Check Disk:
FortiMail-100:
diagnose sys smartctl ata /dev/hdc
FortiMail-400:
diagnose sys smartctl ata /dev/hda diagnose sys smartctl ata /dev/hdb
FortiMail-400B:
diagnose system smartctl ata /dev/sda diagnose system smartctl ata /dev/sdb
FortiMail-2000A:
diag system smartctl 3ware,<hard-drive_int> /dev/twa0
FortiMail-4000A:
diag system smartctl 3ware, <hard-drive_int>/dev/twa0
2000B, 3000C:
diagnose system smartctl megaraid,[0-5] /dev/sda