4.1.0 HP PolyServe Matrix Server administration guide (T5392-96073, October 2010)

Device identifiers and GPT disks
When the SCL assigns device identifiers to the partitions on GPT disks, it skips the
first partition because that partition cannot be used by Matrix Server. Therefore, the
first identifier, psdXp1, is assigned to partition 2, the second identifier, psdXp2, is
assigned to partition 3, and so on.
Device database and membership partitions
The SCL stores the device identifier and physical UID for each imported disk in a
device database. When you installed Matrix Server, you specified a set of SAN
partitions to be used for the database and for other functions related to SAN control.
These partitions are called membership partitions and are automatically imported
into the matrix. (For more information about these partitions, see “Membership
partitions” on page 242.)
Matrix Server creates the device database on one of the membership partitions and
then replicates it to the other partitions. The database must be present for a matrix
to form. To ensure that the database is always available, the recommended
configuration is a three-way mirror.
You can use the utilities described under “Manage membership partitions” on page
244 to fix any problems with the membership partitions.
Disks containing more than 31 partitions
The maximum number of partitions on a disk or LUN is limited to 31. Disks or LUNs
containing a larger number of partitions cannot be imported into the matrix. If you
upgraded to Matrix Server 4.0 from a release earlier than 3.4, you may currently
have imported disks or LUNs with more than 31 partitions, and may have created
dynamic volumes using those higher-numbered partitions.
The higher-numbered partitions will continue to work correctly; however, you should
be aware of the following:
• A new volume cannot include subdevices having partition numbers above 31.
Existing volumes cannot be extended to include the higher-numbered partitions.
• You will not be able to take a hardware snapshot of partitions with numbers
above 31.
• A single Alert will be issued if any disks or volumes in the matrix contain unsup-
ported partitions. The Alert will remain until the disks with unsupported partitions
are deported.
Configure the SAN72