For anybody that comes across this post and is looking for a solution, here is what we found.
- This issue was only related to TLS outbound trunk connections for CHAN_SIP.
- The issue didn’t always occur on Vanilla installs… but did sometimes
- The issue definitely occurred after upgrading the core of FreePBX (distro upgrade)
It turns out this was actually related to the Phone Servers being virtualized. We are running them on VM Ware eSXi 6.0u3 on Dell PowerEdge R710 servers. It has something to do with the network card and how it is passing data. We are currently using the VMXNET3 Virutal Cards. It’s possible that switching to the tried and true E100 would have also fixed this issue or even doing direct SRV-IOV Pass through… however we do not think we will need to.
The VM Ware tools needed installed/reinstalled after upgrading the Phone Server to the newest stable distro version. Once we did this, we have had rock solid connections. We were tipped off by a comment in this article from Renrick McDonald (http://www.asteriskguru.com/tutorials/peer_is_now_unreachable.html) that indicated similar issues when using VirtualBox but not when using Hardware install.
We followed this post to install the VM Ware tools on FreePBX
We followed this article for distro upgrades to upgrade the phone servers that we don’t pay for System Admin on:
https://wiki.freepbx.org/display/PPS/FreePBX-Distro-10.13.66
Also we found that after making all of the updates, the system received a new MAC Address. We followed this article to change the Eth1 back to Eth0 which had all of our static info on it. Alternatively we could have just change the VM to static the old MAC Address and this would have also fixed the issue.