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New Member

ISDN BRI - debug output


I am having follwoingg output of debug ISDN commands. I am same output for many routers. ( unfound b cahnnel).

What could be the reason ? It is unable to bring up the interface. It doesnt seem to be IOS problem as same IOS is working at other places. Can it be a problem with Service provider some settings in ISDN switch ?

Debug output is

ISDN BR0 EVENT: process_rxstate: ces/callid 1/0x8008 calltype 1 HOST_DISCONNECT_ACK Nov 19 09:07:14 CET: ISDN BR0 **ERROR**: host_disconnect_ack: Unfound B-channel on Disconnect_Ack call id 0x8008.

Thanks in advance


Re: ISDN BRI - debug output

please provide output of 'show isdn status' as well as the 'show config' output.

(this will help us greatly in helping you)

also output from the 'debug isdn q921' at any time and 'debug isdn q931' while attempting a call will be helpful.

New Member

Re: ISDN BRI - debug output

Hey ,

Here are the codes for disconnect . Becoz i dont see ur complete output after ping + debug q931 -- kindly check the code in the following link.

if more help needed ..paste the above mentioned + sh isdn status.

Suspect a Telco issue. <<

rate the post if helps ....

New Member

Re: ISDN BRI - debug output

Hi, MR. Pushkar,

Ya , I will definitely post the debug output of isdn q931. but it flashes the same error as mentioned in my first earlier post.

And unfortunately there is no dicumentation of that error.

If you have any idea where i will get documentation , pl. let me know. I would appreciate.

Thanks and advance


Hall of Fame Super Silver

Re: ISDN BRI - debug output


I believe that Greg has asked a very good question when he asked you to post the output of show isdn status. I believe that I have seen the error message about unfound channel when there was a problem with the ISDN connection. I suspect that the output of debug isdn q921 would show that there is no communication to the ISDN switch. But show isdn status would be a good first step.