3CX Firewall issues since v18.5

[TechnicianHPP]

Since upgrading to 3XC V18.5 we have firewall issues being reported. I have contacted our firewall company and managed to solve a range of port issues but I have been left with 3 issues that cant be solved at the moment.

testing 3CX PhoneSystem 01 SIP Server... failed (How to resolve?)

• stopping service... done
• detecting SIP ALG... failed (How to resolve?)
• testing port 5060... full cone test failed (How to resolve?)

3CX gives me this website - https://www.3cx.com/docs/firewall-checker/

The firewall company have said they have turned off SIP ALG on teh firewall and port 5060 is open inbound and outbound but still failing. Anybody got any ideas?

 

[SteveITS]

SIP ALG is a firewall issue, it wouldn't have changed with a 3CX update. What model firewall is it? Is there another router, such as an ISP router, in the chain?

 

[TechnicianHPP]

We have a juniper firewall, hosted by RM Education. They have said it is turned off at the router.

 

[TechnicianHPP]

After 3 hrs with the firewall company yesterday we have got down to two errors

• testing 3CX PhoneSystem 01 SIP Server... failed (How to resolve?)
  • stopping service... done
  • detecting SIP ALG... failed (How to resolve?)
  • testing port 5060... done
  • starting service... done

Upon checking we could see the firewall rules are already in place with SIP AG disabled.

 

[SteveITS]

So the wire from the ISP connects directly to the Juniper? Maybe a bug in that router?

Did your team read through the link provided, https://www.3cx.com/docs/firewall-checker/#h.ikh44hto4r56 ? If something's altering the packets it's a matter of figuring out what that is.

 

[TechnicianHPP]

Thank you ill check with them but they have said they have check all the document