Cisco CUCM as primary and Avaya Call manager as Secondary

[inhamit]

Hi, We have requirement to use Cisco CUCM as primary call manager at one of the location via WAN. When there is WAN outage, all phones in that location should work via local Avaya call manager. Could you please suggest what kind of configuration I should apply. We have few IP phones from avaya and few from Cisco.

[Roger Kallberg]

I can’t see how this would work. AFAIK the phones cannot be managed by two different calling systems at the same time.

[Nithin Eluvathingal]

Your proposed solution is not viable; the phones cannot failover from CUCM to Avaya. In your case, you need to utilize a Cisco Router that supports the SRST feature and position it at the location connected via the WAN. In this setup, during a WAN outage, phones registered with the CUCM from this location can register to the Router.

This is the sole feasible solution.

[inhamit]

Thanks. Quick question, with Avaya phones works on Cisco SRST mode?

[Nithin Eluvathingal]

To the best of my knowledge, the answer is no.

Avaya phones are third-party devices, and for these phones, you need to manually define the SIP server if im not wrong to register with the call manager.

[Roger Kallberg]

Definitely a no on that as @Nithin Eluvathingal wrote.

[inhamit]

I can see there are multiple sip proxy server configurations are available in ip phone. Cant we use proxy server 1 to cucm and proxy server 2 to Avaya call manager? What will be the drowback here?

[Roger Kallberg]

That won’t work.

[inhamit]

Thanks. I wonder, what is benefit of having fields for multiple sip proxy server in ip phones?

[Roger Kallberg]

To have multiple servers to connect to in the same phone service platform.

[inhamit]

Thanks for the help. We are planning to have a link between Avaya and Cisco CUCM to make calls between facilities. in this case, can we access the call directory of both servers on IP phone's? LIke Phones connected to Cisco CUCM, will able to search the directory numbers which are configured on Avaya server and vice versa?

[Roger Kallberg · Accepted solution]

You can have a link between the two call services, but the phone is going to be having a connection with one type of service, not both. So no that’s not going to work