3cx Version 11: DNS resolution/Network Failure

[adnanj85]

hi Guys,

I need an urgent help, all of a sudden my sip trunks have started registering it self and then failing it self.
It has started from last month and now keeps on bugging every once a week.
Few days works fine and then again starts giving registration fail DNS/Network Failure issue.
I have reported My ISP: Response no issue
Reported Fonet: Response no issue

Returning Error:
Event source: 3CXPhoneSystem
Registration at 7734 **** has failed. Destination (sip:*****@gw1.fonet.dk:5060) is not reachable, DNS error resolving FQDN, or service is not available.

If i register the same account directly on IP Phone, it gives no error at all, which gives me a conclusion there is nothing wrong with router settings neither the ISP, account registration fails only from 3CX Management Console.

Please help on it.

Regards,
Adnan.

 

[Kevin Attard Compagno]

@adnanj85

A Wireshark Capture would help you to understand if the PBX makes a DNS resolution that fails, of if the PBX makes a REGISTER request to the provider that is ignored or refused in some way.

 

[leejor]

You could try changing a few settings (depending on how you have it set-up currently) to try to pinpoint the problem.

Many people simply use their router as a DNS relay, the router usually defaulting to a couple of DNS servers "handed out" by their provider.

You could try putting the DNS server information into the server/PC running 3CX rather than relaying through the router.

You could try using another DNS server. A quick search on the net will give you some to try out.
http://pcsupport.about.com/od/tipstricks/a/free-public-dns-servers.htm

Google also provides a couple, 8.8.8.8 and 8.8.4.4

Make note of current settings before changing anything, then, make a change and see if there is an improvement, if not, change it back and move onto something else.

 

[Kevin Attard Compagno]

@adnanj85

This is the sort of issue for which 3CX Support exists