CUCME-SRST Cheatsheet

Starting from CUCME 4.0, it provides fallback functionality to IP phones that are registered to CUCM, just like SRST, but provide more robust features like B-ACD during the fallback mode.

Some of the key points for CME-SRST mode:

• First supported with CME 4.0 – IOS 12.4(4)XC
• IP phones re-home to CME in event of CallManager failure & have access to advanced CME telephony features
• Support for up to 240 ephones
• No support for Vg248 registration during fallback
• Lack of support for “alias” command
• Support for Cisco Unity at remote sites (Distributed Exchange/Domino)
• Pickup Groups, Hunt Groups, B-ACD, Call Park,Softkey templates, paging
• Support for CIPC 2.0 with VTA 2.0 on same computer
• No support for secure voice in SRST mode
• Requires more complex configuration

An iPhone app for CME Config Generation:
http://itunes.apple.com/us/app/cme-config-generator/id453025819?ls=1&mt=8

The call-manager-fallback command, which is used to configure Cisco Unified SRST, cannot be used on a router that is configured for Cisco Unified CME

Sample Configuration:
telephony-service
srst mode auto-provision all
srst ephone template 1
srst ephone description CCME-SRST MODE : Oct 31 2006 19:00:20 : Nov 01 2006 00:31:17
srst dn template 1
srst dn line-mode dual
max-ephones 144
max-dn 288
ip source-address 1.4.19.1 port 2000
max-conferences 8 gain -6
transfer-system full-consult
create cnf-files version-stamp Jan 01 2002 00:00:00