Multiple IP Unnumbered Loopback interfaces on Cisco 7206VXR (NPE-G1)

rjsatter · ‎09-10-2003

I currently have two 7206VXR routers serving DHCP addresses to several thousand subs. We are in the process of re-IPing the network and want to minimize impact as much as possible.

Can I have two ip unnumbered loopback interfaces active at the same time on one ATM sub-interface? If so we can keep service up for subscribers on the old scope until their lease expires - then they will renew off of the new scope.

Current config below (with fictional IP's)

rbe nasip Loopback10

interface Loopback10

ip address 1.2.3.4 255.255.248.0

interface ATM1/0.200 point-to-point

description IMAS DHCP

ip unnumbered Loopback10

ip helper-address 5.6.7.8

atm route-bridged ip

range pvc 10/33 10/5000

encapsulation aal5snap

didyap · ‎09-16-2003

I don't think two ip unnumbered statements can be added to the same ATM subinterface. The interface can have secondary IP addresses instead. For details on the ip unnumbered configuration refer

http://www.cisco.com/en/US/tech/tk648/tk362/technologies_tech_note09186a0080094e8d.shtml