Removing Hard Disks Or Responding To Disk Failure - Acer Altos EasyStore User Manual

Appendix B

Removing hard disks or responding to disk failure

151
The effect of removing hard disks from your storage system or disk failure varies,
depending on the disk configuration you chose when you configured the system and
the current state of the existing disks.
For example, in a linear configuration, when you remove a disk or a disk fails, the
data associated with that disk is no longer available, but the data on all the other
disks remains available.
In a RAID configuration, the effect of disk removal/failure varies, depending on the
RAID level and whether the RAID is in a normal or degraded state. You can
determine the effect of disk removal/failure by looking at the Hotplug Indicator on the
Disks page. If this indicator is GREEN, disk removal/failure will have no effect
on the RAID. If this indicator is YELLOW, disk removal/failure will cause RAID
degradation, but you will still be able to access all the data. If the indicator is RED,
disk removal/failure will cause the entire RAID to fail.
For example, in a RAID 5 configuration, all the disks are YELLOW. Removing any
one of them will cause the RAID to be degraded, but all the data will still be available.
However, after you remove one disk, all the other disks become RED, since removing
any one of them at this point will cause the entire RAID to fail.
Note: In a linear configuration, the Hotplug Indicator is RED for all the disks
because removing any one of them will remove data from the storage system.
However, this will not adversely affect any of the other disks.
In addition, while a disk is being rebuilt, all the other disks are RED, since
removing any one of them at this point will cause the RAID to fail.
If you remove a viable disk and cause only RAID degradation, you can re-install the
same disk and resume normal operation. (For information about adding a disk, refer
to "Adding hard disks".)
Note: If you remove two or more disks, you must re-install them in the reverse
order to help maintain data integrity. For example, if you remove disk A from slot 1
and then remove disk B from slot 2, you must re-install disk B first, then disk A.
You can put the disks back into different slots, but they must be re-installed in the
opposite order from which they were removed.
Disk Configurations
Altos easyStore Manual