CLI Guide
ipv6 unnumbered
Congure a tunnel interface to operate without a unique explicit IPv6 address and select the interface from which the tunnel will borrow its
address.
Syntax ipv6 unnumbered {interface-type interface-number}
Use the no ipv6 unnumbered command to set the tunnel back to default logical address. If the tunnel was
previously operational, this will make the tunnel interface operationally down, unless the tunnel also has an IPv4
address congured.
Parameters
interface-type
interface-number
Enter the interface type, followed by the type, slot and port information.
Defaults None.
Command Modes INTERFACE TUNNEL
Supported Modes Full–Switch
Command History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.4(0.0) Introduced on the MXL.
Usage Information
The ip unnumbered command will fail in two condition:
• If the logical ip address is congured.
• If the tunnel mode is ipv6ip (where ip address over tunnel interface is not possible).
To ping the unnumbered tunnels the logical address route information should be present in both the ends.
NOTE: The ipv6 unnumbered command can specify an interface name that does not yet exist, or does
not yet have a congured IPv6 address. But the tunnel interface will not go operationally up until it has
determined a logical address to use of at least one address family.
Tunneling 1299