Server was down... what happened
Around 9:40 PM EST tonight (Jan 8) I performed a server reboot from which the server did not, for some reason, recover. At about 10:45 a hard reboot was done by the datacenter.
Then, at about 11:10 the server went down again for about 20 minutes. This was actually a good thing - it was for a hardware upgrade. We are now running on twice as much RAM as before - so hopefully we'll have fewer problems in the future.