Solved 3cx Cloud with SBC

[halter_joel]

I am trying to setup Remote extension on my AWS Cloud based 3cx. I can not get the phones to show up under the phones tab going thru the SBC.
Here is my setup
3cx Standard Version 16.0.676
Yealink T29G with firmware 46.80.0.130
Raspberry PI 3b+ Connection to PBX is connected under Sip Trunks
Firewall on remote side has port 5000, 5001, 5090 open

I can get the phones to register to the pbx if i manually put in the Information, but i want to be able to have the phone show up under phones tab and configure it to the extension. I've read that if the phone is in the same network as the SBC the sbc should pass the info to the 3cx PBX. Am i wrong on that?

 

[CentrexJ]

The phone firmware is old and should be updated but they likely should still be showing up to be configured. They may however not take the configuration if the firmware is that old but you will find out once you get to that spot.

Were the phones turned on before the SBC was online? If so restart or factory reset the phones Also make sure not only that they are on the same network but same vlan as well.

 

[halter_joel]

Ok so i've upgraded the phone to the correct version thru 3cx website. The SBC was installed and connected before the phone was plugged in. Also there is no VLan in this network setup. Router, Raspberry PI, and Phone is what the network consist off (BASIC). With the new firmware it still doesn't show the Phone. I also have tried a Yealink T26P to see if it would act any different and it did not. I've read alot of articles about the SBC but is there and article that explains how the SBC works in the background. How does it know there is a phone that it needs to communicate with?

 

[hogan71088]

Is all traffic allowed outbound from the sbc?

 

[halter_joel]

Is all traffic allowed outbound from the sbc? Allowed through the firewall?

 

[cobaltit]

Firewall on remote side has port 5000, 5001, 5090 open

What does this mean? If the remote side = phone side you don't you most likely don't need to open any ports. All communication is outbound and most firewalls by default only block incoming traffic. Factory reset the phones and they should PnP properly and show up. Try that and let us know.

 

[JohnS_3CX]

Hi Joel,

As recommended above by the other members, ensure your device firmware is updated before you do anything else. This guide will help you https://www.3cx.com/sip-phones/yealink-t20p-t22p-t26p-t28p/

Then, reset the phone and when it comes up again it should appear in bold in your Phones tab.

 

[halter_joel]

Good Morning All, Yes on my router i have all those ports open. I understand that i shouldn't have to open them but sense it wasn't working and the Document that i was reading said to do so. I first tried it without touching the Firewall with no success. @JohnS_3CX as stated in post 3 I have upgraded the phone and Factory Reset it probably 10 times now. Is it possible that the Router that i'm using isn't allowing PNP.

 

[Evolute IT]

Good Morning All, Yes on my router i have all those ports open. I understand that i shouldn't have to open them but sense it wasn't working and the Document that i was reading said to do so. I first tried it without touching the Firewall with no success. @JohnS_3CX as stated in post 3 I have upgraded the phone and Factory Reset it probably 10 times now. Is it possible that the Router that i'm using isn't allowing PNP.

What's the router?

And whatever document you read, it was wrong. When using the SBC, the remote-side doesn't need port forwarding, only the PBX side.

 

[halter_joel]

The Router is a Calix 844E which is what our ISP gives out. I've also tried a Asus RT-N66U.
Here is the Link to the Document i was reading
https://www.3cx.com/docs/3cx-tunnel-session-border-controller/#h.9yi5hq9vpsyu

 

[halter_joel]

Well I just Rebooted both phones when connected to the Asus Router and Both phones popped up under the Phones List. So it seems like the Calix Router that our ISP uses isn't passing any of the UPnP packets to the rest of the Network. Even though there is a setting in the Router that says UPNP and its Enabled.

 

[cobaltit]

Step 1 – Configure the Firewall
The tunnel protocol is designed to eliminate NAT traversal problems and reduce firewall configuration work to a minimum. There is only one Firewall setting that needs to be made – we must forward the TCP and UDP tunnel port (set by default to 5090) to the PBX.

I think you were misinterpreting that step. As it says, you only need to forward the port to the PBX which would be the AWS side, not the remote/phone side.

Well I just Rebooted both phones when connected to the Asus Router and Both phones popped up under the Phones List. So it seems like the Calix Router that our ISP uses isn't passing any of the UPnP packets to the rest of the Network. Even though there is a setting in the Router that says UPNP and its Enabled.

You are mixing things up. UPnP and SIP PnP are two different things and are unrelated. UPnP means the router listens to requests to dynamically create port forwards in the router. SIP PnP is when the SIP client starts up it sends subscribes to a multicast address which the PBX or SBC listens to. That's what allows it to show up in the console. Because the SBC is relaying that through the tunnel there really isn't anything your firewall can do to stop it if it's allowing the outbound tunnel traffic. I suppose if you only have a handful of devices and the SBC and phones were plugged directly into the Calix router and the Calix router was configured to block multicast that could be an issue, but if both the SBC and phones were on their own switch downstream from the Calix it shouldn't matter.

 

[JohnS_3CX]

What @cobaltit said. Multicast will not reach anyone if your router blocks it (which is most likely the case).

Changing the router allowed the multicast Subscribe message that a reset phone sends to reach the SBC.

Then the SBC sent that info to your management console (it appeared with an IP, model and MAC - the stuff you need to provision it basically).

Then the PBX can send the Notify message directly to the phone (using the SBC to relay that message) to tell the the phone to go provisioning itself from X address and the rest takes place on the phone.

The failure was that the initial multicast subscribe was being stopped most likely by your router, and the rest is self explanatory now

 

[halter_joel]

After going through the router Config i did find a setting under IGMP that had a checkbox that was unchecked Labled IntraLan Multicast Enabled. I checked it rebooted router and then rebooted phones and it worked.
Problem Solved thank you everyone for there great knowledge!!!!

 

[JohnS_3CX]

Ah excellent, at least it gives you the choice to enable it, glad to hear it was resolved