Sun Microsystems SL8500 manual Partition Configuration Requirements, Hosts and Partitions

Library Partitioning

Partition Configuration Requirements

Only a single library can be partitioned. All pass-thru ports (PTPs) must be disabled before partitioning can be enabled. A library complex with functional PTPs cannot be partitioned (see “Library Complex” on page 19 for details about library complexes).

The smallest unit of measure for a partition is a rail, and a partition can consist of one to four rails. Rails in the partition must be adjacent—for example, a partition can consist of rails 1, 2, and 3, or rails 2 and 3, but not rails 1 and 3 only.

Each rail can be assigned to only one partition.

Hosts and Partitions

Each partition is assigned exclusively to one of the following:

■A single ACSLS host

■A single HSC host

■A group of up to 16 HSC hosts sharing a common control dataset (CDS)

Each partition appears to the host as a separate ACS. An ACSLS server can control one or more partitions in a library, whereas an HSC system can control only one partition in a library.

Rails assigned to one partition are reported to all other partition owners as “unallocated.” Partition owners cannot access or display information about any of the drives, storage slots, or cartridges within partitions assigned to other hosts.

Library Resources and Partitions

All drives, storage slots, and cartridges within a partition are owned exclusively by the assigned host. For example, if rails 1 and 2 are configured for an HSC host, only HSC- designated drives and cartridges can be installed at those rail positions.

All HandBots and CAPs in the library are shared resources which cannot be assigned exclusively to one partition.

Each host must reserve a CAP to use it, and when done, must release the reservation to make the CAP available to other hosts. No other host can access the CAP until the first host has terminated the operation and released the reservation.

If for some reason a host cannot release its CAP reservation, a library operator can use the SLConsole to override (unreserve) the reservation. You should use caution with this procedure, however. See “Overriding a CAP Reservation” on page 54 for the detailed procedure.

Since CAPs are shared resources, they cannot be set to run in auto mode. The commands to enable CAP auto mode are disabled to ACSLS and HSC for a partitioned library.

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