What is wd_v2.0_btld.img, the updated wd driver for SCO OpenServer 5.0.7? KEYWORDS: wd driver ide 137GB UDMA mode 6 atapi dvd cdrom 5.0.7 supplement cd 3 SATA S-ATA Serial ATA legacy write cache caching 2.0 RELEASE: SCO OpenServer System Release 5.0.7 PROBLEM: What is wd_v2.0_btld.img, the updated wd driver for SCO OpenServer 5.0.7? SOLUTION: The updated wd BTLD is available to download from: http://www.sco.com/support/update/download/osr507list.html and ftp://ftp.sco.com/pub/openserver5/507/drivers and provides the following new feature: The write cache of IDE drives can be enabled, improving the performance of drives shipped with the write cache disabled. What follows is the README for the WD BTLD. -------------------------------------------------------------------------- SCO OpenServer Updated wd Driver -------------------------------------------------------------------------- Contents * Overview * What's new in the updated wd driver * Before installing the wd driver * Installing the wd driver o Using the wd BTLD + Creating a BTLD disk + Installing the wd BTLD o Using the wd Driver * Configuring large IDE hard disks -------- Overview -------- The updated version of the wd(HW) driver included in Maintenance Pack 5 provides a number of bug fixes for SCO OpenServer Release 5.0.7 systems. Additionally, it adds these features: * Support for IDE hard disks that are larger than 137GB * Support for Serial ATA (S-ATA) controllers that operate in Legacy Mode. The wd driver supplied in the wd BTLD Version 2.0 provides this additional feature: * Support for control of the write caching behavior of IDE drives. The updated wd drivers are supported on the following platforms: * SCO OpenServer Release 5.0.7 plus Maintenance Pack 5 Because of software dependencies, it is important that the updated wd driver be installed using the sequence outlined here. Depending on your situation, you may already have completed some of these steps. 1. Install the SCO OpenServer operating system using either the Wd BTLD provided with MP5 or the Wd BTLD Version 2.0. The Version 2.0 driver is necessary in order to install in a reasonable amount of time on systems that are provided with IDE drives that have their write cache disabled. If the operating system is already installed, proceed to Step 2. 2. Install Maintenance Pack 5. This pack installs the MP5 wd driver and additional supporting files to the system, and is required even if you used a wd BTLD to install SCO OpenServer. 3. If the additonal feature provided by the driver in the wd BTLD Version 2.0 (write cache enable) is required, install it using btldinstall. See the btldinstall(ADM) manual page for more information. 4. Customers using hard disks larger than 137GB can now reconfigure the drive to make use of all drive space, and customers needing to configure the write caching behavior of IDE hard drives can do so. The latest wd BTLD and Maintenance Pack 5 for SCO OpenServer Release 5.0.7 are available at: http://www.sco.com/support/update/download/osr507list.html These steps are described in more detail later in this document. You should also read ``Before installing the wd driver'' prior to proceeding. ----------------------------------- What's new in the updated wd driver ----------------------------------- The updated wd driver in Maintenance Pack 5 (MP5) provides a number of bug fixes, including: * Divvy now correctly recommends a valid number of filesystems for disks greater than 14GB. (fz300644) * All compliant PCI IDE controllers now recognized. * UDMA mode 6 (UDMA 133) now supported. * Improved ATAPI device recognition. * ATAPI CD and DVD writer devices now supported. * More readable and useful debug output. To turn on debug output, use the wd.debug=[option] bootstring, where [option] can be any of the following: i for IDE controller identification u for Ultra DMA configuration g for disk geometry calculations * Better disk geometry configuration. * IDE hard disks larger than 137GB now recognized as having 137GB of space. Previously these drives were seen as smaller, possibly as small as 2GB. * When kernel debugger is enabled, driver no longer enters the debugger on certain unusual conditions. * Driver no longer panics when attempting to access a non-existent ATAPI device. * Driver no longer hangs during high levels of CD-Rom activity. (fz527519 / erg712269) * Driver now supports installation on an IDE disk located on the secondary IDE controller. (fz528226) * Full support for IDE hard disks that are larger than 137GB. * Support for SATA controllers that operate only in Legacy Mode or that can enable Legacy Mode in the BIOS. The wd driver in the wd BTLD Version 2 provides the above fixes, as well as this additional feature: * The write cache of IDE drives can be enabled, improving the performance * of drives shipped with the write cache disabled. ------------------------------- Before installing the wd driver ------------------------------- Before installing the wd driver: * Back up the data on your SCO OpenServer system and verify the integrity of the backup. * Ensure that you have a current, working emergency boot floppy disk set. * If you want to take advantage of the new support for IDE disks that are larger than 137GB, first read ``Configuring large IDE hard disks''. The wd(HW) manual page shipped with SCO OpenServer Release 5.0.7 systems is still current. ------------------------ Installing the wd driver ------------------------ The MP5 wd driver is available on the MP5 CD-ROM in two forms: Wd Boot-Time Loadable For use at boot-time when installing SCO Driver (BTLD) OpenServer. We recommend that you use the wd BTLD to install SCO OpenServer on IDE systems. Certain circumstances will require you to use the BTLD, including: * The FCS driver does not recognize system's IDE controller * The FCS driver does not support Ultra DMA on your system * The FCS driver incorrectly determines size of the hard disk during Initial System Load (ISL), which could lead to disk geometry conflicts after the installation is complete. You see the detected disk size during the Hard Disk Setup stage of ISL; the hard disk is not modified until this stage is complete so you can safely exit the installation at this point, if needed. (Note that disks larger than 137GB are limited in size to 137GB until MP5 is installed.) See ``Using the wd BTLD'' for instructions on installing the BTLD during SCO OpenServer installation. Maintenance Pack 5 Contains an updated wd driver, as well as additional supporting files. This supplement is required on all systems that want to use an updated wd driver, even if the system was installed with the wd BTLD. See ``Using the wd Driver'' for more information. The wd BTLD Version 2 driver is available at ftp://ftp.sco.com/pub/openserver5/507/drivers/wd_2.0 and is installed by mounting the BTLD filesystem and running btldinstall. See the btldinstall(ADM) manual page for more information. Using the wd BTLD ----------------- This section describes how to use the wd BTLD to perform an SCO OpenServer installation, including: * creating a BTLD disk * installing the wd BTLD If your system is already installed, you do not need to boot using the wd BTLD. You can install the MP5 wd driver by installing Maintenance Pack 5, or the latest wd driver by using btldinstall with the wd BTLD Version 2.0. See ``Using the wd Driver'' for more information. -------------------------------------------------------------------------- NOTE: Booting using the wd BTLD provides a minimum set of wd driver functionality to enable the installation of SCO OpenServer. Once system installation is complete, you must add Maintenance Pack 5 for the wd driver to work correctly. -------------------------------------------------------------------------- To boot use any version of the wd BTLD: 1. Log in as root. 2. Download the wd BTLD image, from either the SCO web site or using FTP, to a temporary directory (such as /tmp/wd_btld.img) on your machine: + to use the SCO web site, go to the SCO Update Service and Supplemental Downloads web page for SCO OpenServer Release 5.0.7: http://www.sco.com/support/update/download/osr507list.html + to use FTP, go to the SCO Support Download Area: ftp://ftp.sco.com/pub/openserver5/507/drivers/wd_2.0 3. Format a 3.5-inch high-density floppy disk using the format(C) command. 4. Copy the wd_v2.0_btld.img image to the floppy disk using the dd(C) command: dd if=/tmp/wd_v2.0_btld.img of=/dev/fd0 bs=18k 5. Verify that the image was both downloaded and written to the floppy disk correctly using the sum(C) command: sum -r /tmp/wd_v2.0_btld.img sum -r /dev/fd0 The latter command should return: 35198 2880 /dev/fd0 If the checksum matches the above, the floppy disk is ready for use. 6. Insert the SCO OpenServer Primary Boot Disk (either CD-ROM or floppy disk) into the drive on the system that you want to install and turn on the computer. (This step assumes that the IDE controller is already installed in the computer.) 7. At the boot prompt, enter 'link'. 8. When prompted for the packages that you want linked in to the system, enter the driver name 'wd'. 9. When prompted for the driver volume, insert the wd BTLD floppy disk that you created and press . 10. The link(HW) command prompts you to replace the current driver with the new wd driver. Type 'r' at the prompt and press . 11. After the wd driver is successfully installed, you are prompted to re-insert your boot disk. You can now continue with the SCO OpenServer installation. 12. After SCO OpenServer is installed, install Maintenance Pack 5. MP5 and its installation instructions can be obtained at http://www.sco.com/support/update/download/osr507list.html 13. If the additional feature provided by the driver in the wd BTLD Version 2 (write cache enable) is required, install it on top of MP5 by using btldinstall. See the btldinstall(ADM) manual page for more information. Using the wd Driver ------------------- Maintenance Pack 5 installs an updated wd driver, as well as a number of supporting files that are required for the driver to work correctly. You must install this supplement to use an updated wd driver, even if you used a wd BTLD to install the system. To install Maintenance Pack 5, see the instructions in the MP5 Release Notes, available from http://www.sco.com/support/update/download/osr507list.html -------------------------------- Configuring large IDE hard disks -------------------------------- IDE hard disks that are larger than 137GB are supported on SCO OpenServer Release 5.0.7 systems that include Maintenance Pack 5. Once all of the required software is installed, you will need to reconfigure the hard disk so that all of the drive's space is available. * When using the updated wd driver to install SCO OpenServer on an IDE hard disk that is larger than 137GB, the partition is initially limited to 137GB. Once