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New Member

Layer 1

Hi,

I am using ISDN(wic-1B-U-V2) and it was working fine but suddenly it stopped to work.And result shows that Layer 1 is deactivated.what does it means?But if I call using NT BOx voice conversation is working fine ..what may be the problem? Please help me.Here is the output of sh isdn sta of Remote and CO.

remote#sh isdn stat

Global ISDN Switchtype = basic-net3

ISDN BRI0/0/0 interface

dsl 0, interface ISDN Switchtype = basic-net3

Layer 1 Status:

DEACTIVATED

Layer 2 Status:

Layer 2 NOT Activated

Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 0 CCBs = 0

The Free Channel Mask: 0x80000003

Total Allocated ISDN CCBs = 0

CO#sh isdn sta

Global ISDN Switchtype = basic-net3

ISDN BRI0/0/0 interface

dsl 0, interface ISDN Switchtype = basic-net3

Layer 1 Status:

ACTIVE

Layer 2 Status:

TEI = 68, Ces = 1, SAPI = 0, State = MULTIPLE_FRAME_ESTABLISHED

Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 0 CCBs = 0

The Free Channel Mask: 0x80000003

Total Allocated ISDN CCBs = 0

4 REPLIES
Silver

Re: Layer 1

Hi

This might be a good starting point for troubleshooting:

http://www.cisco.com/en/US/tech/tk801/tk379/technologies_tech_note09186a0080094b76.shtml#deactivated

Hope this helps

Blue

Re: Layer 1

an ISDN layer 1 not being up is usually due to a misconfiguration, telco problem or physical transmission media problem.

you stated this was working all along, and if no changes to the router have been made, we can probably rule out a 'misconfiguration.

if you've tried replacing the physical media, cat5 cable, NT1 connection, etc. and you're using known good cabling, then we can probably rule out 'physical transmission media problem'.

in most cases, when configuration is correct and cabling proper, the Layer 1 Deactivated is due to a telco problem.

is the telco still provisioning your BRI to you?

has it been disconnected or config changed at the telco switch?

(you should call your telco to confirm the status of their switch as well as perform ISDN testing of the BRI. they usually can determine where the problem is, even if they don't tell the customers, and then get the Layer 1 back to Active)

bottom line, you need Layer 1 activated and Layer 2 TEI assigned & MultipleFrameEstablished before any Layer 3 CCBs can be allocated for calls.

New Member

Re: Layer 1

There is no problem at CO end.

In remote end simply ask your service provider to reset ur connection ...

Did u Check the cable pair with multimeter for dc voltage...compare with standard.

Resently did ur service provider changed the DLC ....if so check for layer 3 hold command.

In this case i have seen voice working but not data....

Change your cable to and from NT Box even ur NT Box incase of having a spare.

Try with this it may solve your problem...

New Member

Re: Layer 1

hey ,

Try replacing the cable b/w your nt1 and router ..if calls are going well it should not be a problem with line ..can be something @ telco end.

just send int debug q931 also once . \

http://www.cisco.com/warp/public/129/isdn_disc_code.html#

see the cause i=" " code in the above link in the output of debug q931 .

Rate if helps

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