Create A Raidset; Initialize The Raidset; Add The Raidset As A Logical Unit - StorageWorks RAID Array 410 Installation Manual

Getting Started - RAID Array 410 for HP-UX
2.7

Create a RAIDset

If you require RAIDsets to be available to the host as Logical Units, you must now combine
disks into a RAIDset. RAIDsets must have at least three members, and can have as many as
fourteen. This example creates two three member RAIDsets using the ADD RAIDSET
command.
SWXRC> ADD RAIDSET RAID_SET_1 DISK100 DISK200 DISK300
SWXRC> ADD RAIDSET RAID_SET_2 DISK400 DISK500 DISK600
In this example, "RAID_SET_1" and "RAID_SET_2" are the names of the RAIDset, and
they are followed by a list of disks to be included in each RAIDset. The names of the RAID
sets are user selectable. Performance of your RAIDsets will be optimized if each RAIDset
includes disks from different channels as shown in the example.

2.7.1 Initialize the RAIDset

Before you can put the RAIDset(s) into service, they must be initialized.
When you initialize a RAIDset, a chunksize must be specified. A chunksize is the number of
blocks of data that is transferred at one time. By using the default chunksize, the controller
will optimize the chunksize by selecting a number equal to the number of blocks in one track
of disk data. We recommend using the default chunksize.
SWXRC> INITIALIZE RAID_SET_1 CHUNKSIZE=DEFAULT
SWXRC> INITIALIZE RAID_SET_2 CHUNKSIZE=DEFAULT

2.7.2 Add the RAIDset as a Logical Unit

To make a RAIDset available to the host computer, you must identify it as a host logical
unit. The unit number is a one or three digit number preceded by "D". The unit number
identifies the controller's target number and the RAIDset as the Logical Unit (LUN)
connected to the target. Units identified with controller target number 0 have a single digit
number which corresponds to LUN number. For example, D5 would be target 0, LUN 5.
Units identified with controller targets 1, 2 and 3 use a 3 digit number. The first digit
corresponds to the controller target number, the second digit is always 0 and the third digit to
the LUN number. For example, D205 would be target 2, LUN 5. You must now identify the
RAIDsets as Host Logical Units by using the ADD UNIT command.
SWXRC> ADD UNIT D0 RAID_SET_1
SWXRC> ADD UNIT D1 RAID_SET_2
This example uses the controller target of 0 (specified earlier with the
SET_THIS_CONTROLLER command) and LUN 0 and 1 as the digits in D0 and D1, since
the two RAIDsets are the first and second units identified on the controller.
2–6
Valid chunksizes are 16 – 682 blocks. You should use a larger
chunksize for applications that make a lot of I/O requests. Use a
smaller chunksize for applications that make relatively few I/O
requests, but need to move large amounts of data with each
request.
NOTE
EK–SMRA3–IG. C01