Example 5.8. LDAP Based `smb.conf` File, Server: BLDG1

# Global parameters
`[global]`
`unix charset = LOCALE`
`workgroup = MEGANET2`
`netbios name = BLDG1`
`passdb backend = ldapsam:ldap://massive.abmas.biz`
`enable privileges = Yes`
`username map = /etc/samba/smbusers`
`log level = 1`
`syslog = 0`
`log file = /var/log/samba/%m`
`max log size = 50`
`smb ports = 139`
`name resolve order = wins bcast hosts`
`printcap name = CUPS`
`show add printer wizard = No`
`logon script = scripts\logon.bat`
`logon path = \\%L\profiles\%U`
`logon drive = X:`
`domain logons = Yes`
`domain master = No`
`wins server = 172.16.0.1`
`ldap suffix = dc=abmas,dc=biz`
`ldap machine suffix = ou=People`
`ldap user suffix = ou=People`
`ldap group suffix = ou=Groups`
`ldap idmap suffix = ou=Idmap`
`ldap admin dn = cn=Manager,dc=abmas,dc=biz`
`idmap backend = ldap:ldap://massive.abmas.biz`
`idmap uid = 10000-20000`
`idmap gid = 10000-20000`
`printing = cups`
`printer admin = root, chrisr`

Example 5.9. LDAP Based `smb.conf` File, Server: BLDG2

# Global parameters
`[global]`
`unix charset = LOCALE`
`workgroup = MEGANET2`
`netbios name = BLDG2`
`passdb backend = ldapsam:ldap://massive.abmas.biz`
`enable privileges = Yes`
`username map = /etc/samba/smbusers`
`log level = 1`
`syslog = 0`
`log file = /var/log/samba/%m`
`max log size = 50`
`smb ports = 139`
`name resolve order = wins bcast hosts`
`printcap name = CUPS`
`show add printer wizard = No`
`logon script = scripts\logon.bat`
`logon path = \\%L\profiles\%U`
`logon drive = X:`
`domain logons = Yes`
`domain master = No`
`wins server = 172.16.0.1`
`ldap suffix = dc=abmas,dc=biz`
`ldap machine suffix = ou=People`
`ldap user suffix = ou=People`
`ldap group suffix = ou=Groups`
`ldap idmap suffix = ou=Idmap`
`ldap admin dn = cn=Manager,dc=abmas,dc=biz`
`idmap backend = ldap:ldap://massive.abmas.biz`
`idmap uid = 10000-20000`
`idmap gid = 10000-20000`
`printing = cups`
`printer admin = root, chrisr`

Example 5.10. LDAP Based `smb.conf` File, Shares Section Part A

`[accounts]`
`comment = Accounting Files`
`path = /data/accounts`
`read only = No`
`[service]`
`comment = Financial Services Files`
`path = /data/service`
`read only = No`
`[pidata]`
`comment = Property Insurance Files`
`path = /data/pidata`
`read only = No`
`[homes]`
`comment = Home Directories`
`valid users = %S`
`read only = No`
`browseable = No`
`[printers]`
`comment = SMB Print Spool`
`path = /var/spool/samba`
`guest ok = Yes`
`printable = Yes`
`browseable = No`

Example 5.11. LDAP Based `smb.conf` File, Shares Section Part B

`[apps]`
`comment = Application Files`
`path = /apps`
`admin users = bjordan`
`read only = No`
`[netlogon]`
`comment = Network Logon Service`
`path = /var/lib/samba/netlogon`
`guest ok = Yes`
`locking = No`
`[profiles]`
`comment = Profile Share`
`path = /var/lib/samba/profiles`
`read only = No`
`profile acls = Yes`
`[profdata]`
`comment = Profile Data Share`
`path = /var/lib/samba/profdata`
`read only = No`
`profile acls = Yes`
`[print$]`
`comment = Printer Drivers`
`path = /var/lib/samba/drivers`
`browseable = yes`
`guest ok = no`
`read only = yes`
`write list = root, chrisr`

