Administering Multipathing Groups With a Single Physical Interface

When you have only one network adapter in the multipathing group, failover is not possible. However, you can sill use a multipathing group for failure detection on that NIC.

In the case of a single adapter in a multipathing group, you do not have to configure a dedicated test IP address for failure detections. You can use a single IP address for sending data and detecting failure. If you choose to configure an IFF_NOFAILOVER address for a single adapter in a multipathing group, in.mpathd sends probe packets by using that address. Otherwise, in.mpathd picks a data address to send probe packets. Unlike the multiple physical interface instance, you should not mark a single physical interface as deprecated.

For single adapter groups, use the following syntax to configure an IPv4 address:

# ifconfig interface-name -failover group group-name

You can also use the following syntax:

# ifconfig interface-name group group-name

For IPv6, use the following syntax:

# ifconfig interface-name inet6 -failover group group-name

You can also use the following syntax:

# ifconfig interface-name inet6 group group-name

When the daemon detects failures, the interface is marked and logged appropriately on the console.

You cannot verify whether the target that is being probed has failed or the NIC has failed. The target can be probed through only one physical interface. If only one default router is on the subnet, turn off multipathing if a single physical interface is in the group. If a separate IPv4 and IPv6 default router exists, or multiple default routers exist, more than one target needs to be probed. Hence, you can safely turn on multipathing.