Configuring and unconfiguring path failover support

Path failover support is not enabled automatically when the device driver is installed. It must be configured initially on each logical device after installation. When path failover support is enabled for a logical device, it remains set until the device is deleted or the support is unconfigured. The alternate path failover setting is retained even if the system is rebooted.

To enable or disable the support on a single logical device, use the SMIT menu to Change/Show Characteristics of a Tape Drive, select the logical device to change such as smc0, smc1, then select Yes or No for Enable Path Failover Support. The support can also be enabled or disabled by using the chdev command, for example,
chdev -l smc0 -aalt_pathing=yes
chdev -l smc1 -aalt_pathing=yes
chdev -l smc0 -aalt_pathing=no 
chdev -l smc1 -aalt_pathing=no