20 plus years in IT and I will be getting my first write up today

Posted by Frankaintmyfriend@reddit | sysadmin | View on Reddit | 739 comments

Been in every aspect of IT over the yaers. I have always had great reviews and never been written up...until today.

Yesterday I was migrating VM's from one datastore to a new one in vSphere. It was during the day, but it was a simple vmotion migrate, so no downtime. While I was migrating, I was cleaning up old datastores and getting rid of them. Not sure what happened, but I looked in one datastore that contains swapfiles and it showed no VM's, so I unmounted it (as I had done other datastores earlier in the day). Unfortunatly, I didn't see the files in the fiels section that contained the vswap files of the VM's I hadn't migrated yet. Unmounting the datastore caused a memory issue and sent the host cluster into HA recovery mode, rebooting nearly every VM! Total downtime was less than 10 minutes, but it took down the phone systems and other critical servers in the middle of the day.

Havn't gotten the write up yet, but I am almost positive it's coming.

So, lessons learned and a warning to others, don't unmount swap file datastores during a migration.