Example 5.12. LDIF IDMAP Add-On Load File File: /etc/openldap/idmap.LDIF

    dn: ou=Idmap,dc=abmas,dc=biz
    objectClass: organizationalUnit
    ou: idmap
    structuralObjectClass: organizationalUnit

## Miscellaneous Server Preparation Tasks

My father would say, “Dinner is not over until the dishes have been done.” The makings of a great network environment take a lot of effort and attention to detail. So far, you have completed most of the complex (and to many administrators, the interesting part of server configuration) steps, but remember to tie it all together. Here are a few more steps that must be completed so that your network runs like a well-rehearsed orchestra.

### Configuring Directory Share Point Roots

In your `smb.conf` file, you have specified Windows shares. Each has a `path` parameter. Even though it is obvious to all, one of the common Samba networking problems is caused by forgetting to verify that every such share root directory actually exists and that it has the necessary permissions and ownership.

Here is an example, but remember to create the directory needed for every share:

    root#  mkdir -p /data/{accounts,finsvcs,piops}
    root#  mkdir -p /apps
    root#  chown -R root:root /data
    root#  chown -R root:root /apps
    root#  chown -R bobj:Accounts /data/accounts
    root#  chown -R bobj:Finances /data/finsvcs
    root#  chown -R bobj:PIOps /data/piops
    root#  chmod -R ug+rwxs,o-rwx /data
    root#  chmod -R ug+rwx,o+rx-w /apps

### Configuring Profile Directories

You made a conscious decision to do everything it would take to improve network client performance. One of your decisions was to implement folder redirection. This means that Windows user desktop profiles are now made up of two components: a dynamically loaded part and a set of file network folders.

For this arrangement to work, every user needs a directory structure for the network folder portion of his or her profile as shown here:

    root#  mkdir -p /var/lib/samba/profdata
    root#  chown root:root /var/lib/samba/profdata
    root#  chmod 755 /var/lib/samba/profdata

    # Per user structure
    root#  cd /var/lib/samba/profdata
    root#  mkdir -p username
    root#  for i in InternetFiles Cookies History AppData \
                          LocalSettings MyPictures MyDocuments Recent
    root#  do
    root#  mkdir username/$i
    root#  done
    root#  chown -R username:Domain\ Users username
    root#  chmod -R 750 username

You have three options insofar as the dynamically loaded portion of the roaming profile is concerned:

- You may permit the user to obtain a default profile.

- You can create a mandatory profile.

- You can create a group profile (which is almost always a mandatory profile).

Mandatory profiles cannot be overwritten by a user. The change from a user profile to a mandatory profile is effected by renaming the `NTUSER.DAT` to `NTUSER.MAN`, that is, just by changing the filename extension.

The location of the profile that a user can obtain is set in the user's account in the LDAP passdb backend. You can manage this using the Idealx smbldap-tools or using the Windows NT4 Domain User Manager.

It may not be obvious that you must ensure that the root directory for the user's profile exists and has the needed permissions. Use the following commands to create this directory:

    root#  mkdir -p /var/lib/samba/profiles/username
    root#  chown username:Domain\ Users
    	    /var/lib/samba/profiles/username
    root#  chmod 700  /var/lib/samba/profiles/username

### Preparation of Logon Scripts

The use of a logon script with Windows XP Professional is an option that every site should consider. Unless you have locked down the desktop so the user cannot change anything, there is risk that a vital network drive setting may be broken or that printer connections may be lost. Logon scripts can help to restore persistent network folder (drive) and printer connections in a predictable manner. One situation in which such breakage may occur in particular is when a mobile PC (notebook) user attaches to another company's network that forces environment changes that are alien to your network.

