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ISDN BRI module not working in 3640

Dear Experts..

We just purchase 3640 router with 4-port ISDN BRI module, when i PLug in my ISDN line in bri port its layer onee and two not activated and shows me a deactivated status, as follow..

ISDN BRI2/0 interface

dsl 16, interface ISDN Switchtype = basic-net3

Layer 1 Status:


Layer 2 Status:

Layer 2 NOT Activated

Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 16 CCBs = 0

The Free Channel Mask: 0x80000003

Number of L2 Discards = 0, L2 Session ID = 16

We also have a 2522 router with a bri port and the same ISDN line working fine on that router ,,,

when i on my q921 and q931 debug and give this command

isdn call int bri2/0 5436782

it ginves me the messages as follows

*Mar 24 18:07:29.098: ISDN BR2/0: Could not bring up interface

Plzz tell me what i am missing ,,,,, or is there any p[ossibility of IOS bug ( we are using 12.2-7b ) or the faulty BRI module..

Thanks in advance

Muhamed Asif Shaikh

Cisco Employee

Re: ISDN BRI module not working in 3640

try this doc

also try using Cisco Output Interpreter for eg; "show isdn status" command and others, very useful tool;



Cisco Employee

Re: ISDN BRI module not working in 3640

Somehow the Layer 1 on the BRI in 3640 fail to make it to "Active" state...Try to use " shut/no shut under the interface and also "clear interface bri x/x" to see the results..Also try to move the same bri line to other bri port as well..

Here is the place which talks about that too.

And also Layer 2

If its not comaing up at all then may be the card went bad...Tejal

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