• V20: 3CX Re-engineered. Get V20 for increased security, better call management, a new admin console and Windows softphone. Learn More.

Solved iOS IPv6 T-Mobile

Status
Not open for further replies.

AJT

Joined
Jun 1, 2017
Messages
3
Reaction score
0
Hello,

We are seeing issues with the 3CX app not registering when on the IPv6 T-Mobile cellular network. I know a lot of work has been done on this already, but for us it is not working. Our 3CX server is hosted externally.

When an iOS device is on a Wi-Fi connection, the 3CX app works fine. When we are on T-Mobile LTE / 4G, the presence is detected, but the SIP registration fails. If I connect an iOS device to another iOS device via Personal Hotspot, the IPv6 symbol in the app does not appear, and the SIP registration is successful. It's only an issue when IPv6 is detected.

Our 3CX server does not have an IPv6 address, and we have no IPv6 information in any of our DNS records.

Not sure if other people are seeing this issue or not, and if anyone from 3CX is able to troubleshoot?

I don't have access to devices that are not on T-Mobile, so I am unable to test if the issue occurs on Verizon, AT&T etc.

Our 3CX server is running 15.0.62928.5 and the iOS app is 15.2.6.194.

Device Info
-------------------------------------------------------
Phone Model: iPhone
Generation: 7 Plus
Firmware Version: 10.3.2
Jailbreak: No
Cydia Installed: No

Issue Info
-------------------------------------------------------
Handset: Phone
Contacts: Local
Connection: 3G / 4G / LTE
Server: External
 
Hi
Is your PBX has its SIP port (usually 5060) opened?
To check this, from an "out-of-office" location try a telnet to its public FQDN : port.
 
Hello Vali,

Yes, 5060 is open on our firewall. We know this because as I mentioned, the app works fine on Wi-Fi connections including public ones such as airports / coffee shops etc. We do use the tunnel on 5090 as well.

It's specifically on the T-Mobile LTE network when the app detects IPv6 and shows the IPv6 icon, that we are unable to get a SIP registration.
 
OK, check your PM tomorrow, when I will be at work I will send one, now here it's well past midnight :D
Don't worry, we'll fix it.
Regards
vali
 
OK, we checked - problem solved, port 5060 was closed.
 
Thank you Vali for your assistance getting this fixed. I can confirm everything is now working as expected. We were not aware that 5060 needs to be open to the world for it to work on the T-Mobile IPv6 network. I assumed the tunnel would still be used, so we had 5090 open but 5060 was restricted. Hopefully this helps someone else in the future.
 
Hi
Is your PBX has its SIP port (usually 5060) opened?
To check this, from an "out-of-office" location try a telnet to its public FQDN : port.
i am having the same problem after i upgraded to the beta version. on my phone it shows ipv6 on t mobile. i used a port tester and it shows 5060 as being open. i have mapped the ports to my server and still do not get audio working on tmobile. but wifi works fine.
 
Last edited:
after i upgraded to the beta version
"beta version".... "Beta version" of what? PBX or client? Which version are both of them (as specified in their About page)?
 
"beta version".... "Beta version" of what? PBX or client? Which version are both of them (as specified in their About page)?
3cx beta 15.5.1694 ios client 15.2.6.194
 
If phone registers OK but there is no audio, then on the Management Console open your extension page and there enable "PBX deliver audio", press OK then try again a call (you may also test the echo service, *777) and see if it's working OK.
 
If phone registers OK but there is no audio, then on the Management Console open your extension page and there enable "PBX deliver audio", press OK then try again a call (you may also test the echo service, *777) and see if it's working OK.

just tried enabling pbx deliver audio. Seems to me that it just doesn't connect. When receiving calls from another extension in cell network, the app gets an alert but there is no audio. When trying to call another extension or a number, it seems that it doesn't connect to the system. I checked the logs and it shows the following.
 

Attachments

  • IMG_0214.PNG
    IMG_0214.PNG
    288 KB · Views: 9
  • IMG_0215.PNG
    IMG_0215.PNG
    275.8 KB · Views: 6
This is what the app looks like when dialing an extension on LTE. It never connects.
 

Attachments

  • IMG_0216.PNG
    IMG_0216.PNG
    388 KB · Views: 14
Any response? or should i just reinstall the whole system again?
 
Please send me by PM an eMail address to contact you, let's try to do some debugging.
Regards
vali
 
Hi, We are having same issue with user from TMobile using IPv6. It is mandatory to enable 5060 port in this scenario?
We are using 5090 to enable remote connections from Internet

Regards,
 
Hi, We are having same issue with user from TMobile using IPv6. It is mandatory to enable 5060 port in this scenario?
We are using 5090 to enable remote connections from Internet

Regards,

Yes, that is what we found. With 5060 blocked I could not use the 3CX app when connected to T-Mobile via IPv6. It worked OK on other cellular networks, but according to Vali from 3CX, the Tunnel app does not support IPv6 correctly yet, so you have to have 5060 open.

I tried to get T-Mobile to let me know what IP ranges they would be using, but I failed to get the message through to someone who could give me a sensible answer. You may have more luck. If you do, please post them so others can benefit.
 
Hi jhonku, andrew

To avoid confusion:
PBX should open its SIP port for TCP. By default, this is 5060, but if has been reconfigured as, let's say, 55060, then this should be open, not 5060.

Hope it helps
vali
 
Last edited:
In all our installations (+50), we only open ports 5090 (TCP/UDP) and 5001 (TCP) from Internet and avoid to use SIP port (5060) trying to reduce known attacks on this port.
Vali, we can change this default port, but we loose 3CX tunnel advantages.
Using 5090 attackers need tunnel password before register on PBX.

To clarify, 3CX Tunnel on iOS is compatible with IPv6?
 
I understand now. Well, I mentioned some time ago:

the tunnel - overall - does not support IPv6: clients tunnels, PBX tunnel, bridges, SBC, whatever; obviously, we have in plan (and we will have to, definitely) to do this, but it's not a trivial task.

Maybe is an (elegant) solution to change PBX SIP port without affecting tunnel functionality, but I'm one of the least person to advice you on this, definitely you need one from somebody skilled, either from community or from our tech support.
 
Thanks Vali, Andrew,
Now IPhone register correctly, but I realised that we need to open RTP ports for audio. :(
That is another advantage of 3CX tunnel
 
Status
Not open for further replies.

Getting Started - Admin

Latest Posts

Forum statistics

Threads
141,405
Messages
747,492
Members
144,370
Latest member
Imperial Treasure
Get 3CX - Absolutely Free!

Link up your team and customers Phone System Live Chat Video Conferencing

Hosted or Self-managed. Up to 10 users free forever. No credit card. Try risk free.

3CX
A 3CX Account with that email already exists. You will be redirected to the Customer Portal to sign in or reset your password if you've forgotten it.