I'm trying to ensure that the revert process is as reliable as possible in our lab manager environments. We frequently (daily) revert a 10-12 server workspace to a previous version, upgrade it, test on it. Every few weeks, I hit a new problem after a revert, and a team or two has to wait while I monkey around.
The servers are Win2K3 servers running various applications. They are members of an domain, external to the workspace.
Question: What do you do to achieve 100% reliable revert? Any suprises in store for me, beyond the following? Better resolutions to these problems?
Note: Unfortunately, fenced workspaces are not practical in this scenario. These are unfenced environments. Saving the workspace to a to configuration and cloning tends to be far too slow for daily use - even though we've made disks as small as practical (10GB per machine).
Snags hit:
Machine changes password (?) or some other credentials with DC every x weeks. The snapshot can't connect to domain. Prevent by
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters] "DisablePasswordChange"=dword:00000001
Computers revert from snapshot with incorrect times, times out of sync between machines. Chaos ensues. Final resolution: Make sure host is running NTP client - one of ours was not, ensure clients sync to host. Per VMWare, that was the root of many of our problems.
Summary good answers
- Take snapshot with power off. Prevents a variety of problems, including NTP.