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Software RAID 5 is not a good choice for writing a lot of very small files!
RAID6: parity algorithm array (required, minimum 4 units - with the same
capacity). You can choose from the List Boxes: (layout)parity-algorithm [left/right]
[symmetric/asymmetric].
DESTINATION
SIZE:
(NR_OF_UNITS-
2)*(SINGLE)UNIT_SIZE, where (SINGLE) UNIT_SIZE is the size of the smallest
unit in array.
The (layout) parity-algorithm in RAID 6 is described below.
RAID 6 (layout) parity-algorithm
It is possible to set one from four algorithms of placement data blocks and parity
blocks in matrix. Our default option is left symmetric which the best is for large reads.
Other recommended value is left asymmetric.
To remove RAID, if previously added to Volume Group please enter console Extended
tools (press F1 on console to find out keyboard shortcuts) and first delete Volume
Group of the RAID (Delete content of units function in Extended tools menu). Then
the Remove button will be enabled. Otherwise simply press Remove button.
You can add spare units to RAID1, RAID5 and RAID6 arrays. Please
remember that after creation of an RAID, in Function: 'Info' will be shown progress of
Synchronization. Until end of this process all actions done on this array will be
performed a bit slower.
If Units are connected through Fiber Channel with only one Storage unit or if
the LUNS(under iSCSI) come from the same target, then its not recommended to
create s/w raids on these Units, because this would slow down the system. If Units
come from two different Storages or LUNS come from two different targets, then you
can create s/w raids with no problem.
Function: S/W RAID e-mail notification
It is possible to send notification by e-mail about events on software RAID arrays (e.g.
rebuild started, rebuild finished, span is active). In order to do so please check Send
array events.
In order to send array events you must enable “E-mail notification” in
“setup”
“administrator”.
Include resyncing/recovering progress
This enables informing about progress of resync/rebuild, if it's currently running. E-
mail will be sent for every 20 % of completed progress.
Include array status
Information about the status of event-related array will be added every event.
Function: Drive identifier
This function helps find disks in the cage of your NAS server. In case of hardware
RAID installed, the whole RAID array is shown as a single drive. In this case you may
not be able to determine which drive unit is which disk when using S.M.A.R.T. tool or
hardware RAID management tool (depends on manufacturer of RAID controller).
