3CX and Phone on PublicIP - not work

[ivan.iph]

We have 3CX server on PublicIP without firewall and remote phone with another PublicIP without firewall too. The problem it can not register. In 3CX logs noting about that. Via Wireshark I see SIP packets from phone IP, but 3CX do not answer to it. What can I check?

 

[leejor]

Please post the log of the registration attempt. Verbose mode will give you a lot more information. You can X out part of the public IP for security reasons.

 

[bardissi]

This can be tricky as if you are using the 3CX phone provisioning templates to setup the remote phones the templates by default need to be modified to use the correct IP address in the phone template.

Also, you would need to port forward the correct ranges of udp / tcp ports for each extension.

The "supported" 3CX method is to use the 3CX tunnel app or VPN.

You could bypass a lot of this headache by using a Session Border Controller.

We offer a hosted SBC that re-writes the packet headers of the remote phone traffic so that you wont need to use VPN / Tunnel and do not have to jump through hoops to do all this routing through many port forwards and firewall changes.

Let me know if you want to test it out and we can set you up for a trial.

 

[ian.watts]

May want to check the bindings with NETSTAT.. 5060 UDP should be listening on the PublicIP you want:

Mine is behind a firewall here.. LAN IP is 10.10.10.10..


UDP 10.10.10.10:5060 *:*
UDP 127.0.0.1:5060 *:*
UDP [::1]:5060 *:*
UDP [fe80::5efe:10.10.10.10%14]:5060 *:*
UDP [fe80::8530:6c7c:cd9f:60a1%12]:5060 *:*

3CXPhoneSystem.exe is the process listening on these addresses.
Last.. what about Windows Firewall?..

 

[leejor]

Also, you would need to port forward the correct ranges of udp / tcp ports for each extension.

Why?

They have stated that they are using a public IP at each end, so I'm assuming that there are no routers involved.

 

[bardissi]

There is always nat occurring on one side or another...It looks like the phone may be behind nat where the 3cx may have a public ip

 

[leejor]

There is always nat occurring on one side or another...It looks like the phone may be behind nat where the 3cx may have a public ip

Well since they haven't bothered posting any more details, that's simply a guess at this point.

 

[craigreilly]

Allow connections outside of the LAN ?