Today, out of the blue, all our Digium/Sangoma D60 and P310 phones don’t connect anymore while our many D80 phones happily keep working. All our phones connect over TLS via port 5061.
- fwconsole firewall stop
- disabled DST Root CA X3
- renewed LE-cert (allthough still good)
- tcpdump ether host [phone’s MAC address] (not working with any phone though)
I am utterly out of ideas… How can I narrow down the problem? How can I even make sure any traffic from these phones reaches the server?
As you know I am no pro
The D60 and P310 phones have a web-gui, the D80 doesn’t, right?
Maybe all your phones cannot pull the configs anymore, but the D80 somehow does not care and uses the old config file.
Whereas the D60s and P310s somehow switched to standard settings in the GUI?
I know…not very convincing
Takeaway: When weired things happen in your network, check your name servers!
For some strange reason, ours stopped resolving the address to our sip box. Changing to a public name server in the phone settings (NOT google’s 188.8.131.52 or 184.108.40.206!) solved the issue.