Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

SIP trunk rollover to PRI

We're using a 3rd party SIP proxy to terminate some 3rd party SIP trunks. We have a SIP trunk between that proxy and CUCM. In addition, we have multiple gateways on our network that terminate PRI's.

I want to use the SIP trunks for outbound LD dialing and roll over to the PRI's when all SIP channels are full or down. For testing, we have 1 SIP channel to a 3rd party provider. If I place a call all works fine through the SIP trunk. When I place a second simultaneous call, I get a busy signal from the SIP proxy. I want CUCM to rollover to a PRI rather than just ring busy.

I have tried adding a PRI in the route list, tried adding a PRI-only route list to the route list group and have also tried adding a second LD (PRI) partition below the SIP partition in the CSS. I have not been able to get CUCM to roll over to our PRI's when the SIP channels are busy/down.

Any thoughts on how to accomplish this? Are we going to have to implement a gatekeeper?


Re: SIP trunk rollover to PRI

Have you tried setting the 'Stop Routing on User Buy Flag' to False?

You can find this option in the Call Manager service parameters page, under Clusterwide Parameters (Route Plan).

This should allow the route list to roll over to the next device in the list.



Please rate if helpful

New Member

Re: SIP trunk rollover to PRI

I think I found the problem. The SIP proxy was returning busy rather than congestion. Once I made that change, CUCM started rolling over correctly. Thanks.

CreatePlease login to create content