It happens suddenly today.
We have CCM cluster 4.23, all the MGCP PRI located at main site, all the remote site make and receive call through main site.
CCM Region is set up as G729 between offices to save bandwidth.
Today, remote office could not receive and make call.
Phone will ring, but it will go fast busy after pick up.
Then I change all the Region to change G711, then everything is fine.
I mean it has been working for years, and suddenly not working today.
Anyone happen before??
P.S. I only upgrade the the MGCP router (2821) to latest code, the router also configure as SCCP for transcoder and conference, then I reverse back to original IOS, but still doesnt work.
Thanks for help..