Grandstream BT200 and GXP2000 external extension

[tsukraw]

Hey guys,
Wondering if anyone out there is still using BT200 and or GXP2000 phones.
Have a customer who had an old asterisk system usings these phones. The askerisk system died so we did a quick setup of 3CX which worked great for the internal phones.
We are however seeing an issue trying to setup external phones. We are able to get 1 phone online from a location and make/receive phone calls. But we are not able to get a second phone online. It will never register....

We have tried following the STUN/NAT settings on the following URL but when we turn on NAT Traversal (STUN): and/or Use RFC3581 Symmetric Routing we are no longer able to get inbound audio only outbound audio.
http://www.3cx.com/blog/voip-howto/remote-extensions/

Does anyone have any advice or recommendations besides replacing the phones with a newer model. We are talking 200+ phones so a fairly large expense.

 

[bardissi]

Yes you can use a SBC (like the one we have hosted in the cloud) for the remote phones in the outbound proxy field.

This would remove the need for STUN / VPN / 3CX Proxy Manager and allow all of your phones to be remote to the server.

 

[complex1]

The phones on the same remote location must have different SIP and RTP ports.
You can use STUN (e.g. stun.sipgate.net) and make sure your port forwarding to the phones is correct set-up. Ensure SIP ALG is switched off in the router.
If you have to many phones located on one site then make use of the 3CX Proxy Manager.
I have a smaller set-up then you have, 10 external phones at one location, and all work perfect. No VPN, no 3CX Proxy Server, no SBC. Just connected directly via WAN to the 3CX Phone System as described in the 3CXblog How-to remote extensions.

 

[bardissi]

3cx proxy manager can't support more than 60 phones

Changing port numbers for that many phones isn't a real option

 

[tsukraw]

In the phone is a option for "Random Port" if i set that to yes will that cover the port being different per phone?

 

[bardissi]

No you would need to manually set different port ranges in 3cx for every extension manually and then port forward through the firewall

 

[tsukraw]

So does the posted remote extension with STUN not work any longer?
We are just trying to figure out the best process for getting all these remote phones online without replacing them all.

 

[bardissi]

Stun works for a few phones Max 10 but not for the qty you are talking about

Again the cleanest way is a session border controller

$25.00 a month should fix your issue

 

[complex1]

@ tsukraw,

Are you using 200+ phones at one location or are they spread over different locations?

 

[complex1]

3cx proxy manager can't support more than 60 phones

From which source comes this info from?

 

[tsukraw]

the 200 some phones are spread amount multiple locations. No more then 20 phones in one location.

 

[bardissi]

That information came directly from 3CX support

As far as 20 extensions per location STUN is not an option for you.
1.You could use a Windows Machine for the 3CX proxy at each location (if this machine goes down so does your phones)
2. You could setup a vpn via your firewall back to the central server at each site (painful and a lot of overhead traffic due to VPN)
3. You could try to setup up different port ranges for each phone at each site and do a LOT of port forwarding (also painful)
4. You could try a hardware based SBC at each site (another device to manage and $$$ spent)
5. You could use a SBC cloud based as a service

 

[tsukraw]

So we just did some testing and i seem to be getting conflicting information on here compared to what we are seeing.
We turned off stun on the phones. When we did this we could only get 1 phone at a location to register the other phones would just sit there not registering.... As soon as we turned on the option for "User Random Port" We were able to get multiple phones registered and were able to make/receive calls multiple calls from different phones at one time. So it appears that we indeed have this working.

The only other thing we had to was was check the box "BPX delivers audio" per extension to get it to be able to call between locations.

We tested it from 3 different locations with multiple phones at each location and all 3 locations had the same successful results.

 

[complex1]

We tested it from 3 different locations with multiple phones at each location and all 3 locations had the same successful results.

Good to read you have succesfull results.
Keep up testing and let us now the final results.