If you decide to use network logon scripts, by reference to the `smb.conf` files for the domain controllers, you see that the path to the share point for the `NETLOGON` share defined is `/var/lib/samba/netlogon`. The path defined for the logon script inside that share is `scripts\logon.bat`. This means that as a Windows NT/200x/XP client logs onto the network, it tries to obtain the file `logon.bat` from the fully qualified path `/var/lib/samba/netlogon/scripts`. This fully qualified path should therefore exist whether you install the `logon.bat`.

You can, of course, create the fully qualified path by executing:

    root#  mkdir -p /var/lib/samba/netlogon/scripts

You should research the options for logon script implementation by referring to TOSHARG2, Chapter 24, Section 24.4. A quick Web search will bring up a host of options. One of the most popular logon facilities in use today is called KiXtart.

### Assigning User Rights and Privileges

The ability to perform tasks such as joining Windows clients to the domain can be assigned to normal user accounts. By default, only the domain administrator account (`root` on UNIX systems because it has UID=0) can add accounts. New to Samba 3.0.11 is the ability to grant this privilege in a very limited fashion to particular accounts.

By default, even Samba-3.0.11 does not grant any rights even to the `Domain Admins` group. Here we grant this group all privileges.

Samba limits privileges on a per-server basis. This is a deliberate limitation so that users who are granted rights can be restricted to particular machines. It is left to the network administrator to determine which rights should be provided and to whom.

Procedure 5.12. Steps for Assignment of User Rights and Privileges

1. Log onto the PDC as the `root` account.

2. Execute the following command to grant the `Domain Admins` group all rights and privileges:

       root#  net -S MASSIVE  -U root%not24get rpc rights grant \
               "MEGANET2\Domain Admins" SeMachineAccountPrivilege \
       	SePrintOperatorPrivilege SeAddUsersPrivilege \
       	SeDiskOperatorPrivilege SeRemoteShutdownPrivilege
       Successfully granted rights.

   Repeat this step on each domain controller, in each case substituting the name of the server (e.g., BLDG1, BLDG2) in place of the PDC called MASSIVE.

3. In this step the privilege will be granted to Bob Jordan (bobj) to add Windows workstations to the domain. Execute the following only on the PDC. It is not necessary to do this on BDCs or on DMS machines because machine accounts are only ever added by the PDC:

       root#  net -S MASSIVE  -U root%not24get rpc rights grant \
                    "MEGANET2\bobj" SeMachineAccountPrivilege
       Successfully granted rights.

4. Verify that privilege assignments have been correctly applied by executing:

       net rpc rights list accounts -Uroot%not24get
       MEGANET2\bobj
       SeMachineAccountPrivilege

       S-0-0
       No privileges assigned

       BUILTIN\Print Operators
       No privileges assigned

       BUILTIN\Account Operators
       No privileges assigned

       BUILTIN\Backup Operators
       No privileges assigned

       BUILTIN\Server Operators
       No privileges assigned

       BUILTIN\Administrators
       No privileges assigned

       Everyone
       No privileges assigned

       MEGANET2\Domain Admins
       SeMachineAccountPrivilege
       SePrintOperatorPrivilege
       SeAddUsersPrivilege
       SeRemoteShutdownPrivilege
       SeDiskOperatorPrivilege

## Windows Client Configuration

In the next few sections, you can configure a new Windows XP Professional disk image on a staging machine. You will configure all software, printer settings, profile and policy handling, and desktop default profile settings on this system. When it is complete, you copy the contents of the `C:\Documents and Settings\Default User` directory to a directory with the same name in the `NETLOGON` share on the domain controllers.

Much can be learned from the Microsoft Support site regarding how best to set up shared profiles. One knowledge-base article in particular stands out: "How to Create a Base Profile for All Users."

### Configuration of Default Profile with Folder Redirection

Log onto the Windows XP Professional workstation as the local `Administrator`. It is necessary to expose folders that are generally hidden to provide access to the `Default User` folder.

Procedure 5.13. Expose Hidden Folders

1. Launch the Windows Explorer by clicking Start → My Computer → Tools → Folder Options → View Tab. Select Show hidden files and folders, and click OK. Exit Windows Explorer.

