IBM TS2340 User Guide - Page 102
Primary and Alternate Paths
UPC - 883436006873
View all IBM TS2340 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 102 highlights
HP-UX Device Driver (ATDD) After path failover support is enabled, it remains set until atdd_claim or kctune is run with the alternate_pathing driver parameter set to OFF. The path failover setting is retained even if the system is rebooted. If you want to turn off the data path failover feature in the ATDD driver, perform the following steps: In HP-UX 11.0, 11i v1 and v2: 1. Clear the alternate_pathing parameter. (You can ignore the message about rebooting the system.)# /opt/atdd/bin/atdd_failover -a 0 2. Reconfigure DPF for the devices: # /opt/atdd/bin/atdd_claim In HP-UX 11i v3: Run kctune to disable the kernel tunable of atdd_alternate_pathing. ATDD handles the DPF in the next open. # kctune atdd_alternate_pathing=0 * The automatic 'backup' configuration has been updated. * The requested changes have been applied to the currently running configuration. Tunable Value Expression Changes atdd_alternate_pathing (before) 1 1 Immed (now) 0 0 If you want to turn the data path failover feature back on in the ATDD driver, perform the following steps: In HP-UX 11.0, 11i v1 and v2: 1. Set the alternate_pathing parameter. (You can ignore the message about rebooting the system.) # /opt/atdd/bin/atdd_failover -a 1 2. Reconfigure DPF for the devices: # /opt/atdd/bin/atdd_claim In HP-UX 11i v3: Run kctune to enable the kernel tunable of atdd_alternate_pathing. ATDD handles the DPF in the next open. # kctune atdd_alternate_pathing=1 * The automatic 'backup' configuration has been updated. * The requested changes have been applied to the currently running configuration. Tunable Value Expression Changes atdd_alternate_pathing (before) 0 0 Immed (now) 1 1 Primary and Alternate Paths When ATDD is loaded into the kernel, the first logical device that it sees in the system is the primary path for that medium changer. The other logical paths that ATDD attached for the same tape drive are configured as alternate paths. The device driver supports up to 16 physical paths for a single device. In HP-UX 11i v3, the HP-UX system always pickups a best path for ATDD to open so the primary path is dynamically assigned from the system. ATDD does not provide any .atlpath special file. The primary and alternate path information can be obtained by issuing the following command except in HP-UX 11i v3: 84 IBM Tape Device Drivers Installation and User's Guide