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New Member

SDH Switching causes router interface flapping

I have a problem with customer. They have 4 DS3 links with us. And their DS3 links fluctuate continuously whenever there is a switching on my SDH backbone. Ideally the router should never see the SDH switching because the switching time would be very small, less than 50ms. And this does not happen on their direct connectivity with us, but some other part of my backbone network which is on the path to their destination. But the router DS3 interface goes down for every switching on the backbone, and takes a few seconds to come up again. This is affecting them because they run voice on these DS3 links.

This is 7200 router. Any idea why this might be happening, and how it can be resolved? Any command that can be configured to work around this problem?


Re: SDH Switching causes router interface flapping

Configure serial interface command "carrier-delay" can improve the stability of pe-ce link in the case of e1 error burst.

New Member

Re: SDH Switching causes router interface flapping

hi aghaz..thanks for your response. I tried this command but still hasnt helped. i set a delay of 100 msecs and my DS3 interfaces are still flapping. should i set a higher value or is there something else that could be the problem? Would the interface be bad ?

Re: SDH Switching causes router interface flapping

Hi, I've the same problem. Do you found a solution?