In NIC switching mode, "automatically perform fail-back immediately after recovering the faulted transfer path" or "perform fail-back when the transfer path currently used encounters a failure" can be defined by using a standby patrol function.
For information on the setup, Figure 2.41 Automatic fail-back function shows the outline of the automatic fail-back function.
Figure 2.41 Automatic fail-back function
When a device other than HUB is specified as a monitoring target device, the automatic fail-back may not be immediately executed after the primary interface is recovered, depending on where an error occurred in a transfer route. Therefore, make sure to specify HUB as a monitoring target device to execute the immediate automatic fail-back.
Note
After the failed interface is recovered, if a running interface fails before the Standby patrol detects the No.885 message indicating interface recovery, NIC switchback will not be executed. If this occurs, the Standby patrol will consider that both of the NICs are disabled until it detects the failed interface recovery. Recover the interface referring to "4.5.2 Recovery procedure from line failure in NIC switching mode".
