[CentOS] Server locking up everyday around 3:30 AM - (INFO: task wget:13608 blocked for more than 120 seconds) need sleep, help.

Sat Mar 12 08:07:57 UTC 2011
Alexander Georgiev <alexander.georgiev at gmail.com>

>
> Almost everyday around 3:30 AM the server completely locks up and has
> to be power cycled before it will come back online.
> (this means someone hat to wake up and reboot the server, oh how I
> love being an internet janitor! :)
>
> Smells like a hardware issue to me too, but I went through all of the
> dell diagnostics, updated the firmware, everything checks out as being
> okay, RAID, disks, RAM, etc... Spent an hour on the phone with a Dell
> tech. No hardware issues, at least that we were able to find.
>
> There are no cron jobs that run at 3:30, no backups, the server has a
> load of 0, nothing is scheduled around that time...

do you have smartd set to run short/long hard disk checks during the
night? it is done via /etc/smartd.conf, not via cron.