2. Launch the Registry Editor. Click Start → Run. Key in `regedt32`, and click OK.

Procedure 5.14. Redirect Folders in Default System User Profile

1. Give focus to `HKEY_LOCAL_MACHINE` hive entry in the left panel. Click File → Load Hive... → Documents and Settings → Default User → NTUSER → Open. In the dialog box that opens, enter the key name `Default` and click OK.

2. Browse inside the newly loaded Default folder to:

       HKEY_LOCAL_MACHINE\Default\Software\Microsoft\Windows\
                            CurrentVersion\Explorer\User Shell Folders\

   The right panel reveals the contents as shown in “Windows XP Professional User Shared Folders”.

3. You edit hive keys. Acceptable values to replace the `%USERPROFILE%` variable includes:

   - A drive letter such as `U:`

   - A direct network path such as `\\MASSIVE\profdata`

   - A network redirection (UNC name) that contains a macro such as

     `%LOGONSERVER%\profdata\`

4. Set the registry keys as shown in “Default Profile Redirections”. Your implementation makes the assumption that users have statically located machines. Notebook computers (mobile users) need to be accommodated using local profiles. This is not an uncommon assumption.

5. Click back to the root of the loaded hive `Default`. Click File → Unload Hive... → Yes.

6. Click File → Exit. This exits the Registry Editor.

7. Now follow the procedure given in “The Local Group Policy”. Make sure that each folder you have redirected is in the exclusion list.

8. You are now ready to copy[11] the Default User profile to the Samba domain controllers. Launch Microsoft Windows Explorer, and use it to copy the full contents of the directory `Default User` that is in the `C:\Documents and Settings` to the root directory of the `NETLOGON` share. If the `NETLOGON` share has the defined UNIX path of `/var/lib/samba/netlogon`, when the copy is complete there must be a directory in there called `Default User`.

Before punching out new desktop images for the client workstations, it is perhaps a good idea that desktop behavior should be returned to the original Microsoft settings. The following steps achieve that ojective:

Procedure 5.15. Reset Folder Display to Original Behavior

- To launch the Windows Explorer, click Start → My Computer → Tools → Folder Options → View Tab. Deselect Show hidden files and folders, and click OK. Exit Windows Explorer.

Figure 5.3. Windows XP Professional User Shared Folders

Table 5.4. Default Profile Redirections

Registry Key | Redirected Value
--- | ---
Cache | %LOGONSERVER%\profdata\%USERNAME%\InternetFiles
Cookies | %LOGONSERVER%\profdata\%USERNAME%\Cookies
History | %LOGONSERVER%\profdata\%USERNAME%\History
Local AppData | %LOGONSERVER%\profdata\%USERNAME%\AppData
Local Settings | %LOGONSERVER%\profdata\%USERNAME%\LocalSettings
My Pictures | %LOGONSERVER%\profdata\%USERNAME%\MyPictures
Personal | %LOGONSERVER%\profdata\%USERNAME%\MyDocuments
Recent | %LOGONSERVER%\profdata\%USERNAME%\Recent

### Configuration of MS Outlook to Relocate PST File

Microsoft Outlook can store a Personal Storage file, generally known as a PST file. It is the nature of email storage that this file grows, at times quite rapidly. So that users' email is available to them at every workstation they may log onto, it is common practice in well-controlled sites to redirect the PST folder to the users' home directory. Follow these steps for each user who wishes to do this.

To redirect the Outlook PST file in Outlook 2003 (older versions of Outlook behave slightly differently), follow these steps:

Procedure 5.16. Outlook PST File Relocation

1. Close Outlook if it is open.

2. From the Control Panel, launch the Mail icon.

3. Click Email Accounts.

4. Make a note of the location of the PST file(s). From this location, move the files to the desired new target location. The most desired new target location may well be the users' home directory.

