TECHNICAL INFORMATION DOCUMENT

TITLE:              PTF631 - Bad Block Recovery for IDE Drives
DOCUMENT ID:        TID300150
DOCUMENT REVISION:  B
DATE:               25JAN95
ALERT STATUS:       Yellow
INFORMATION TYPE:   Symptom Solution
README FOR:         PTF631

PRODUCT and VERSION:
UnixWare 1.1

ABSTRACT:

This file contains PTF631 - Bad Block Recovery for IDE Drives.  
tries to remap a block when not necessary with IDE controllers. This 
patch is for UnixWare 1.1, UnixWare 1.1.1, UnixWare 1.1.2.


SYMPTOM

Sometimes the athd driver attempts to remap a block which the driver 
deems to be bad when in fact the hard disk is fine.  The symptom appears 
in some IDE controllers.  It appears that not all combinations of IDE 
controllers and hard disks behave exactly the same way.  The result is 
that the controller goes off line, and athd sees this as a bad block, 
tries to remap it, and fails.

SOLUTION

Apply the ptf631 file.

Installation Instructions:

DATATYPE: datastream

1.  Download the ptf631.Z and ptf631.txt files to the /tmp directory
    on your machine.

2.  Read the release notes contained in this file and follow the
    instuctions to add the packages to your system.

3.  Now become root, uncompress the file and add the package to your 
    system using the following commands:

        $ su
        # uncompress /tmp/ptf631.Z
        # pkgadd -d /tmp/ptf631 ptf631

Solution Specifics

GENERAL DESCRIPTION
-------------------
PTF631 provides a new athd driver for UnixWare 1.1. The IDE/ESDI HBA 
driver (athd(7)) supports more thorough error recovery to recover 
from transient read failures.  The new athd driver resolves a problem 
where the driver would occassionally fail with IDE controllers.
symptom is an attempt to remap the block which the driver deems to be 
bad when in fact the hard disk is fine.pears with some combinations 
of IDE controllers and hard disks.  The result is that the controller 
goes off line.  hd driver then sees this as a bad block and tries 
to remap it (and fails).


HARDWARE NOTES AND RECOMMENDATIONS
----------------------------------

This PTF is applicable for the i386, i486 and Pentium architectures.

SOFTWARE NOTES AND RECOMMENDATIONS
----------------------------------

PTF631 is available on a single floppy diskette in pkgadd format.  The PTF
updates three files:

          /usr/include/sys/athd.h
          /etc/conf/pack.d/athd/Driver.o
          /etc/conf/pack.d/dcd/Driver.o

After the package is installed, the system should be rebooted, during which
time the Unix operating system kernel will be rebuilt to reflect the driver
changes.

INSTALLATION INSTRUCTIONS
-------------------------

To install this package on your computer, you need to do a 'pkgadd' of the
diskette.  You should be logged in as root when installing this package.

After inserting the diskette into the first floppy drive, enter the following
command:

# pkgadd -d diskette1

You will then be prompted on how to continue the installation.

Note : If you are working from the desktop, you can do the installation by
selecting the "System_setup" icon from the root window, followed by
"Appln_setup". Then, click on "View", select "Uninstalled_apps" and select the
floppy diskette.  You must be logged in as the system owner.

After the installation completes, you must rebuild the Unix operating system
and reboot the machine for the changes to take effect.  This can be
accomplished by typing the command:

          # init 0