Repair detection time is twice the failure detection time. The default time for failure detection is 10 seconds. Accordingly, the default time for repair detection is 20 seconds. After a failed interface has been marked with the RUNNING flag again and the failure detection method has detected the interface as repaired, the in.mpathd daemon clears the interface's FAILED flag. The repaired interface is redeployed, depending on the number of active interfaces that the administrator originally set.
When an underlying interface fails and probe-based failure detection is used, the in.mpathd daemon continues probing, either by means of the designated prober when no test addresses are configured or by using the interface's test address.
During an interface repair, how the recovery process proceeds depends on how the failed interface was originally configured, as follows:
If the failed interface was originally an active interface, the repaired interface reverts to its original active status. The standby interface that functioned as a replacement during the failure is switched back to standby status if enough interfaces are active for the IPMP group, as defined by the system administrator.
If the failed interface was originally a standby interface, the repaired interface reverts to its original standby status, provided that the IPMP group reflects the original number of active interfaces. Otherwise, the standby interface becomes an active interface.
For a graphical representation of how IPMP operates during interface failure and repair, see How IPMP Works.