5. Add a new data file, selecting the PST file in the new desired target location. Give this entry (not the filename) a new name such as “Personal Mail Folders.”

   Note: If MS Outlook has been configured to use an IMAP account configuration there may be problems following these instructions. Feedback from users suggests that where IMAP is used the PST file is used to store rules and filters. When the PST store is relocated it appears to break MS Outlook's Send/Receive button. If anyone has successfully relocated PST files where IMAP is used please email `jht@samba.org` with useful tips and suggestions so that this warning can be removed or modified.

6. Close the Date Files windows, then click Email Accounts.

7. Select View of Change exiting email accounts, click Next.

8. Change the Mail Delivery Location so as to use the data file in the new target location.

9. Go back to the Data Files window, then delete the old data file entry.

### Note

You may have to remove and reinstall the Outlook Address Book (Contacts) entries, otherwise the user may be not be able to retrieve contacts when addressing a new email message.

### Note

Outlook Express is not at all like MS OutLook. It stores file very differently also. Outlook Express storage files can not be redirected to network shares. The options panel will not permit this, but they can be moved to folders outside of the user's profile. They can also be excluded from folder synchronization as part of the roaming profile.

While it is possible to redirect the data stores for Outlook Express data stores by editing the registry, experience has shown that data corruption and loss of email messages will result.

In the same vane as MS Outlook, Outlook Express data stores can become very large. When used with roaming profiles this can result in excruciatingly long login and logout behavior will files are synchronized. For this reason, it is highly recommended not to use Outlook Express where roaming profiles are used.

Microsoft does not support storing PST files on network shares, although the practice does appear to be rather popular. Anyone who does relocation the PST file to a network resource should refer the Microsoft reference to better understand the issues.

Apart from manually moving PST files to a network share, it is possible to set the default PST location for new accounts by following the instructions at the WindowsITPro web site.

User feedback suggests that disabling of oplocks on PST files will significantly improve network performance by reducing locking overheads. One way this can be done is to add to the `smb.conf` file stanza for the share the PST file the following:

    veto oplock files = /*.pdf/*.PST/

### Configure Delete Cached Profiles on Logout

Configure the Windows XP Professional client to auto-delete roaming profiles on logout:

Click Start → Run. In the dialog box, enter `MMC` and click OK.

Follow these steps to set the default behavior of the staging machine so that all roaming profiles are deleted as network users log out of the system. Click File → Add/Remove Snap-in → Add → Group Policy → Add → Finish → Close → OK.

The Microsoft Management Console now shows the Group Policy utility that enables you to set the policies needed. In the left panel, click Local Computer Policy → Administrative Templates → System → User Profiles. In the right panel, set the properties shown here by double-clicking on each item as shown:

- Do not check for user ownership of Roaming Profile Folders = Enabled

- Delete cached copies of roaming profiles = Enabled

Close the Microsoft Management Console. The settings take immediate effect and persist onto all image copies made of this system to deploy the new standard desktop system.

### Uploading Printer Drivers to Samba Servers

Users want to be able to use network printers. You have a vested interest in making it easy for them to print. You have chosen to install the printer drivers onto the Samba servers and to enable point-and-click (drag-and-drop) printing. This process results in Samba being able to automatically provide the Windows client with the driver necessary to print to the printer chosen. The following procedure must be followed for every network printer:

Procedure 5.17. Steps to Install Printer Drivers on the Samba Servers

1. Join your Windows XP Professional workstation (the staging machine) to the `MEGANET2` domain. If you are not sure of the procedure, follow the guidance given in “A Collection of Useful Tidbits”, “Joining a Domain: Windows 200x/XP Professional”.

2. After the machine has rebooted, log onto the workstation as the domain `root` (this is the Administrator account for the operating system that is the host platform for this implementation of Samba.

3. Launch MS Windows Explorer. Navigate in the left panel. Click My Network Places → Entire Network → Microsoft Windows Network → Meganet2 → Massive. Click on Massive Printers and Faxes.

