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q921 Debug - Lost communication with remote

Has anyone ever seen a problem with a layer 2 on a PRI interface that displays as "S7_T203_EXPIRY: Lost communication with remote" during a debug of q921? I am unable to find any reference to this on the web or on the Cisco site. This is first time I have seen this. I'm assuming at this point that the D-Channel is not running clean and there is an issue on the provider end.......Anyone have experience with this?


New Member

Re: q921 Debug - Lost communication with remote

This issue is tracked by Cisco bug ID CSCsa73950.

In the vast majority of cases, this message is completely benign and may be seen on a perfectly functioning ISDN link. The wording of the message makes it appear that there is an actual problem. This defect is considered a cosmetic problem and does not interfere with ISDN functions on the Cisco IOS router.

S7_T203_EXPIRY: Lost communication with remote means that while in Q.921 state 7 -- which is MULTIPLE_FRAME_ESTABLISHED state -- the T203 timer has expired. T203 seconds have elapsed without receiving any Q.921 message from the peer ISDN device, which may mean that the remote end has failed. In most cases, the peer device is in full Q.921 communication with the Cisco IOS router, but the T203 timer window is simply short enough that it might expire between regular Q.921 updates from the peer.

You can overcome this problem by upgrading the IOS version to one of these versions: 12.3(14)T4, 12.4(1.8)T, and 12.4(1.8).

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