Fanvil X5U as Local Phone - SIP Register Failed

[DYHLYU]

Please see picture for error message. I'm getting this constantly, multiple times a day but it's completely random. Sometimes a few phone will go down, sometimes all, but the Web client / SBC + Grandstream HT802 has no problem at all.
I checked the Event Log but couldn't find anything useful. This is the Event Log for today, but my ext 12 is down as of now.


This only started to happen after the V20 upgrade, I have not changed any provisioning method. FYI I did try to "Delete Phone", "Reset Phone to Factory" and then "Reprovision" but it didn't help.

The voice provider is Flowroute, I also made sure that the IP address for 3CX cloud server is on the whitelist of

Any help is appreciated, I'm not sure what I missed.

 

[Fanvil Technical Support]

Hello @DYHLYU When X5U prompts that SIP registration failed, please enter the X5U web console and check the Line Status. See the attached file.

 

[JohnS_3CX]

That icon that appears in the corner up there, I think this is the broadcast storm detection which could lead to denial of service.

Basically the network is so overloaded that the phone cannot communicate with the server.

 

[DYHLYU]

Thank you both. I've finally obtained the device log while it's happening.
Please see attached.

I did check with my other locations, this lightning icon does not show up. Maybe that is the reason but I'm trying to figure out how to identify the cause.

 

[DYHLYU]

Now I just switched this phone to be behind a SBC and also manually registered. Waiting to see how it goes.