I got a dozen 4331 routers with SRST licenses, but when trying to configure SRST its not functioning. In fallback mode the phones don't get any DNs nor any dial tone. I've got CUCM 10.5 at the central location.
I put both telephony-service and voice register global into esrst mode, since I have SIP and Skinny phones, but I'm not getting it working properly.
I've been doing some research and it seems that there is a product called Unified SRST Manager, a VMware appliance that handles all ESRST.
Am I forced to use that Manager applicance with the latest ISR routers, or can I still do the old way of configuring SRST on the CLI for my SCCP phones?
I did try doing "no mode esrst" on both telephony-service and voice register global. That made telephony-service go back to CME mode, but voice register global now says "mode srst", weird.