HP StoreEver MSL6480 Tape Library User and Service Guide Addendum (QU625-96016, October 2013)

Figure 5 Data path port failover example configuration
2. Standby data path1. Primary data path
4. Standby data path3. Primary data path
6. Dual-port FC tape drive5. Dual-port FC tape drive
HP LTO-5 and LTO-6 control path failover overview
Library control path port failover (see “Control path port failover example configuration” (page 14))
may be configured with one drive hosting the path to the library controller and a second drive
configured as an alternate standby path to the library controller. The library connections will share
physical links with the drives but the library will have its own identity on the SAN. If data path port
failover is also configured, the library control path will follow the data path on link failures.
If the drive hosting the library control path fails, the library web interface may be used to take the
control path drive offline and the library control path identity (world wide names) and all settings,
(such as reservations and prevent/allow settings), will be moved over to the alternate master drive
automatically. When properly configured, the change is minimally disruptive to the host and does
not require any configuration changes on the host or in the backup application.
If no library commands are sent while the port is being reconfigured, the port change happens
with virtually no disruption to the SAN. Commands sent while the port is being reconfigured cannot
be processed and will fail. Applications that retry commands are able to use the library following
reconfiguration of the port. Applications that do not retry can be restarted remotely without making
any hardware configuration changes.
HP LTO-5 and LTO-6 control path failover overview 13