Proware EP-2243D-F4S3, User Manual

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Fibre to SAS/SATA II RAID Subsystem
66 User Manual
takes longer. No Init (To Rescue Volume) is used to create a Volume Set without
initialization; normally used to recreate Volume Set configuration to recover data.
Stripe Size:
This parameter sets the size of the stripe written to each disk in a RAID 0, 1, 0+1, 5
or 6 Volume Set. You can set the stripe size to 4 KB, 8 KB, 16 KB, 32 KB, 64 KB, or
128 KB.
A larger stripe size produces better-read performance, especially if your computer does
mostly sequential reads. However, if you are sure that your computer does random
reads more often, select a small stripe size.
NOTE: Stripe Size in RAID level 3 can’t be modified.
Cache Mode:
The RAID subsystem supports two types of write caching: Write-Through and Write-Back.
Write-Through: data are both written to the cache and the disk(s) before the write
I/O is acknowledged as complete.
Write-Back: when data is written to cache, the I/O is acknowledged as complete,
and some time later, the cached data is written or flushed to the disk(s). This
provides better performance but requires a battery module support for the cache
memory, or a UPS for the subsystem.
Tagged Command Queuing:
When this option is enabled, it enhances the overall system performance under multi-
tasking operating systems by reordering tasks or requests in the command queue of
the RAID system. This function should normally remain enabled.
Fibre Channel/LUN Base/LUN:
Fibre Channel : Each RAID controller has two 4Gbps Fibre Host Channels (ports).
Select the Fibre port where to map the LUN (Volume Set). Options are:
0 , 1 and
0&1 Cluster . “0&1 Cluster” will make the LUN visible on both Fibre ports.
LUN Base : T h e b ase LUN number. Each LUN Base supports 8 LUNs.
LUN: Each Volume Set must be assigned a unique LUN ID number. A Fibre Port can
connect up to 128 devices (LUN ID: 0 to 127). Select the LUN ID for the
Volume Set.
NOTE: Refer to Appendix 1 for more information about mapping
LUNs/Volumes to Host Channel/Port in Dual Controller Mode.
Volumes To Be Created:
Use this option to create several Volume Sets with the same Volume Set attributes. Up
to 128 Volume Sets can be created.