We've been seeing a greatly increased number of 2213's over the last month. Fixing them each time isn't an issue, but I haven't been able to find a root cause of why it keeps happening in the first place. It's not limited just to one or two servers, either, and while some may happen after scheduled reboots, others happen in the middle of the day, outside of regular backup hours. Some are on physical servers, and some are on VM's.
Does anyone have any troubleshooting ideas, or a list of all known causes of unexpected shutdowns? Something, anything I can use to try to track the causes down?