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 2.39 Automatic fail-back function shows the outline of the automatic fail-back function.
Figure 2.39 Automatic fail-back function
When specified other than HUB as a monitoring target device, occasionally automatic failback is not promptly executed after recovered the primary interface, depending on where an error occurred in a transfer route. Therefore, specify HUB as a monitoring target device to execute prompt failback.
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".
