Or, “Lessons Learned from Today’s Migration.”
We migrated our production database cluster from an MSA 1000 to an EVA 8100 with new servers this morning. (This is much easier than in-place upgrades where you take down the system, wipe the cluster nodes and rebuild them on the spot if you can swing it.) It went fairly smoothly, though when I went to compare the amount of time the EVA took to make full backups of all the databases (8 minutes) to the time it took the MSA (21 minutes), I found that even though I’d restored msdb from the previous server, there was no job history. Apparently SQL Agent doesn’t take kindly to foreign job history and zorched it as soon as the new server ran its first job. I restored a copy of msdb, shut down SQL Agent and sucked the contents of sysjobhistory back in from the copy, changing the server column to the new server’s name (and having to bump up the value of instance_id since the new server’s SQL Agent had already made a few records), and the transplant took.