Patch rollback

[Craig A. Sharp]

I will be patching one of our servers tomorrow. What is the proper way to do a patch rollback if there is an issue?

[Steven E. Protter]

Shalom Craig,

If its one patch, the backout is swremove PHSS_12345

Just use a real name.

If its a complex patch set, you would need to issue on one command line an swremove statement that includes everything you installed.

Usually I do a make_tape_recovery or make_net_recvery right before patching.

I include only vg00 and restore the system if it refused to boot or does something unacceptable after patching.

SEP

[Jeff Schussele]

Hi Craig,

FIRST - do *not* run any cleanup commands to commit superseded patches.

Then I would probably do it one of two ways.

1) make a "safe" copy of /stand/vmunix.prev -- Just in case
2) swremove the bundle(s) you just swinstalled.
3) Reboot - If the new vmunix is "bad" boot the safe copy of vmunix.prev - do not boot the "current" vmunix.prev

OR

1) Reboot & boot vmunix.prev - then make a safe copy of it
2) swremove the bundle(s) you swinstalled
3) Reboot - If the new vmunix is "bad" boot the safe copy of vmunix.prev - do not boot the "current" vmunix.prev

Either way should get it done.

HTH,
Jeff

[James R. Ferguson]

Hi Craig:

For an individual patch, 'swremove' will roll-back the patch assuming that you have the requisite roll-back information in '/var/adm/sw'. That is, you didn't install the new patch with '-x patch_save_files=false'.

I actually prefer to begin a major patch session by makeing an Ignite 'make_recovery_tape' and then commiting all patches to form a baseline:

# swmodify -x patch_commit=true \*

This gives a clean base upon which to install new patches.

Rolling-back patches shouldn't be taken lightly since there may be dependent relationships among patches.

Regards!

...JRF...

[Craig A. Sharp]

We are all set...thanks to all!