Acer Altos EasyStore - Removing Hard Disks or Responding to Disk Failure

Altos eas
y
Store Manua
l
Appendix
B Disk Configurations
151
Removing hard disks or responding to disk failure
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, t he
da
t a associated with that disk is no longer available, bu t the da t a on all the other
disks
remains available.
In a RAID configuration, the ef f ect o f 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,
bu t 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 t he disks are YELLOW . Removing any
one
of them will cause the RAID to be degraded, bu t all the da t a will still be available .
However , af t er you remove one disk, all the other disks become RED , since removing
any one of them at this point will cause the entire RAID t o fail.
Note: I n a linear configuration, the Hotplug I ndicator is RED for all the disks
because
removing any one of them will remove data from the storage system .
However , this will no t adversely affect any of the other disks.
In addition, while a disk is being rebuilt, all the o t her disks are RED, since
removing
any one of them at this point will cause t he 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 abou t 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 f rom slo t 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 dif f eren t slots, but they must be re-ins t alled in t he
opposite
order from which they were removed.