Over the holiday weekend, one of our clients experienced a power outage. When everything came back online, most devices seemed to be fine, but a few (one of our ESXi hosts and a number of VDIs) could not get a proper IP address. They were getting the 169 APIPA from Windows. I looked at the DHCP logs and from the time that the power outage occurred, there had been 0 leases or renewals. It was like DHCP was just idle the entire weekend.
I bounced it and all of the sudden, all the leases started pouring in and everything that was getting APIPA got a normal address and everything went back to normal.
My question is: Is there some sort of setting with DHCP that's causing it to act like this? I feel like a hard outage shouldn't break DHCP, especially if it's getting a fresh reboot.
I'd like to figure out what happened so that if another outage occurs, we don't run into the same issues.
Log timeline:
11/25 11:15 PM, server started after outage:
00,11/25/20,23:12:23,Started,,,,,0,6,,,,,,,,,0
64,11/25/20,23:12:23,No static IP address bound to DHCP server,,,,,0,6,,,,,,,,,0
around an hour later, devices start losing their addresses:
24,11/26/20,00:00:19,Database Cleanup Begin,,,,,0,6,,,,,,,,,0
18,11/26/20,00:00:19,Expired,10.x.x.16,,,,0,6,,,,,,,,,0
18,11/26/20,00:00:19,Expired,10.x.x.18,,,,0,6,,,,,,,,,0
18,11/26/20,00:00:19,Expired,10.x.x.19,,,,0,6,,,,,,,,,0
etc...
A couple hours after that, the entries start being deleted
24,11/26/20,03:12:24,Database Cleanup Begin,,,,,0,6,,,,,,,,,0
16,11/26/20,03:12:24,Deleted,10.x.x.16,,,,0,6,,,,,,,,,0
16,11/26/20,03:12:24,Deleted,10.x.x.18,,,,0,6,,,,,,,,,0
16,11/26/20,03:12:24,Deleted,10.x.x.19,,,,0,6,,,,,,,,,0
etc...
After that, no activity at all outside of database cleanup:
24,11/26/20,21:12:29,Database Cleanup Begin,,,,,0,6,,,,,,,,,0
25,11/26/20,21:12:29,0 leases expired and 0 leases deleted,,,,,0,6,,,,,,,,,0
25,11/26/20,21:12:29,0 leases expired and 0 leases deleted,,,,,0,6,,,,,,,,,0
24,11/26/20,22:12:29,Database Cleanup Begin,,,,,0,6,,,,,,,,,0
etc... (until reboot)
Today, when I rebooted, everything started getting addresses again
01,11/30/20,05:17:21,Stopped,,,,,0,6,,,,,,,,,0
00,11/30/20,05:17:26,Started,,,,,0,6,,,,,,,,,0
55,11/30/20,05:17:26,Authorized(servicing),,<redacted>.net,,,0,6,,,,,,,,,0
10,11/30/20,05:17:26,Assign,10.x.x.16,<redacted>
10,11/30/20,05:17:26,Assign,10.x.x.18,<redacted>
10,11/30/20,05:17:26,Assign,10.x.x.74,<redacted>
etc...