I was wondering how your back-out plans look like. Untill now I must admit I never have had a really decent back-out plan in place when installing cumulative updates. I did ran into some issues sometimes, but usually those were fixable in a small amount of time inside of the outage window. But I would not have a good solution when the shit really hits the fan.
Theoretically speaking, would this suffice:
– Restore pre-upgrade SQL back-ups of all databases
– Restore pre-upgrade VM images of front-ends and back-ends
I cannot find a reason why it wouldn’t, but since I haven’t tried….
We’re also running DocAve back-ups at the customer I’m at; but do those also revent SharePoint binaries? I assume they don’t.
Shutting down the VMs, including SQL for consistency, and taking an image would be supported as the farm is in a consistent state. Â Otherwise, a full farm backup would be called for. Â In the event that it really didn’t work and calling PSS on a Sev A wasn’t an option, rebuilding the farm and restoring the backup would be the method to take.
Of course we are testing every update in a pre-production farm (two actually) as well. But that’s never a 100% guarantee as you also state. Up to know, I never had any real problems. But suppose you’ve installed the update and things really go bad. What then?
You mention restoring the farm from a pre-upgrade back-up: how? When snapshots / live back-ups are not supported; what is? Shutting them farm down and then creating back-up images of the servers?
The SharePoint Object Model for backup does not cover the SharePoint binaries themselves. Â You would need to restore the entire farm from a pre-upgrade backup in order to ‘back out’ of the specific CU. Â I would never recommend this — instead, make sure to do full test passes on a pre-production farm that is configured as close to the production farm as possible. Â You won’t weed out every issue, but you may catch business critical issues. Â Do keep in mind that snapshotting or taking live bacukps SharePoint VMs is not supported.
