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New Member

ISDN Backup question

We are planning an infratucture with point to point links from all offices to our main location as the primary link. We will be using ISDN DDR as backup if the T1 links fail. Can we configure the DDR to dial a secondary number in case of failure on the first number? Any help is greatly appreciated.

Thank you,

Bryan Mann

New Member

Re: ISDN Backup question

Yes, use the DIALER-MAP IP construction. DDR will grab whatever b-channel is available (not necessarily, but usually the first one) and try to dial the number in the first dialer-map it finds. If it cannot complete the call on that number, it will automatically look for another dialer-map when dialing the next time through. I've seen as many as 3 different numbers with dialer-mapped to the same IP address, but don't know right off hand what the IOS limit is.

New Member

Re: ISDN Backup question

Thanks. Will try it.