4. Identify a printer that is shown in the right panel. Let us assume the printer is called `ps01-color`. Right-click on the ps01-color icon and select the Properties entry. This opens a dialog box that indicates that “The printer driver is not installed on this computer. Some printer properties will not be accessible unless you install the printer driver. Do you want to install the driver now?” It is important at this point you answer No.

5. The printer properties panel for the ps01-color printer on the server `MASSIVE` is displayed. Click the Advanced tab. Note that the box labeled Driver is empty. Click the New Driver button that is next to the Driver box. This launches the “Add Printer Wizard”.

6. The “Add Printer Driver Wizard on `MASSIVE`” panel is now presented. Click Next to continue. From the left panel, select the printer manufacturer. In your case, you are adding a driver for a printer manufactured by Lexmark. In the right panel, select the printer (Lexmark Optra Color 40 PS). Click Next, and then Finish to commence driver upload. A progress bar appears and instructs you as each file is being uploaded and that it is being directed at the network server `\\massive\ps01-color`.

7. The driver upload completes in anywhere from a few seconds to a few minutes. When it completes, you are returned to the Advanced tab in the Properties panel. You can set the Location (under the General tab) and Security settings (under the Security tab). Under the Sharing tab it is possible to load additional printer drivers; there is also a check-box in this tab called “List in the directory”. When this box is checked, the printer will be published in Active Directory (Applicable to Active Directory use only.)

8. Click OK. It will take a minute or so to upload the settings to the server. You are now returned to the Printers and Faxes on Massive monitor. Right-click on the printer, click Properties → Device Settings. Now change the settings to suit your requirements. BE CERTAIN TO CHANGE AT LEAST ONE SETTING and apply the changes even if you need to reverse the changes back to their original settings.

9. This is necessary so that the printer settings are initialized in the Samba printers database. Click Apply to commit your settings. Revert any settings you changed just to initialize the Samba printers database entry for this printer. If you need to revert a setting, click Apply again.

10. Verify that all printer settings are at the desired configuration. When you are satisfied that they are, click the General tab. Now click the Print Test Page button. A test page should print. Verify that it has printed correctly. Then click OK in the panel that is newly presented. Click OK on the ps01-color on massive Properties panel.

11. You must repeat this process for all network printers (i.e., for every printer on each server). When you have finished uploading drivers to all printers, close all applications. The next task is to install software your users require to do their work.

### Software Installation

Your network has both fixed desktop workstations as well as notebook computers. As a general rule, it is a good idea to not tamper with the operating system that is provided by the notebook computer manufacturer. Notebooks require special handling that is beyond the scope of this chapter.

For desktop systems, the installation of software onto administratively centralized application servers make a lot of sense. This means that you can manage software maintenance from a central perspective and that only minimal application stubware needs to be installed onto the desktop systems. You should proceed with software installation and default configuration as far as is humanly possible and so long as it makes sense to do so. Make certain to thoroughly test and validate every aspect of software operations and configuration.

When you believe that the overall configuration is complete, be sure to create a shared group profile and migrate that to the Samba server for later reuse when creating custom mandatory profiles, just in case a user may have specific needs you had not anticipated.

### Roll-out Image Creation

The final steps before preparing the distribution Norton Ghost image file you might follow are:

> Unjoin the domain Each workstation requires a unique name and must be independently joined into domain membership.

> Defragment the hard disk While not obvious to the uninitiated, defragmentation results in better performance and often significantly reduces the size of the compressed disk image. That also means it will take less time to deploy the image onto 500 workstations.

## Key Points Learned

This chapter introduced many new concepts. Is it a sad fact that the example presented deliberately avoided any consideration of security. Security does not just happen; you must design it into your total network. Security begins with a systems design and implementation that anticipates hostile behavior from users both inside and outside the organization. Hostile and malicious intruders do not respect barriers; they accept them as challenges. For that reason, if not simply from a desire to establish safe networking practices, you must not deploy the design presented in this book in an environment where there is risk of compromise.

