[CentOS] system unresponsive

Wed May 22 13:29:36 UTC 2019
mark <m.roth at 5-cent.us>

Ok, we used to get this occasionally on cluster nodes, and we just got it
on a fileserver (very bad). The system is discovered to be unresponsive:
it doesn't ping, and plugging a console in, you can see that it's not
dead, but there nothing at all on the screen, nor does it respond to even
<ctrl-alt-del>. The only answer is to power cycle it; it comes up fine.

Nothing in /var/log/dmesg or /var/log/messages. No abrts I can find. sar
tells me it went unredponsive between 18:10 and 10:20 yesterday. Note that
there are no further entries in sar, either, for yesterday, after the
event, and nothing till I power cycled it.

Has anyone else seen this - I can't imagine it's only us - or have any

C 7, 7.6.1810