Calls dropping at random both inbound and outbound on SIP trunk

I’ve been experiencing dropped calls at random on both incoming and outgoing calls. I’m currently running asterisk and FreePBX

MPLS network and no NAT is being used or required.

I use two boxes that trunk calls between each other with no problems also using a sip trunk. The problem is when a call enters or leaves one of my boxes to our SIP provider it will drop at random and this issue started to surface when I moved to 1.8 from

I have opened a ticket with my provider they aren’t seeing anything but just reporting back that the call has ended. Since, I don’t seem to be having any issues between my PBX’s for internal calls and my SIP trunk provider doesn’t seem to be able to identify the issue. I did run accross an recently opened ticket about incoming call being dropped but not sure if this is the same issue. sendrpid=no and reinvite behavior.

Appreciate any suggestions.


How is your system connected to your SIP provider.

This problem is symptomatic of a firewall issue.

directly via the same MPLS that my PBX’s are on. No firewall between my boxes and SIP provider. Dualed homed boxes with each havinga direct x-connect into their SIP switch. This all seemed to work fine on 1.4 and there has been no physical changes to the setup.


Both boxes reside on the MPLS with no firewalls to our SIP provider (directly connected). Issue started to surface when I went from 1.4 to 1.8