As a minimum, the LDAP server must be protected by way of Access Control Lists (ACLs), and it must be configured to use secure protocols for all communications over the network. Of course, secure networking does not result just from systems design and implementation but involves constant user education training and, above all, disciplined attention to detail and constant searching for signs of unfriendly or alien activities. Security is itself a topic for a whole book. Please do consult appropriate sources. Jerry Carter's book LDAP System Administration is a good place to start reading about OpenLDAP as well as security considerations.

The substance of this chapter that has been deserving of particular attention includes:

- Implementation of an OpenLDAP-based passwd backend, necessary to support distributed domain control.

- Implementation of Samba primary and secondary domain controllers with a common LDAP backend for user and group accounts that is shared with the UNIX system through the PADL nss_ldap and pam_ldap tool-sets.

- Use of the Idealx smbldap-tools scripts for UNIX (POSIX) account management as well as to manage Samba Windows user and group accounts.

- The basics of implementation of Group Policy controls for Windows network clients.

- Control over roaming profiles, with particular focus on folder redirection to network drives.

- Use of the CUPS printing system together with Samba-based printer driver auto-download.

## Questions and Answers

Well, here we are at the end of this chapter and we have only ten questions to help you to remember so much. There are bound to be some sticky issues here.

Why did you not cover secure practices? Isn't it rather irresponsible to instruct network administrators to implement insecure solutions?
You have focused much on SUSE Linux and little on the market leader, Red Hat. Do you have a problem with Red Hat Linux? Doesn't that make your guidance irrelevant to the Linux I might be using?
You did not use SWAT to configure Samba. Is there something wrong with it?
You have exposed a well-used password not24get. Is that not irresponsible?
The Idealx smbldap-tools create many domain group accounts that are not used. Is that a good thing?
Can I use LDAP just for Samba accounts and not for UNIX system accounts?
Why are the Windows domain RID portions not the same as the UNIX UID?
Printer configuration examples all show printing to the HP port 9100. Does this mean that I must have HP printers for these solutions to work?
Is folder redirection dangerous? I've heard that you can lose your data that way.
Is it really necessary to set a local Group Policy to exclude the redirected folders from the roaming profile?

| Why did you not cover secure practices? Isn't it rather irresponsible to instruct network administrators to implement insecure solutions?

Let's get this right. This is a book about Samba, not about OpenLDAP and secure communication protocols for subjects other than Samba. Earlier on, you note, that the dynamic DNS and DHCP solutions also used no protective secure communications protocols. The reason for this is simple: There are so many ways of implementing secure protocols that this book would have been even larger and more complex.

The solutions presented here all work (at least they did for me). Network administrators have the interest and the need to be better trained and instructed in secure networking practices and ought to implement safe systems. I made the decision, right or wrong, to keep this material as simple as possible. The intent of this book is to demonstrate a working solution and not to discuss too many peripheral issues.

This book makes little mention of backup techniques. Does that mean that I am recommending that you should implement a network without provision for data recovery and for disaster management? Back to our focus: The deployment of Samba has been clearly demonstrated.

| You have focused much on SUSE Linux and little on the market leader, Red Hat. Do you have a problem with Red Hat Linux? Doesn't that make your guidance irrelevant to the Linux I might be using?

Both Red Hat Linux and SUSE Linux comply with the Linux Standards Base specifications for a standard Linux distribution. The differences are marginal. Surely you know your Linux platform, and you do have access to administration manuals for it. This book is not a Linux tutorial; it is a Samba tutorial. Let's keep the focus on the Samba part of the book; all the other bits are peripheral (but important) to creation of a total network solution.

