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?
