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Trunk groups and SRST (MGCP -> H323)

I can't seem to get trunk groups working when transitioning to SRST mode. If I reconfigure the trunk groups while in SRST mode, everything works great. But if I reboot the router and then go into SRST the trunk groups fail again. Debugs show that the channel is not available. I've opened a TAC case, and the engineer is suspicious to the fact that trunk groups on the T1 controllers will not work when they are MGCP first, then H323 (SRST trigger).

I've removed the ccm-manager config statement (since that was overwriting the configs on each reboot) so that's not the issue, the config statements are there upon reboot.

So in short, I've got the config working, but only when I enter the config commands while SRST is active.

Can anyone comment on the compatibility of trunk groups and SRST?

Here's a portion of the running config:

controller T1 0/0/0

framing esf

linecode b8zs

pri-group timeslots 1-24 service mgcp

trunk-group uog_pstn_tg timeslots 1-21 preference 2


interface Serial0/0/0:23

no ip address

encapsulation hdlc

isdn switch-type primary-dms100

isdn incoming-voice voice

no cdp enable


voice-port 0/0/0:23


dial-peer voice 929 pots

trunkgroup uog_pstn_tg

destination-pattern 9[2-9].........

forward-digits 10


New Member

Re: Trunk groups and SRST (MGCP -> H323)

I've seen this as well. I haven't found a solution to this yet, have you?