VXVM 4.0 : Recover Root Mirror from Backup

The procedure needs an additional step in step 9 to remove /a/dev/vx/dsk/bootdg and /a/dev/vx/rdsk/bootdg.

Full procedure in the Troubleshooting Guide should be:
1. boot cdrom -s

2. Use format to create partitions

3. Use newfs or mkfs to create filesystems for partitions created in step 2.

4. mount root slice to /a

5. restore root filesystem

6. Use the installboot command to install a bootblock device on /a

7. Mount other filesystems needing to be restored

    # mount /dev/dsk/c0t0d0s5 /a/usr

8. Restore other filesystems

9. Disable startup of VxVM by modifying files in the restored root file system
as follows:
a. touch /a/etc/vx/reconfig.d/state.d/install-db

b. Copy /a/etc/system to a backup file such as /a/etc/system.old

c. Comment out the following lines from /a/etc/system by putting a * character in front of them:

        set vxio:vol_rootdev_is_volume=1
rootdev:/pseudo/vxio@0:0
        These lines should then read:
        * set vxio:vol_rootdev_is_volume=1
* rootdev:/pseudo/vxio@0:0

d. Copy /a/etc/vfstab to a backup file such as /a/etc/vfstab.old.

e. Edit /a/etc/vfstab, and replace the volume device names (beginning with /dev/vx/dsk) for the / and /usr file system entries with their standard disk devices, /dev/dsk/c0t0d0s0 and /dev/dsk/c0t0d0s6. For example, replace the following lines:

        /dev/vx/dsk/rootvol /dev/vx/rdsk/rootvol / ufs 1 no -
/dev/vx/dsk/usrvol /dev/vx/rdsk/usrvol /usr ufs 1 yes -

with this line:

        /dev/dsk/c0t0d0s0 /dev/rdsk/c0t0d0s0 / ufs 1 no -
/dev/dsk/c0t0d0t6 /dev/rdsk/c0t0d0s6 /usr ufs 1 yes -

f. Remove entries from /dev/vx/dsk/bootdg and /dev/vx/rdsk/bootdg directories.

  1. rm /a/dev/vx/dsk/bootdg/* <—- New
  2. rm /a/dev/vx/rdsk/bootdg/* <— New

10. Shut down the system cleanly using the init 0 command, and reboot from the new root disk. The system comes up thinking that VxVM is not installed.

11. If there are other disks in the old boot disk group that are not used as root disk mirrors, follow these steps to bring in the old boot disk group (minus the boot disk which VxVM will think has failed) and set up the new boot disk (if no other disks were in the old boot disk group, then skip and use step 12):

a. Remove files involved with the installation that are no longer needed:

      # rm -r /etc/vx/reconfig.d/state.d/install-db

b. Start the VERITAS Volume Manager I/O daemons:

      # vxiod set 10

c. Start the VERITAS Volume Manager configuration daemon in disabled mode:

      # vxconfigd -m disable

d. Initialize the volboot file:

      # vxdctl init

e. Enable vxconfigd:

      # vxdctl enable

Steps a through e enable the old boot disk group excluding the root disk which VxVM interprets as failed.

f. Use the vxedit command (or the VERITAS Enterprise Administrator (VEA)) to remove the old root disk volumes and the root disk itself from VERITAS Volume Manager control.

g. Use the vxdiskadm command to encapsulate the new root disk and initialize any disks that are to serve as root disk mirrors. After the required reboot, mirror the root disk onto the root disk mirrors.

12. If there are only root disk mirrors in the old boot disk group (use only if step 11 was skipped):

a. Run the vxinstall command

b. Run vxdiskadm command to encapsulate the root disk

c. After the required reboot, mirror the root disk onto the root disk mirrors.

Ramdev

Ramdev

I have started unixadminschool.com ( aka gurkulindia.com) in 2009 as my own personal reference blog, and later sometime i have realized that my leanings might be helpful for other unixadmins if I manage my knowledge-base in more user friendly format. And the result is today's' unixadminschool.com. You can connect me at - https://www.linkedin.com/in/unixadminschool/

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