Fanvil X4U Line status timeout stun:true

[ihall]

firmware is 2.4.12 on all phones. Cloud PBX is on 18.6. this system has been on the cloud PBX since August 2022 with no problems until this week.
I am having an odd issue with a few Fanvil X4u phones. A customer with 6 phones had a prolonged Internet outage. When the Internet came back none of the phones would register with 3cx cloud hosted PBX. I found that their external IP address was black listed. I removed it from the black list and 1 of the 6 phones registered. All the other had the timeout stun:true on the fanvil SIP line.
Also seeing this message in the 3cx even log when the phones are trying to register
Provisioning file /provisioning/xzxzxzxzxz/firmware/fanvil/version.txt requested by ###.###.#.# could not be generated (masked IP and file name)
3CX Template Parser ID: 30040 03/08/2023 9:30:23 PM
I tried the following
1. rebooting all phones. one more of the six registered and 2 total were working.
2. resetting and auto provisioning all phones with the correct information from the PBX. 2 more registered. 4 our of the 6 are now working.
3. reviewed extensions for special characters in BLF and name.
Any thoughts on this? Thanks.

 

[SweetAction]

Are these phones provisioned with STUN? While it can work, it's far more preferred to use a SBC to prevent these issues.

If these phones are X4U-V2's you can even use the phone as a "RouterPhone" where it runs the SBC on the phone itself.

 

[JohnS_3CX]

Hi,

Any thoughts on this? Thanks.

The only recommendation we can offer for this very specific type of issue is to install an SBC at the premises where the phones are. When the internet comes back, they will all register again.

However, the internet outage does not justify why the office IP was blacklisted. This is something you should investigate further.

The provisioning file error you saw can be completely and safely ignored - it's not in any way or form related (just a typical informational message for something that does not apply to 3CX systems).

Other than the internet outage you had, the behavior you saw is quite typical for STUN phones. They will work fine until something upsets their connection, and after that it a matter of luck. The SBC can remove the "luck" factor and replace it with the field-proven reliability you can expect from 3CX. In case there is any doubt, we strongly advise you to avoid STUN and we do not provide support for it on "Hosted by 3CX" systems ourselves.
https://www.3cx.com/docs/3cx-tunnel-session-border-controller/

If these phones are X4U-V2's you can even use the phone as a "RouterPhone" where it runs the SBC on the phone itself.

I'm afraid not, judging from the firmware version these are Revision A devices so they cannot act as router phones. They will need to install a SBC machine or replace one of their phones with a newer generation device.


Let me know if you have any questions or need clarifications.

 

[ihall]

The phones are setup for STUN. Thanks for the feedback and clear direction. I will look at setting up an SBC over the weekend. I will update this after SBC config.

 

[JohnS_3CX]

Sure thing, let us know if you have any questions or difficulties and we will be glad to help!