AMCC 9500S Computer Accessories User Manual


 
Controller Object Commands
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stripe=Stripe consists of the stripe size to be used. The following table
illustrates the supported and applicable stripes on unit types and controller
models. Stripe size units are in K (kilobytes). If no stripe size is specified,
64K is used by default, if applicable. If you need to change the stripe size after
the unit is created, you can do so my migrating the unit.
group=3|4|5|6|7|8 indicates the number of disks per group for a RAID 50
type. (This attribute can only be used when type=raid50.) Recall that a RAID
50 is a multi-tier array. At the bottom-most layer, N number of disks per group
are used to form the RAID 5 layer. These RAID 5 arrays are then integrated
into a RAID 0. This attribute allows you to specify the number of disks in the
RAID 5 level. Valid values are 3, 4, 5, 6, 7, and 8.
Note that a sufficient number of disks are required for a given pattern or disk
group. For example, given 6 disks, specifying 3 will create two RAID 5
arrays. With 12 disks, specifying 3 will create four RAID 5 arrays under the
RAID 0 level. With only 6 disks a grouping of 6 is not allowed, as you would
basically be creating a RAID 5.
The default RAID 50 grouping varies, based on number of disks. For 6 and 9
disks, default grouping is 3. For 8 disks, the default grouping is 4. For 10
disks, the default grouping is 5, and for 12 disks, the disks can be grouped into
groups of 3, 4, or 6 drives (the group of 4 drives is set by default as it provides
the best of net capacity and performance). For 15 disks, the disks can be
Table 7: Supported Stripe Sizes (KB)
Model R0 R1 R5 R6 R10 JBOD Spare R50 Single
7K/8K 64 N/A 64 N/S 64 N/A N/A N/S N/S
128 128
256 256
512 512
1024
1024
9000
a
a. Models 9500S, 9550SX, and 9590SE
16 N/A 16 N/S 16 N/A N/A 16 N/A
64 64 64 64
256 256 256 256
9650SE 16 N/A 16 16 N/A N/A 16 N/A
64 64 64 64 64
256 256 256 256