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New Member

IP ospf demand Circuit over ISDN!!!!!!!!!!!!!!


I try to install ip ospf demand circuit over ISDN, but the Hellos are not supressed, as soon the main link goes down , the isdn doesn`t come up. When i do it manualy i dont get any neighbor through this link.

My interface is set to p-to-p, but i also tryed with p-to-mp nothing happen. I also tryed several IOS version, now it runs 12.0.15 , ( should work ).

I no ideas anymore what I can do.

Thanks for any advise.

Regards Philipp

New Member

Re: IP ospf demand Circuit over ISDN!!!!!!!!!!!!!!

Did you configure ISDN as a Backup interface.Also can you post the config.

New Member

Re: IP ospf demand Circuit over ISDN!!!!!!!!!!!!!!


I did not configure the isdn interface as a Backup, because so far as I know, this is not nessecary for on demand Circuit.

Hellos should ba i any case supressed.

Config follows.

Thanks Philipp

New Member

Re: IP ospf demand Circuit over ISDN!!!!!!!!!!!!!!

jusy curious, what triggers ISDN to dial? Normally, you need a floating static route pointing to the isdn interface and appropriate dialer-map and dialer-list to trigger the dial. The ISDN interface wouldn't start dialing on its own. Some "interesting" traffic has to trigger it to dial. Once it is dialed up, all other traffic including OSPF hellos (and all other traffic) can pass through.

The other thing is, if you force it do dial up, can you even ping the other side? Are the OSPF neighboring interfaces in the same area? I know those are silly questions ... but ...

Good luck!