Sun Microsystems StreamLine SL8500 - Manual (Page 63)

Library Partitioning
96154 • Revision K Chapter 1 Introduction 23
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.