Troubleshoot Handset Random Re-Registration

[Robert Hefner]

Hello,

Running into issues with Snom D785 handsets periodically re-registering with 3CX server. Phone are set to local LAN for Provisioning Method. This also happens to phones set to STUN but with higher frequency. The display will be dim on the phone then light up when the phone is going through re-registration process. This only appears briefly and I have never experienced it while on an active call but this feels like odd behavior to me.



Has anyone ran into this issue or possibly shed some light on this?

 

[AWS2P]

if you speak about automatic provisioning each 24h then this is by design on 3CX, most of the time this is when we are not near phones to see them doing provisioning.

On mine have seen complete reboot being done alone randomly so this is not normal design.

 

[Robert Hefner]

The handsets do not reboot rather they just re-provision. And it is more often than every 24 hours. Does anyone else have this issue?

 

[eddv123]

Phone are set to local LAN for Provisioning Method

I would assume although not specified (as you mentioned using STUN also) that for local LAN you are using an IPSec VPN tunnel to hosted cloud system ?

STUN I would not even attempt for multiple phones (2 +) unless you have full control off the firewall and know how to port forward correctly (all ports required - see attached).

If you are using VPN tunnel however you need to look at either the phase 2 VPN settings (this is what controls the traffic flow across the VPN) and you could as a test provision a phone with SIP transport TCP instead of UDP, although the issue is still network related, I have seen more positive results from this transport type (TCP is a connection orientated transport protocol).

 

[Robert Hefner]

I would assume although not specified (as you mentioned using STUN also) that for local LAN you are using an IPSec VPN tunnel to hosted cloud system ?

STUN I would not even attempt for multiple phones (2 +) unless you have full control off the firewall and know how to port forward correctly (all ports required - see attached).

If you are using VPN tunnel however you need to look at either the phase 2 VPN settings (this is what controls the traffic flow across the VPN) and you could as a test provision a phone with SIP transport TCP instead of UDP, although the issue is still network related, I have seen more positive results from this transport type (TCP is a connection orientated transport protocol).

Correct the local LAN traffic is traversing IPSec tunnel. The moment I switched to this provisioning method the frequency of the re-provisioning dropped significantly.

I am running the 3cx server in a Debian 9 build. I have seen some previous posts in the forums about Debian 8 being a better distro for the 3cx platform however that could be a rabbit hole. I sure would be open to any possible solutions you folks might have for this as this behavior does not appear to be the default behavior of either the handset or the 3CX system.

 

[Robert Hefner]

Any 3CX SME's want to weigh in on this ongoing issue? I am still having random handset registrations.

 

[eddv123]

Any 3CX SME's want to weigh in on this ongoing issue? I am still having random handset registrations.

Have you looked at using TCP for SIP transport traffic yet ? this would be a slight alteration on a custom template - alternately the only other option (since it is a random occurrence) would be running a long-time capture on Wireshark.

This can be done either on 3CX using tcpdump https://stackoverflow.com/questions...-tcpdump-to-run-for-a-specific-period-of-time or a mirror port or network Tap to a machine or NAS drive.