What I find interesting is the attention reviewers give to Linux installation and to the look and feel of the desktop, but does that make for a great server? In this book, I have paid particular attention to the details of creating a whole solution framework. I have not tightened every nut and bolt, but I have touched on all the issues you need to be familiar with. Over the years many people have approached me wanting to know the details of exactly how to implement a DHCP and dynamic DNS server with Samba and WINS. In this chapter, it is plain to see what needs to be configured to provide transparent interoperability. Likewise for CUPS and Samba interoperation. These are key stumbling areas for many people.

At every critical junction, I have provided comparative guidance for both SUSE and Red Hat Linux. Both manufacturers have done a great job in furthering the cause of open source software. I favor neither and respect both. I like particular features of both products (companies also). No bias in presentation is intended. Oh, before I forget, I particularly like Debian Linux; that is my favorite playground.

| You did not use SWAT to configure Samba. Is there something wrong with it?

That is a good question. As it is, the `smb.conf` file configurations are presented in as direct a format as possible. Adding SWAT into the equation would have complicated matters. I sought simplicity of implementation. The fact is that I did use SWAT to create the files in the first place.

There are people in the Linux and open source community who feel that SWAT is dangerous and insecure. Many will not touch it with a barge-pole. By not introducing SWAT, I hope to have brought their interests on board. SWAT is well covered is TOSHARG2.

| You have exposed a well-used password not24get. Is that not irresponsible?
| Well, I had to use a password of some sort. At least this one has been consistently used throughout. I guess you can figure out that in a real deployment it would make sense to use a more secure and original password.
| The Idealx smbldap-tools create many domain group accounts that are not used. Is that a good thing?
| I took this up with Idealx and found them most willing to change that in the next version. Let's give Idealx some credit for the contribution they have made. I appreciate their work and, besides, it does no harm to create accounts that are not now used at some time Samba may well use them.
| Can I use LDAP just for Samba accounts and not for UNIX system accounts?

Yes, you can do that for user accounts only. Samba requires there to be a POSIX (UNIX) group account for every Windows domain group account. But if you put your users into the system password account, how do you plan to keep all domain controller system password files in sync? I think that having everything in LDAP makes a lot of sense for the UNIX administrator who is still learning the craft and is migrating from MS Windows.

| Why are the Windows domain RID portions not the same as the UNIX UID?

Samba uses a well-known public algorithm for assigning RIDs from UIDs and GIDs. This algorithm ought to ensure that there will be no clashes with well-known RIDs. Well-known RIDs have special significance to MS Windows clients. The automatic assignment used the calculation: RID = UID x 2 + 1000. Of course, Samba does permit you to override that to some extent. See the `smb.conf` man page entry for `algorithmic rid base`.

| Printer configuration examples all show printing to the HP port 9100. Does this mean that I must have HP printers for these solutions to work?
| No. You can use any type of printer and must use the interfacing protocol supported by the printer. Many networks use LPR/LPD print servers to which are attached PCL printers, inkjet printers, plotters, and so on. At home I use a USB-attached inkjet printer. Use the appropriate device URI (Universal Resource Interface) argument to the `lpadmin -v` option that is right for your printer.
| Is folder redirection dangerous? I've heard that you can lose your data that way.

The only loss of data I know of that involved folder redirection was caused by manual misuse of the redirection tool. The administrator redirected a folder to a network drive and said he wanted to migrate (move) the data over. Then he changed his mind, so he moved the folder back to the roaming profile. This time, he declined to move the data because he thought it was still in the local profile folder. That was not the case, so by declining to move the data back, he wiped out the data. You cannot hold the tool responsible for that. Caveat emptor still applies.

| Is it really necessary to set a local Group Policy to exclude the redirected folders from the roaming profile?
| Yes. If you do not do this, the data will still be copied from the network folder (share) to the local cached copy of the profile.

[11] There is an alternate method by which a default user profile can be added to the `NETLOGON` share. This facility in the Windows System tool permits profiles to be exported. The export target may be a particular user or group profile share point or else the `NETLOGON` share. In this case, the profile directory must be named `Default User`.

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