Server Froze overnight

[mostlydave]

overnight my server froze for the first time ever. This morning I could ping and connect with ssh, but the web interface would not load. I was able to get to unmenu for a little while and tired ot take the array offline but that failed. I ended up doing a hard reboot, and it's doing a parity check now.

 

Is there any way to see what caused the freeze up now that it's rebooted, and if I can connect with putty if it freezed up again can I initiate a clean shutdown with commands?

[dgaschk]

See console commands in my sig.