PSTN Call in SRST Mode

[linlinoo]

Hi, 

I have CUCM 10.5 on HQ and SRST mode router in branch. For all branch PSTN call, I would like to pass PSTN call via SRST router (Not passing HQ). How to deploy on SRST router ? 

[bichacko]

Hi,

You can use what's called Standard Local Route Group concept on CUCM.

Create separate device pools and assign them as per site requirement.

Here's a forum that would help you:

https://community.cisco.com/t5/ip-telephony-and-phones/why-do-we-use-the-quot-standard-local-route-group-quot-in-cucm/td-p/2794912

A PDF:

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/8_5_1/ccmfeat/fsgd-851-cm/fslrg.pdf

[linlinoo]

Thanks,

BTW, If we use router as CME SRST on branch, Do we need to configure ephone dn, ephone, etc.. on Branch SRST router ? or If we done call-manager fallback command, every ephone dn is automatically sync from HQ CUCM to SRST router ? Let's say, firstly, phone 1 is registered to CUCM with 1001 extension. After WAN link is failed, that phone can get 1001 extension from SRST router ?

[bichacko]

Hi,

So when you configure a router for SRST (CUCME or call manager fallback), it retains the configuration that it had (as far as DN etc goes) while it was registered to CUCM.
There possibly might be a few limitations to it, however, not that major.

Here a document that explains the SRST functionality:

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucme/admin/configuration/manual/cmeadm/cmesrst.html

Goto sections: SRST Fallback Mode Using Cisco Unified CME


Please do rate if helpful.
Thanks,
Bijo