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Migrate IP address to other interface

I have a Cisco 2811 with fa 0/0 as my bearer, and a switch module for internal clients.

I have an issue with my fa 0/0 flapping, I want to move that ip configuration to fa 0/1

as this is a branch office I am reliant on the bearer port to give me coms so changing the IP addresses is difficult.

Has any one tried this with a TCL script?

Any other ideas would be appriciated.


Reza Sharifi
Hall of Fame Expert

You should not need TCL script for this.  Have an outage window, copy the commands that are under interface fa0/0 into a notepad. Delete the config on fa0/0 and paste the config from notepad to fa0/1. Test to make sure the connection is up and traffic is passing.


I'm accessing the the router via fa 0/0 as soon as I delete the IP address on the interface, I will lose remote access.

Joseph W. Doherty
Hall of Fame Expert


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Remote access via f0/0 currently?

Haven't tried using a script, but you might update the startup config and schedule a reload.

I'm think about just modifing the start up script but I'm worried I wont have a roll back option.

If I can TCL, then I can schedule a reload change the ip addresses, and if I lose coms to the box it will reload itself and be back to normal.

Sorry for joining the party a bit late.


For future reference, configure replace is your friend: Create a new configuration, and save it on flash:. You probably want to copy over your existing config with TFTP, SCP or similar, make the required changes, and then transfer it back under a different filename (e.g. migration-yyyy-mm-dd.config).


Once the new config file is on the flash drive, schedule a reload, and then use "config replace flash:/migration-yyyy-mm-dd.config" to activate the changes in the new configuration. If you can't contact the router, it should still reload on schedule, with the old configuration in place. If everything goes to plan, simply use "copy run start" to save the new running config.




I think that you use the Event Manager to change, and rollback if necessary.


event manager applet CHANGE-LINK
event timer watchdog time 240
action 0.1 cli command "enable"
action 0.2 cli command "int f0/1"
action 1.0 cli command "" ip address XXX"
action 2.0 syslog priority informational msg "Change link successfully."


My suggestion that you create two schedules at different times, one to change for new interface and other to return. If change is OK, you will remove the scheduled rollback.

The time is to recycle at the period of you determine, caution that this.


Please rate and mark posts accordingly if you have found any of the information provided useful.
It will hopefully assist others with similar issues in the future.

Best regards,
Lucas Freitas