V15.5.346.651 - No Tunnel + WiFi *OR* Tunnel + 4G

[KF-Dale]

Phone Model: OnePlus 5T (Firmware: Android 9 & OxygenOS 9.0.4)
App Version: 15.5.346.651
Connection: Both
Server: 50/50 (Internal but on a separate network to my 3CX Windows client & the phone over WiFi) - PBX Version: 15.5.15502

Connectivity using the app is very inconsistent, I often get problems whereby it does not establish a connection to the PBX meaning I cannot make or receive calls. I have also noticed the connectivity issues will go away at least over 4G if I turn off the 3CX Tunnel, but this leads me to the issue where if I turn off the tunnel then close the app, upon reopening it the tunnel is re-enabled, for some reason it does not save on the account that I have turned it off.

I do use the 3CX Client for Windows but I am on a separate network to the PBX, but if I connect my phone via WiFi I am on the same network as the Phone with the 3CX client.

Explained in another way, I am never on the same network as the PBX, but I can potentially be on the same network for the 3CX Windows Client and the Mobile Phone App.

Here is a table of the combinations:

WiFi/4G	Tunnel	Works?
WiFi	YES	YES
WiFi	NO	NO - "Waiting for network"
4G	YES	NO - "Waiting for network" & "Register failed, timeout"
4G	NO	YES

 

[KF-Dale]

Having had the opportunity as a temporary test, I connected my phone to the WiFi network that is connected to the PBX, if the Tunnel was OFF then I get the same situation as described above.

It is also worth noting, that I am the only person to use an Android device on this PBX, though the app is used regularly it is always on the iOS version.

 

[YiannisH_3CX]

Hello @KF-Dale

From the description is looks like you are never local to the PBX and the client will always try to use the tunnel to connect. The tunnel requires port 5090 to work so make sure that that is open on your firewall. You can try to run the firewall checker to confirm everything is working properly.
Also have you tried a different Android device to see if the issue remains?
Also you can turn the tunnel off from the extension settings through the management console although i would not recommend doing so.

 

[KF-Dale]

Hi @YiannisH_3CX

That is correct, in my normal course of use I am never local to the PBX.

When I disable the Tunnel in the account everything works fine, the issue is with the fact that the app does not save this setting state - so when re-opening the app the tunnel is back on. Unfortunately, I only have the one device available for me to test this with.

The PBX has all related ports forwarded correctly, and the firewall test on the control panel passes all checks. The primary person responsible for managing this PBX does not want the Tunnel turned off.

 

[YiannisH_3CX]

When tunnel is disabled (not advised) the client will try to contact the PBX on port 5060. With tunnel enabled the client will try to contact the PBX on port 5090 so from your description i would assume that that is where the issue is. The admin of the PBX is right to want the tunnel enabled as the clients are not STUN aware, meaning that you might encounter cases where the client cannot contact the PBX and tunnel also helps with NAT traversal as all traffic is routed through one port.

 

[KF-Dale]

Hi @YiannisH_3CX
The weird part I don't follow though, is that having the Tunnel enabled on WiFi allows it to work, but having it enabled on 4G causes it to not work. Refer to table in original post for the combinations of what does or does not work.

Based on what you said there, even more oddly, the app works fine with 4G and Tunnel off... it's just the setting is not saved on the profile in the app, so if I close the app the next time it opens then the Tunnel is back on... that's unless it's a visual thing and the app is in fact using the tunnel anyway?

EDIT: Also, for clarity, the admin of the PBX does not force Tunnel connections for me, he allows me to disable the tunnel in the app. He just doesn't want to turn off the tunnel completely on the PBX itself.

 

[JohnS_3CX]

@KF-Dale the new version 16.0.0.35 is out. Please check it out and let us know if you have any improvement.

 

[KF-Dale]

@JohnS_3CX Having used it for a few days it does seem to be behaving itself more, particularly when I am on 4G. I will continue to use and report back when I have used it a bit more. Please pass on my thanks though!

The only thing I did notice is that my setting for "Use 3CXTunnel when Out of office" on my Account is still not remembered if I close the app (this includes swiping it away on the app list).

 

[JohnS_3CX]

You can change it permanently from the management console under your extension's 3CX Client Provisioning

 

[KF-Dale]

Hi @JohnS_3CX - thanks for this info, currently I'm going to leave it on, and that's overall where I get the best behaviour. Of course when working properly it does as intended to allow the app to work behind NAT/Firewall.