Handset vs Softphone firewall configuration

[dxcza]

Hi all,

Got a bit of a tricky situation here.

We have Fanvil handsets in the office as well as users who use the application/web app on their phones and laptops.

The Fanvil handsets have no issues dialing out or receiving calls. However, users utilizing the app's have issues, chief among which is that only ever 2nd or 3rd attempt, a call is going through.

Could this be a firewall issue?

The 3CX server sits on the Internet. The office sits behind a Mikrotik router which is doing the NAT.

Any other guidance would be greatly appreciated.

 

[eddv123]

This is an outline of the ports required for 3CX: https://www.3cx.com/docs/ports/

Although I do not think this is a firewall issue as the call eventually establishes. The only firewall functionality which would affect this would be SIP ALG which probably would affect both types of phone/traffic.

Have you run the firewall however - do you get a successful result ?

The only other differentiator would be VLAN's (local network) if your network is split your phones would reside on the voice VLAN where App's (if browser or Windows/MAC) would reside on the Data side.

Do the local PC's running the Apps have Windows firewall/Defender or Antivirus running on them ?

 

[YiannisH_3CX]

Hello @dxcza

Please make sure that the clients are configured to use the tunnel. You can do so from the management console, extension settings / Phone provisioning. Choose the 3CX client from the drop down menu and make sure that the tunnel is enabled. Make sure you re-provision the clients to apply the changes. Also check the activity log of the PBX for any logs that might indicate why the calls are failing. You could also see if the calls are actually reaching the PBX.