SIP trunk redundancy

Unanswered Question
Oct 1st, 2009
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I have CUCM cluster (1 publisher and 1 subscriber) and I have to configure SIP trunk to telephone provider.

They need my IP address for SIP trunk. Subscriber is the one that is doing call processing (CUCM 6.1.2).

Do I give them IP address of Subscriber or Publisher and Subscriber?

What happenes if my Subscriber stops working and I give them only IP address of Subscriber, will my SIP trunk work?

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Overall Rating: 4 (1 ratings)
KonradStepniewski Thu, 10/01/2009 - 23:32
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If you give them just one IP (Sub) and your Sub will be down then SIP trunk wont work.

Why don't you give them Sub and Pub IPs? Sub IP will be main one and Pub will do backup job. I assume that your Pub will do call processing in case of Sub failure.

Jonathan Schulenberg Sat, 10/03/2009 - 17:14
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CUCM is not intended to perform offnet SIP trunking directly for this and a long list of other reasons. You should be using a CUBE at the edge to interface with your ITSP. This has been addressed at length in several other threads; please run a search.


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