User manual

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to implement RAID 5 data disks and the fourth drive can be used as a spare
disk. When a physical disk failure occurs, the system will automatically
rebuild the data with the spare disk.
RAID 5 can survive 1 disk failure and system can still operate properly. When
a disk fails in RAID 5, the disk volume will be in “degraded mode”. There is no
more data protection at this stage. If one more disk fails, all the data will be
crashed. Therefore, you must replace a new disk immediately. You can
install a new disk after turning off the server or hot swap the new disk when the
server is on. The status of the disk volume will become “rebuilding” after
installing a new disk. When rebuilding completes, your disk volume resumes
to normal status.
Note: To install a disk when the server is on, make sure the disk volume is in
“degraded” mode. Or wait for two long beeps after the disk crash, then insert
the new disk.
z RAID 6 Disk Volume
RAID 6 disk volume is ideal for important data protection.
To create a RAID 6 disk volume, a minimum of 4 hard disks are required. The
total capacity of RAID 6 disk volume = the size of the smallest capacity disk in
the array x (no. of hard disk–2). It's recommended that you use same brand
and same capacity hard drive to establish the most efficient hard drive capacity.
RAID 6 can survive 2 drives failure and system can still operate properly.
Note: To install a disk when the server is on, make sure the disk volume is in
“degraded” mode. Or wait for two long beeps after the disk crash, and then
insert the new disk.
z RAID 5, RAID 6 Read-only Mode
The drive configuration enters read-only mode in the following occasions:
- 2 drives are damaged in RAID 5
- 3 drives are damaged in RAID 6
The drives in the above configurations are read-only. It is recommended to
re-create new drive configuration in such case.