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New Member

SRST question

I am setting up phones at a customer?s DR location. They would like for the phones at this location (DR) and their other branches to be able to dial extension-to-extension over the WAN still after they go into SRST mode. So, it is assumed the CM servers are down but the WAN is up. What is the best way to do this?

Also, what happens when the WAN goes down?




Re: SRST question

I think we need just a bit more information, i.e. is it a central CallManager deployment with all subscribers centrally located? Or does each site have it's own subscriber? Or does each site have it's own cluster. These will all affect the SRST behaviour.

Assuming a centralized approach with all subs in the HQ, in order for phones to talk to each other while CallManager servers are down, they all need to be registered to an SRST gateway. If the gateway is the same, then there is no special work needed, phones can communicate to each other.

If the SRST routers are all different, then all you would need is the appropriate voip dial-peers to send the calls to the SRST routers over the WAN connection (as you said, this would still be available).

Once the WAN goes down, inter-SRST-router communications would not be available.

Let us know if there are other pieces that need answering.


New Member

Re: SRST question

Yes all of the CM server are at the central location. There are now subs at any remote location.

So what happens when the WAN goes down?