"mkvg" Failure During a Full System Reinstall

This document provides a workaround for a failed mkvg command. It applies to AIX Versions 4.1 and 4.2, and Sysback.obj 3.3.3.

When trying to reinstall rootvg from a Sysback full system backup tape in AIX Version 4.1.5 and 4.2.1 using Sysback Version 3, the following error message appears:

    mkvg command failed in creating rootvg volume group 

This is a known defect found with Sysback Version 3. It has been corrected in Sysback Version 3.3.3.17.

Changes made to the mkvg script causes the error. The mkvg now needs the use of the /usr/bin/dd command; however, Sysback is removing the /usr/bin/dd command before starting the install process. This causes the mkvg command to fail.

Workaround one

1. Reboot the system into service mode again from the Sysback tape.
2. Choose option 4, Start a limited function MAINTENANCE shell, from the Sysback main menu.
3. Execute the following command:

       cp /usr/bin/dd /usr/bin/dd.bak 
   

4. Exit.

Start the install again. At this point, the mkvg will fail again. From the Sysback main menu choose the option to Perform System Maintenance and execute the following commands:

1. cp /usr/bin/dd.bak /usr/bin/dd
2. mkvg -fy rootvg -s <pp size> <hdisk# hdisk#>

   Include all of the hdisks that should be part of rootvg. The pp size depends on the size of the disks. If all of the disks are under 4GB in size, the pp size will be 4; if one disk is between 4GB and 8GB in size, the pp size will be 8; and if one disk is above 8GB, the pp size will be 16.

3. Exit.

The install should now continue.

Workaround two

This method is used if there is a second system running AIX 4.2 or 4.1.5 with a diskette drive.

On the second system that is up and running, follow these steps:

1. Put a diskette in the drive.
2. Execute the following command:

       find  /usr/bin/dd | backup -ivq 
   

   NOTE: After this step, remove the diskette from the drive.

3. Choose the option to Perform System Maintenance from the Sysback main menu and put the diskette back in the drive.
4. Execute the following command:

       restbyname -xvq 
   

5. Execute the following command:

       mkvg -fy rootvg -s <pp size> <hdisk# hdisk#> 
   

   Include all of the hdisks that should be part of rootvg. As in the previous workaround, the pp size depends on the size of the disks. If all of the disks are under 4GB in size, the pp size will be 4; if one disk is between 4GB and 8GB in size, the pp size will be 8; and if one disk is above 8GB, the pp size will be 16.

6. Exit.

The install should now continue.

This fix will allow the user to correct the defect in the Sysback Version 3 code.

Execute the following commands:

    cd /usr/lpp/sysback/inst 
    cp sysmain sysmain.bak 

Using a favorite editor, go into the sysmain file.

Change these lines

if [ $BOOTTYPE != $NET ] 
   then rm -f /usr/lpp/sysback/inst/sysmenus \ 
                /usr/lpp/sysback/inst/sysgetvginfo \ 
                /usr/lpp/sysback/inst/syscheckvginfo \ 
                /usr/lpp/sysback/inst/syseditvginfo \ 
                /usr/sbin/logredo /usr/sbin/getrootfs \ 
                /usr/sbin/importvg /usr/sbin/fsck \ 
                /usr/lib/methods/devices.cat /bin/dd 
fi 

if [ $BOOTTYPE != $NET ] 
   then rm -f /usr/lpp/sysback/inst/sysmenus \ 
                /usr/lpp/sysback/inst/sysgetvginfo \ 
                /usr/lpp/sysback/inst/syscheckvginfo \ 
                /usr/lpp/sysback/inst/syseditvginfo \ 
                /usr/sbin/logredo /usr/sbin/getrootfs \ 
                /usr/sbin/importvg /usr/sbin/fsck \ 
                /usr/lib/methods/devices.cat 
fi 

NOTE: At the end of the last line remove /bin/dd.

Save the file.

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