Yealink phones - Unable to provision or autoprovision

[dytech]

I am having trouble getting my Yealink handsets to provision. I have tried several different models of handset with the same result. The autoprovision always fails. The 3CX server is located in a private datacenter. The offices are connected through VPN tunnels. All networks are connected using Sonicwall branch office vpn tunnels and all computers and other functions work perfectly. I can ping the 3CX server from the phone.

The phones do not popup for PNP configuration. That is probably due to the WAN configuration. The server does not autodetect the phone. I am manually pasting in the provisioning link. i.e. "http://69.28.89.250:5000/provisioning/1vldsi1prb". The phone just does not provision.

I do have functioning telephones on this setup. I am able to get a telephone to work by manually configuring the extension, sip server, ID and password. Anyone have any ideas?

 

[Evolute IT]

The phones do not popup for PNP configuration. That is probably due to the WAN configuration.

This is actually due to multicast rarely working over VPNs.

I am manually pasting in the provisioning link. i.e. "http://69.28.89.250:5000/provisioning/1vldsi1prb". The phone just does not provision.

Is that the public IP or the private IP through the VPN? If my memory serves, the HTTP port can only be accessed via RFC private networks (192.168.0.0/16, and such.)

 

[Saqqara]

As above, handsets will not appear to multicast not working over the vpn.

Use the provisioning url displayed management console after you have configured one of the phones

Add the phones to 3cx manually (configure as lan) and use dhcp o-toon 66 https://www.3cx.com/sip-phones/DHCP-option-66/

 

[JohnS_3CX]

Hi @dytech

For 3CX to work correctly using VPN, you need to make sure that both the system and the phones are blissfully unaware of the VPN - it needs to be practically transparent (aka Layer 2 VPN).

They need to think that they are all on the same local network, within the same subnet. You also need to be able to pass multicast messages between the two sides otherwise the phones will never appear as "new" in your management console.

Also be careful of what IP range you use - 3CX requires that the IPs are compliant with RFC 1918 address space for both the phones, and the PBX to be able to work in "Local network" mode.

I think your issues all come down to networking, as we have seen this type of issue enough times with VPNs to hold this as the primary suspect. I'm afraid the fact that you can ping only means that you can ping - and nothing more. Once done correctly though, the VPN should work just fine and you should not really have much to worry about.

Note: Option 66 might not work at all in this case, since manually inputting the URL did not yield any results.