Voip trunks not resolving by DNS on 16.5

[ygonzales]

Dear All,
After update to 3CX 16 update 5 version .612

Trunks stop registering with error - 3cx registration postponed until target's destination is resolved
We also have applied Hotfix version .619

But the error remains the same

(We did update as usual, also we are thinking to create a backup, uninstall and reinstall the latest version with restore from a backup, but as this takes time we did not touch system yet)

 

[Saqqara]

On the machine, does the SIP provider DNS resolves to the correct IP.

Have you tried using IP instead of dns

 

[ygonzales]

IP works fine, nslookup resolves address correctly.
I have tried to change 8.8.8.8 to 4.2.2.2 but the same result

Also to check DNS in 3CX i have set IP is dynamic... and than 2nd error pop up:
Stun servers can not be resolved

Seems like 3CX nerver gets DNS reply back

Update: Roll back to 16 Update 4 fixed issue (we restore from a backup VM machine it self)
After we tried to try again update to 16 U5 but the same error occurs

 

[JohnS_3CX]

If you run a capture do you see a DNS reply back? and what does it contain?

The reply is not just an IP, there are other parts too which must receive a reply

- NAPTR
- SRV
- AAAA
- A