SIP Trunk Destination Failover

jameskuder · ‎07-03-2014

We are currently running CUCM 8.62 and have a SIP Trunk setup which is configured with the Destination Address of a third party Prod VRU server.

We are in the process of adding a DR server for the third party VRU. Is there a way to configure that SIP Trunk to automatically failover to the DR box if for some reason the Prod box goes offline?

I noticed in the SIP Trunk configuration screen that you can add additional destination addresses and set priorities on the addresses, but I am unsure if that would accomplish what I am looking for or not.

Suresh Subramanian · ‎07-03-2014

Hi,

you can add the IP addresses of the additional DR server in the SIP Trunk Destination addresses, but you cannot set priorities over one another. When an outbound call gets placed, a destination address gets chosen randomly. No preference is given to one destination address over another when all are reachable.

However you can enable SIP Option Ping feature under SIP Profile associated to that trunk.

This will help to track the status of destination addresses configured in the SIP Trunk.

http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/srnd/collab10/collab10/trunks.html#pgfId-1342234

SIP OPTIONS Ping

The SIP OPTIONS Ping feature can be enabled on the SIP Profile associated with a SIP trunk to dynamically track the state of the trunk's destination(s). When this feature is enabled, each node running the trunk's SIP daemon will periodically send an OPTIONS Request to each of the trunk's destination IP addresses to determine its reachability and will send calls only to reachable nodes. A destination address is considered to be "out of service" if it fails to respond to an OPTIONS Request, if it sends a Service Unavailable (503) response or Request Timeout (408) response, or if a TCP connection cannot be established. The overall trunk state is considered to be "in service" when at least one node receives a response (other than a 408 or 503) from a least one destination address. SIP trunk nodes can send OPTIONS Requests to the trunk's configured destination IP addresses or to the resolved IP addresses of the trunk's DNS SRV entry. Enabling SIP OPTIONS Ping is recommended for all SIP trunks because it allows Unified CM to track trunk state dynamically rather than determining trunk destination state on a per-node, per-call, and time-out basis.

//Suresh

Please rate all the helpful posts

//Suresh Please rate all the useful posts.

Gordon Ross · ‎07-03-2014

Have you investigated using SRV records for the SIP trunk destination?

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Suresh Hudda · ‎07-03-2014

If you have cisco cucm cluster with multiple callmanger nodes in place of Prod VRU server, then I am sure it will work by adding all nodes' ip addresses in SIP trunk's destination addresses. But for third party callmanagers I am not sure that it will work. But you can test the same by adding IP address there during a maintenance window.

Moreover, You can add one more SIP trunk for DR setup and keep this trunk and old trunk in RG (Keep old one on top of new) and then assign this RG to a route list so you can point the route pattern to this route list.

But make sure that "stop routing on user busy flag" (in service parameter) is set to false, this parameter has built into the SIP stack in CUCM to allow for redundancy purposes.

Suresh

Ayodeji Okanlawon · ‎07-03-2014

I agree with Gordon here, what you need is DNS SRV records. That will do the trick for you

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jameskuder · ‎07-07-2014

I guess that I am looking for the simplest resolution to complete as well as effective.

Here is more background. The system that we are interacting with is a VRU for a Telephone Banking Application. Customers calling in are routed to it via a menu in UCCX. They press "1" which will route them to the Production VRU via a SIP Trunk. If for some reason the PROD box goes off line, we need that "1" option to automatically route to the DR VRU via the SIP Trunk