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How to determine the status of a RAID
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The status of a RAID can be determined by a number of utilities. A hardware-based RAID usually comes with a
RAID configuration utility that is either
a Windows application or implemented in the RAID controller BIOS. In the latter case, the user needs to press special key sequences at boot time to invoke the
RAID controller BIOS. Other useful utilities include the Disk Manager and Windows Explorer.
RAID configuration utility
A RAID configuration utility displays the hardware state of a RAID, which can be:
- Active or online.
- Degraded: One disk in a RAID 5 has failed. The RAID is still functioning thanks to parity information on the remaining disks that can be used to
regenerate the data on the missing disk. However, this causes slower performance. Moreover, should a second disk fail, data would be
lost.
- Inactive, offline or undefined: RAID is not working or no RAID is defined.
The exact display and wording vary among RAID controllers.
Disk Manager
Disk Manager is a built-in Windows utility to manage disks and volumes including software-based RAID
volumes. On Windows XP, it can be started
by clicking Start, Control Panel, Administrative Tools, Computer Management, Disk Management.
For a hardware-based RAID, the Disk Manager can be used to determine if the RAID is working.
A working RAID should be displayed as a single disk.
Disk Manager (and Windows) cannot access the individual member disks comprising the RAID. The RAID controller manages them and presents
a single logical disk to Windows. If the RAID is not displayed or the individual member disks are displayed, the RAID mechanism is
not functioning.
Disk Manager can be used to create, change or delete a software-based
RAID 0 (striped volume)
or RAID 5.
Windows Explorer
Windows Explorer or "My Computer" can be used to determine if a volume is accessible and if files are missing.
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