Ganesh Hariharan Mon, 01/25/2010 - 22:21
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Question- list of commands and steps to successfully remove old interfaces from router


What exatcly you mean to remove the old interface from router,Physical interface cannot be removed from configuration if any logical interface are been configured in configuration then issue a command no interface lo 1.

Hope to help


samokonski Tue, 01/26/2010 - 06:04
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I have some sub-interfaces under gi0/1 that need to be removed from the config.

Entered int gi0/1 --> no int gi0/1.1.

The configs for those sub-interfaces have been removed from the config but they still show up in (sh ip int br).

How can those unwanted subinterfaces be removed from display when running command (sh ip int br)?

sachinraja Tue, 01/26/2010 - 11:47
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Hi Sam

When you remove a sub-interface, it can still show on the show ip int brief command, but all the configurations would have disappeared.. try reloading the router to remove it off the "show ip int brief" commands.. try it and let us know..


I know this is an old post but didn't see someone has answered it.  To remove a logical interface, type in "no interface gig0/1.1" as you have noted above.  I think the problem why it may not work for you is because you may have typed that command why you were in the interface of gig0/1.  Go back higher level - type exit - then type that command in.

Richard Burts Tue, 11/29/2016 - 09:54
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Actually the suggestion from Raj is the correct answer. Your suggestion seems intuitive but unfortunately will not work. The issue has to do with the way that running-config works. We tend to think of it like a text file (since that is what it looks like in the output of show running-config). But the running-config is actually a dynamic data structure. When you create a subinterface for an Ethernet interface it creates an entry in the data structure. As you add config parameters for the subinterface they are entered under that element in the data structure. If you delete the subinterface (no interface gig0/1.1 - no difference which config mode you are in) it removes the config parameters from the entry but leaves the subinterface entry in the data structure. The only way to remove the subinterface entry from the data structure is to reload the router.




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