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New Member

ISDN Problem with Cisco 2610 Router

I have 2 sites connected to my site. Each of them is connected to me through ISDN link to a separate 2500 series Cisco router in my site and all work fine.

I wanted to gather the two connection in one Cisco 2610 router which equipped with a 8-port ISDN module. I have copied the configuration for each connection's dialer, which is working fine, to the new router.

The problem is when I use the old separate conf. the connections work fine BUT when I use the single 2610 router conf. the two lines work fine for a while ,maybe 5-10 minutes, then one line drops then comes up and the other may drops and so on.

What is wrong?

Is there a special requirements for the ISDN lines to work with the 2610 router's ISDN module?

NB.: I've tested the conf. with two different Cisco 2610 routers.

The IOS ver. is 12.0


Re: ISDN Problem with Cisco 2610 Router

Hard to say what is wrong without seeing the config. First of all, I would suggest you at least ensure you have the latest 12.0 code (if not something newer like 12.1) to to make sure the IOS will cause you problems.

Next, if you never need to dial the remotes, they will only be dialing you, then you should not need any dialer interfaces or dialer configs; you would simply have the PPP commands.

If you do need to dial the remotes, then the simplist would be a rotary-group config:

If you need to have different configuration parameters for each site, then you would need to use dialer profiles:

After reviewing the config, if you still have problems you can have a look at "debug dialer", "debug ppp neg", and "debug isdn q931" to see who and why the connections are being torn down.

New Member

Re: ISDN Problem with Cisco 2610 Router

Dear Sir,

I do appreciate your reply.

If you want me to post you the config. of the first routers(2500 to 3640(remote) and 2500 to 2610(remote)) and the new ones (2610 to both remote (3640 and 2610)) I can do that.

Best regards,

Osama AlEmam


Re: ISDN Problem with Cisco 2610 Router

If after looking at the documentation and debug, you are still having problems, then go ahead and post the 2600 info and we can help out.