We have a trunk between 2 clusters.
Each cluster has 5 servers spread geographically. 1 is ver 6.1 and the other is ver 7.
In the trunk config we have added sub a b and c for each site.
All works perfectly, except any phones that are subscribed to sub 4 on each site, cannot ring across the trunk.
And if yet If I take out sub 3 and put in sub4 it will work, so in other words All the subs from each cluster need to be defined. yet there is only space for 3.
Is there any way around this?
Do you have a GK Controlled ICT configured?
Usually this happens when the MTP is enabled or disabled, depending on the scenario. Enable the MTP on the sip trunk if it is disabled or disable the MTP if it is enabled.