[CentOS] System hanged - no info in logs.

Thu Apr 12 15:24:33 UTC 2012
John Doe <jdmls at yahoo.com>

From: Rafał Radecki <radecki.rafal at gmail.com>

>T he system was not rebooted, it just was not responsive (ssh) and has a gap
> in logfiles for 15 minutes. After 15 minutes it started responding.

Maybe also check the bios/ipmi logs...