On our 2012 server that runs VM's we perform a backup three times a week as well as replicating the VM's to another server. Most of the time this works fine. But once in a while (a few times in the last month) it doesn't. <o:p></o:p>
A couple weeks ago in the middle of the night there was a power outage that caused the servers to restart. This didn't impact or organization at all, but it happened in the middle of a backup. That backup failed. The next scheduled backup failed because it thought another backup operation was running (there wasn't). I manually started a backup and that worked fine, except it took about three times as long to run and it removed all previous backups from the backup drive. Our backups ran fine for the next couple weeks until one randomly took about three times as long as a normal one and also removed all previous backups. <o:p></o:p>
There were no errors in the event viewer for those backups. The backup drive is never more than half full. It always has at least a TB of free space for a backup file that is about 600-800 GB. It normally saves weeks to months of old backups. My wbadmin command is below. <o:p></o:p>
START BACKUP -backupTarget:H: -allCritical -systemState -quiet
Thanks for the help.