We recently pushed our Asterisk video bridge into a DMZ and since then, local calls have been unreliable to say the least. While offsite calls work nicely, calls on our internal server usually fail to ring the far end. Two test calls that were made 4 minutes apart yielded different results: one rang the far end, the other kept trying to transmit the Invite. The configuration didn’t change at all between the two calls. I’ve been going over the debug logs, but haven’t noticed any possible reasons why one call failed. It’s the same all the way to the part where the far end is called.
The endpoints use different ports for UDP signaling and Asterisk is set to expect UDP packets from those ports. The RTP port range is the same between the ends (at least where it’s configurable), Asterisk and the firewall. All ports that we’re using have been opened in the firewall and incoming UDP traffic is routed to Asterisk. In Asterisk settings, localnet is defined as the LAN that both endpoints are on, externip is the public address of the server. Directrtpsetup and directmedia are both set to “no” and nat is set to “yes”.
So, what could be causing this issue?
Best wishes, Norman