Diamond Storage Array Installation, Operations, Maintenance Manual

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ATTO Technology Inc. Diamond Storage Array Installation and Operation Manual
6.2 RAID Level 0
The Diamond Storage Array can be set up into RAID Level 0 (striping) groups to allow it to read and
store data at a higher transfer rate. QuickRAID0, a CLI command, allows you to set up the system as if
it were a single drive instead of separate drives.
CAUTIONCAUTION
Setting RAID configuration causes all
previous drive data on the Diamond
Storage Array to be erased. Make sure all
information is backed up before setting up
RAID groups.
RAID Level 0 groups provide data that is striped
across several drives. The
QuickRAID0
command, accessed through the CLI or the
ExpressNAV interface, sets up the Diamond
Storage Array into evenly-sized RAID Level 0
stripe groups. Each stripe group is a virtual drive
named with its own LUN (logical unit number).
With a fully populated array, RAID 0 may be
configured as 1, 2, 3, 4, 6, or 12 LUNs. If you set
up RAID0 1, all 24 drives are configured as a
single stripe group. You may also configure two
LUNs of 12 drives each, three LUNs of eight
drives each, four LUNs of six drives each, six
LUNs of four drives each and 12 LUNS of two
drives each. (See Exhibit 6.2-1). The
QuickRAID0 command assumes there are 24
drives available.
Sled-based versus disk-based
RAID Level 0 can be configured one of two ways,
sled-based or disk-based. The default is sled-
based.
Sled-based Use sled-based if an external RAID
controller controls the Diamond Storage Array to
ensure that both drives on a sled will be members
of the same RAID group (LUN). Removing one
sled will not affect other LUNs.
Drive-based QuickRAID0 designates each
drive on a sled as a either partner 1 or partner 2.
Stripe groups are made by combining all partners
designated as 1 together, and all partners
designated as 2 together. Removing one sled will
affect more than one LUN because each partner
will belong to a different LUN.
To set up RAID Level 0 groups
1 Connect to the array via the RS-232 port or the
optional Ethernet management services card
(refer to
Accessing the Array on page 17). You
should now be in CLI.
2 Continue with the CLI or access the RAID page
of the ExpressNAV interface (refer to
ATTO
ExpressNAV: Browser-based Interface
on page 25).
Note
Because ExpressNAV pages take you through
this process easily, the following instructions
are based on the CLI commands. Use these
instructions as a guide in ExpressNAV.
3 QuickRAID0 options are 0, 1, 2, 3, 4, 6 and 12
RAID groups, sled-based or drive-based. The
number indicates the number of RAID groups.
Sled or drive indicates the way you want the
array striped. The QuickRAID0 command will
divide the total number of drives in the same
array equally by the number called out in the
command. Type
set QuickRAID0 [0|1|2|3|4|6|12]
[DRIVE|SLED]
4 The array will update
NVRAM. The Ready
*
displays.
5 Type
SaveConfiguration.
6 Type
FirmwareRestart to
reboot the array.
24 physical drives
An example of RAID 0 configuration (QuickRAID0 4): 2 or more physical drives
into 1 or more virtual drives
RAID 0 subsystem example:
4 virtual devices