Some storage devices have controllers configured as PRIMARY and SECONDARY as part of the array configuration. The secondary paths may operate at a lower performance level than the primary paths. The multipathing software uses the primary path to talk to the storage device and to keep the secondary path on standby.
In the event of a primary path failure, the multipathing software automatically directs all I/O traffic over the secondary path, with the primary path taken offline. This process is called a “failover” operation. When the failure associated with the primary path has been repaired, the multipathing software automatically directs all I/O traffic over the primary path and keeps the secondary path standby as before. This process is called a failback operation.
You can disable the automatic failback operation so the multipathing software does not automatically failback to the primary path. Later, after the failure associated with the primary path has been repaired, you can do a manual failback operation using the luxadm command. For more information, see luxadm(1M).