Command Reference Guide

188 ● ip address unnumbered 3Com Router 5000 Family and Router 6000 Family
Command Reference
ip address unnumbered
Purpose Use the ip address unnumbered command to enable an interface to borrow the
IP address of another interface.
Use the undo ip address unnumbered command to disable this function on the
interface.
Syntax ip address unnumbered interface interface-type interface-number
undo ip address unnumbered
Parameters interface-type
Name of the unnumbered interface.
interface-number
Serial number of the unnumbered interface.
Default By default, the interface does not borrow IP addresses from other interfaces.
Example Display how to make the serial interface 0/0/0 encapsulated with PPP borrow the
unnumbered IP address from Ethernet interface 0/0/0.
[3Com-Serial0/0/0] ip address unnumbered Ethernet 0/0/0
View This command can be used in the following views:
■ Interface view
Description This command is used to enable serial interfaces encapsulated with PPP, HDLC, Frame
Relay, SLIP or Tunnel to borrow IP addresses from Ethernet interface or other
interfaces. Ethernet interfaces however cannot use unnumbered IP addresses.
The interface that uses an unnumbered address has no IP address itself. Its route
cannot be added into the routing table as a result. For connectivity purpose, you must
configure two static routes for it. For more information, refer to the “Routing
Protocol” part of this manual.