Restrictions for Configuring Unnumbered Ethernet Interfaces

The following restrictions apply when you configure unnumbered Ethernet interfaces:

The unnumbered-address statement currently supports the configuration of unnumbered Ethernet interfaces only for the IPv4 address family. Unnumbered Ethernet configuration for families other than IPv4 is not supported.
You cannot assign an IP address to an Ethernet interface that is already configured as an unnumbered interface.
The donor interface for an unnumbered Ethernet interface must have one or more configured IP addresses.
The donor interface for an unnumbered Ethernet interfaced cannot be configured as unnumbered.
An unnumbered Ethernet interface does not support configuration of the following address statement options: arp, broadcast, primary, preferred, and vrrp-group. For information about these options, see Configuring the Interface Address.
Running IGMP and PIM are supported only on unnumbered Ethernet interfaces that directly face the host and have no downstream PIM neighbors. IGMP and PIM are not supported on unnumbered Ethernet interfaces that act as upstream interfaces in a PIM topology.
Running OSPF and IS-IS on unnumbered Ethernet interfaces is not supported.
You cannot configure this feature on the TX Matrix platform.
The configuration of unnumbered Ethernet interfaces is not supported when graceful Routing Engine switchover (GRES) is enabled on the router.