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New Member

ISDN-connection to Turkey

Hello all,

I encounter ISDN-errors when i try to connect to a router in Turkey.

Sometimes the ISDN-connection is without any failures and the connection is set up in one time and sometimes is hard set up a ISDN-connection.

Sep 4 11:46:12.056: ISDN BR0 SERROR: L2_Go: at bailout DLCB is NULL

L2: sapi 0 tei 127 ces 0 ev 0x3

Any ideas what may be the problem ??

Kind regards

Edwin van Wijk

New Member

Re: ISDN-connection to Turkey


Turkey is now easy. I know it.....

Is on the remtoside (turkey) the router realy online?

Does the router have a own and fix isdn-number?

Does the company provide a own ISDN S0-Port of the ISDN-Router.

Does the company have enough ISDN-Numbers?

(some companys change isdn-numbers very fast, because they don`t have enougt isdn-numbers)

Good luck.....

Frank (Germany)

New Member

Re: ISDN-connection to Turkey

Hello Frank,

Yes, the remote-router is online.

I managed to configure a connection over the Internet from remote over ISDN.

We need an ISDN-connection as backup in case the connection over the Internet breaks down.

I can see on the remoteside, when i am testing the ISDN-connection, that the router picks up the call, this call last 20 secs and then ends with a 'normal call clearing' but in that moment i can not reach the router by ping or telnet via ISDN.

It seems to be an intermitted problem, sometimes it works and sometimes it does not.


Edwin van Wijk

Re: ISDN-connection to Turkey

van, it might be a problem with either layer 2 or layer 3. Please run a "debug ppp authentication" and "debug ppp negotiation" and see what exactly is the issue.

It might also be a problem with the IOS that you are running. Please post the results of these outputs.

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