SIP trunking a DID from a PRI to another 7100

[frontiersd]

I have two 7100s in one campus, one with a PRI and one without.  I'm attempting to forward a single DID from one 7100 to another.  I've got the SIP trunk created, and I can dial by extension using that trunk.  I have a single DID specified in the allow rule from the 7100 with the PRI to the one without, and an auto attendant with an alias of that DID, but calling the DID number in question is only netting a busy signal.

I'm going to take a look fresh today to troubleshoot, but if anyone has any suggestions on the best practices for sending a single DID from a PRI from one 7100 to another, please let me know, or make suggestions on what I may have missed.

[Anonymous]

You need to create a trunk group that contains the SIP trunk on the 7100 with the PRI in it.  Then you will then add the DNIS you are receiving from the carrier for that DID as an accept template in that group.  This will get the first 7100 to send the inbound call from the PRI to the SIP trunk hitting the second 7100.  Make sure that the digits sent are understood by the second 7100 for routing.

[dmac · Accepted solution]

On both SIP Trunk Accounts, be sure to uncheck the "Reject External" option to allow trunk to trunk transfer/routing other wise the call will be rejected giving a busy signal.

[frontiersd]

All of the various methods of forwarding the DID work provided the trunks aren't set to reject trunk to trunk calling (Reject External).  I caught it this morning via debug voice verbose.  The cleanest way I found to forward a single DID was under Voice/System Setup/System Parameters, where you can add a system DID entry to remap a of DID X to identity Y, and keep your permission call templates clean.