manually making line protocol down....

Unanswered Question
Mar 14th, 2007

Hi ,

Is their any command which makes the line protocol on a serial interface down, without shutting down the serial interface...

am using a cisco 2600 series routers..

thanks in advance....

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (2 ratings)
CSCO10892433 Thu, 03/15/2007 - 00:49

Hi, rajesh_colt

One way to do this is to make the encapsulation on both side of the serial link different. For example, encapsulate frame-relay on one side and encapsulate ppp on the other side and then the line protocol will be down.



rajesh_colt Thu, 03/15/2007 - 02:13


Let me try it is live link i need to check at off peak hours....let me check..then i will revert to you....any way thanks....for the advice....

ahmednaas Thu, 03/15/2007 - 02:19

I am curious. Why would you want to bring down the protocol on a live link?

flashsplash Thu, 03/15/2007 - 02:24

depends on what kind of routing protocul ur using u can changes the parameters also there are enough ways to bring down the line protocol. But just as the former poster ask why would u wanted to do that on a live link...

ciao flash

rajesh_colt Thu, 03/15/2007 - 03:00

I have an ISDN link as backup for one serial need to test the backup link is working or not....if I shut down the serial interface ISDN will not fire....Because I have configured backup interface command under serial interface if i shut down the serial interface...the commands also doesnot work out..i have checked that..only my ISDN fires automatically when my line protocol goes down....that only happens when the primary link goes down ...or unplug the serial in order to check ...i need to physically remove the cables from serial order to avoid that ...i need a solution that I can sit in my pc and wanted to make line protocol down...and check ISDN...thats all....

bradlesliect Thu, 03/15/2007 - 03:53

could you paste a copy of your config as well the model of router and IOS version?

Could be an IOS bug and you may need to upgrade.

rajesh_colt Thu, 03/15/2007 - 04:42



I was just replying to ahmednaas previous question....

bradlesliect Thu, 03/15/2007 - 05:05

I understand why he needs to do this. I had a similar issue, and it was IOS related. upgraded the IOS and it solved the problem.

what would be nice is some debug info when you admin shut the link? :)

debug isdn events

debug isdn errors

debug isdn q931

debug isdn q921

Don't do all at the same time though.


This Discussion