Hardware manual

Group Administration Group monitoring
15–23
Warning: A disk drive failure in a RAID 5 or RAID 10 set that is degraded might result in data loss.
When a drive in a RAID set fails, a member behaves as follows:
• If a spare
disk drive is available: Data from the failed drive is reconstructed on the spare. During the
reconstruction, the RAID set that contains the failed drive is temporarily degraded.
• If a spare
disk drive is not available, and the RAID set has not reached the maximum number of drive
failures: The RAID set that contains the failed drive is degraded. For RAID 5, RAID 50, or RAID 6,
performance might decrease.
• If a spar
e
disk drive is not available, and the RAID set has reached the maximum number of drive
failures: The member is set offline, and any volumes and snapshots that have data stored on the member are
set offline. Data might be lost and must be recovered from a backup or replica.
When you replace a failed disk, a
member behaves as follows:
• If a spare disk drive
was used: The new drive automatically becomes a spare, with no effect on performance.
• If a RAID
set was degraded: Data is automatically reconstructed on the new drive and performance goes
back to normal after reconstruction.
• If a member was offline because of multiple RAID set drive failures: Any volumes
snapshots with data on
the member are set offline and data might be lost.
In some cases, a member might detect a problem with a disk
drive. The member automatically copies the data on
the failing disk drive to a spare disk drive, with no impact on availability and little impact on performance. The
group generates event messages informing you of the progress of the copy-to-spare operation. I/O is written to both
drives until the copy-to-spare operation completes. If the disk drive completely fails during the operation, data is
reconstructed on the spare using parity data, as usual.
Replace any failed disks immediately. For information about replacing dis
k
drives, see the Hardware Maintenance
manual for your array model or contact your PS Series support provider.
Monitoring network hardware
A member must have at least one functioning network interface connected to a network and configured with an IP
address. Each control module has multiple Ethernet ports.
If you experience network problems, group members might lose the ability to communicate with each
other over
the network. In such a group, some management operations are not allowed. For example, you cannot change the
IP addresses of an isolated member.
If the members of a group cannot communicate, identify and correct the ne
twork problems. This restores the group
to normal full operation, including network communication.
spare Disk drive is a spare drive. None needed; informational.
unsupported-version Disk drive cannot use the firmware
running on
the member.
See your PS Series support provider.
Table 15-22: Disk Drive Status (Continued)
Status Description Solution