During the last 9 days three caching nodes went down with the same symptoms:
* Nothing on the SEL
* KVM unresponsive
* Network down
* Nothing on the logs
A power cycle fixed them.
So far the affected systems are PowerEdge `R440`:
* cp3053 - T239041
* cp1077 - T238289
* cp3057 - T237348 T239502
* cp3065 - T238032
* db2125 - T239042 Kernel at the time of the crash: `Linux db2125 4.9.0-11-amd64 #1 SMP Debian 4.9.189-3+deb9u1 (2019-09-20) x86_64 GNU/Linux`
* cp3063 - T239310
* cp1087 - T239449
* cp3055 - T240425 (twice, same task, I think the firmware has not yet been updated)
* backup2001 - T240177 T237730 (the second crash happened with the firmware running the latest version)
* cp3051 - T241306
* cp3061
Maybe a kernel upgrade or a CPU microcode update is messing with them?