It is a Dell Poweredge 2650 with three internal scsi disks configured as RAID-5. All disk indicators are green.
smartctl -a produces this output:
[root@server ~]# smartctl -a /dev/sda
smartctl version 5.33 [i686-redhat-linux-gnu] Copyright (C) 2002-4 Bruce Allen
Home page is
http://smartmontools.sourceforge.net/Device: DELL Virtual Disk 0 Version: V1.0
scsiModePageOffset: response length too short, resp_len=4 offset=4 bd_len=0
>> Terminate command early due to bad response to IEC mode page
A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options.
The '-T permissive' switch doesn't make it better...