SCO OpenServer Release 5.0.7 Maintenance Pack 5 is installed, the drive areas above 137GB become available. At this point, you need to add additional partitions or expand existing partitions to make use of the entire hard disk. * Similarly, if SCO OpenServer is already installed on an IDE hard disk that is larger than 137GB, adding SCO OpenServer Release 5.0.7 Maintenance Pack 5 with the updated wd driver enables the system to recognize the full capacity of the drive, but the hard disk must be reconfigured to make use of the newly available space. ---------------------------------------------------------------------- NOTE: To add a new larger-than-137GB IDE hard disk to an existing SCO OpenServer system, install SCO OpenServer Release 5.0.7 Maintenance Pack 5 with the updated wd driver before adding the new disk. This will ensure that you can access the entirety of the hard disk immediately without additional intervention. ---------------------------------------------------------------------- There are a few options for reconfiguring your hard disk to make use of the drive space above 137GB. -------------------------------------------------------------------------- NOTE: All of these options involve the use of fdisk(ADM) and divvy(ADM). These are powerful tools that should be used with caution to ensure that you do not accidentally lose data. Before using these commands: * Back up the data on your SCO OpenServer system and verify the integrity of the backup. * Ensure that you have a current, working emergency boot floppy disk set. -------------------------------------------------------------------------- * Run fdisk(ADM). The utility reports a larger number of tracks than before, some of which are unallocated. -------------------------------------------------------------- NOTE: When performing any of the steps described below, fdisk may warn that your new UNIX partition is not on a cylinder boundary. You can safely ignore this message. -------------------------------------------------------------- o If your disk contains only one partition, which is of the type UNIX and starts on track 1, select fdisk option ``2. Use Entire Disk for UNIX''. The partition is expanded to the end of the disk; the contents of the partition are preserved. o If your disk contains a single UNIX partition that starts on a track other than 1, or contains multiple partitions where the last entry in the partition table is a UNIX partition, you can delete that partition (select option ``6. Delete Partition'') and then recreate it (select option ``4. Create UNIX Partition''), making it larger. You will not lose any data provided the new partition starts on the same track number as the deleted partition. ----------------------------------------------------------------- WARNING: Before attempting this, write down the starting track number of the partition you will delete. This number is extremely important and the fdisk utility will scroll this information off the screen before you need it again. Once you delete the partition, do not exit fdisk until you have recreated the replacement partition, or you will lose all data that existed in the deleted partition. ----------------------------------------------------------------- o If the last disk partition is any type other than UNIX, you must add a new UNIX partition to allocate the unused tracks on the disk. Select fdisk option ``3. Use Rest of Disk for UNIX''. This option preserves all existing partitions. * Once you have expanded existing partitions and/or added additional partitions, run divvy(ADM) to create new divisions and filesystems. ----------------------------------- Configuring IDE drive write caching ----------------------------------- In the wd BTLD Version 2, support has been added to report and control the write caching behavior of IDE hard drives. This is provided because, while IDE hard drives can be configured to either cache writes or do direct writing without caching, there is generally no means provided through the BIOS or other facilities to make such a change. Most drives are shipped with write caching enabled, because it provides a very large performance enhancement. However, it also increases the chance of data loss should the system lose power unexpectedly, so some system vendors ship drives with the write cache turned off. The driver in this version of the wd BTLD will check the status of the write cache at boot time, and for any drive that does not have write caching enabled, will report: NOTICE: wd %d/%d (unit %d): write cache is not enabled Also, at install time, if the drive that is being installed on does not have write caching enabled, it will be enabled for the duration of the install in order to allow the install to complete in a reasonable amount of time. To allow the write cache to be forced on, there is a new variable in the file /etc/conf/pack.d/wd/space.c, "wdEnableWriteCache". By default this is set to 0, and in this state it has no effect. If it is set to 1 (and the kernel is relinked and the system rebooted), all IDE drives that have disabled caches will have their caches enabled at boot time. If the system is shut down normally, any drives that had write caching turned on by this means will have it turned off again. SEE ALSO: the ``Adding hard disks'' chapter in the SCO OpenServer Handbook and the fdisk(ADM) and divvy(ADM) manual pages for more information on performing any of these steps.