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ISDN debug messages

Can anybody please told me what is the meaning of this message

Nov 21 21:27:11.419: ISDN Se1/0/0:15 SERROR: nfas_T3OOS_timeout()

i configured an isdn pri line and the line is up and down and affter i enable debugs i find the following output:

Nov 21 21:35:53.246: %CONTROLLER-5-UPDOWN: Controller E1 1/0/0, changed state to up

Nov 21 21:35:53.246: ISDN Se1/0/0:15 SERROR: service_queue_from_physical_layer: got ISDN_PH_ACT_IND on an active interface?

Nov 21 21:35:53.730: %CONTROLLER-5-UPDOWN: Controller E1 1/0/0, changed state to down

Nov 21 21:35:54.730: %DIAL0-2-MSG:

*Nov 21 19:35:53.731: %CONTROLLER-2-FIRMWARE: Controller Received remote alarm on, line 0 slot 0

Nov 21 21:35:55.526: ISDN Se1/0/0:15 SERROR: nfas_T3OOS_timeout()

and can anybody told me what is t300s timer ?

thanxs a lot,


Re: ISDN debug messages

T3OOS (not zero) is a timer which controls an Out Of Service condition. It was hard for me to find any info on it as well, but in looking through the code it appears to be used for re-establishing layer 2, in the event of any failure. By default it is set to 5 seconds (that may depend on the HW and SW rev).

You might review the controller stats to see if there are any errors, and have the carrier test the line to confirm its integrity.

Re: ISDN debug messages

Could this be an incorrectly defined isdn switch type?

Either that, or a line sync problem.

What do you see when you do a sh contr E1?

Cisco Employee

Re: ISDN debug messages

Looks to me that the E1 controller is flapping...Is NFAS configured for E1/PRI lines?? Here is i think the bug CSCdz28416 which is reflecting the same issue for the error message

ISDN Se1/0/0:15 SERROR: nfas_T3OOS_timeout()

Try to get the resolved images..

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