Connect remote Snom 300 to 3CX via VPN?

[acnsuk]

I have the following set up:

-Installation of 3CX V8 in our main office on Server 2008. (IP address range : 192.168.89.xxx with 3CX on IP 192.168.89.2)
-VPN is set up on server 2008
-A home office connected to the internet with ADSL and can connect to main office via VPN (IP address range 192.168.0.xxx)

If I install the 3CX soft phone on a remote PC, connected to the home office network, it connects and works with 3CX well.

I want however, to use a SNOM 300 instead of the softphone.

I have the SNOM 300 connected into the home office router/ADSL modem and a PC 'daisy chained' with it, so the PC can still connect to the router / internet as normal. The VPN is connected and working on this PC. The SNOM has DHCP set 'on' and picks up an IP address in the range 192.168.0.xxx from the home office router. I have set the 3CX IP address to 192.168.89.2 in the SNOM interface.

Can someone assist with what settings I need to make in the web interface to connect to the main office 3CX installation?

Thanks

 

[discovery1]

Just because the PC is daisy chained through the Snom does not mean that the Snom uses the VPN from the PC.
The only way to get the Snom to use a VPN is if it is connected from your router to your office, not from the PC to the office.

At the moment the Snom is trying to connect over the internet which is possible, but you need to open the correct ports on the office firewall and forward them to the 3CX machine.

On the Snom you set the SIP settings up with the registrar and the proxy having the external IP of the office firewall and then change the following settings on the Snom

SIP ID 1 > NAT tab
stun server = stun.3cx.com
STUN interval (seconds) = 300
Keepalive interval (seconds) = 20

SIP ID 1 > RTP tab
Symmetrical RTP = on
RTP Encryption = off

 

[acnsuk]

Thanks.

I'll try that.

Which ports? 5060 I assume? Any others?

 

[leejor]

If the VPN server at the office end is using PPTP you could install a router with the DD-WRT VPN firmware load at the remote end. You would then have a permanent VPN connection with all devices at the remote end. VPN requires a server and a client. I don't think the SNOM or most other VoIP phones will act a a VPN client on their own, so something at the remote end would have to do that part for it.

Which ports? 5060 I assume? Any others?

5060 is usually the default port when there is one device at the remote end, then just start counting up for each additional device using a single public IP behind a router.

 

[acnsuk]

This almost works now.

The remote phone registers and I can dial in to the main office.

Dialling this remote extension from the main office, rings the remote phone but picking it up, neither party can hear each other.

If you hang up the call generated from the main office, the remote phone continues to ring??

Any pointers appreciated.

 

[LeonidasG_3CX]

Hey acnsuk,

Just to give you some info on something, were are going to release a new version of the Sip Proxy Manager soon that will include a few bugfixes.
With the 3CX Sip Proxy manager you will be able to connect all your phones remotely to your PBX anywhere.

Just give it a week or two and you will have it

 

[acnsuk]

Are you saying the behaviour I am seeing is a bug?

 

[[email protected]]

Did you use a gateway like patton?
The 3CX provisioning file not includes the default gateway to your vpn-router. you must set it manually.

 

[acnsuk]

No, there is no gatwway.

 

[dapatter]

Hi I have this exact same problem, snom registers, can dial, but then there is no sound / rtp....any ideas?

 

[leejor]

No audio = blocked or misdirected ports. If there is no audio at the remote set, check the router at that end and determine why the RTP packets can't reach the set. Be sure you have STUN enabled on the set.

 

[dapatter]

Hi done that, but what about this?

http://www.3cx.com/forums/sip-proxy-for-snom-external-extension-with-static-ip-14688.html

what is the actual problem with Remote SNOM's not been able to register with 3CX?

btw I tried this sip proxy server and it didnt work.

 

[pcunite]

This is what a Snom 370 is good for, it has its own VPN client.

 

[dapatter]

Has anyone got any more information on what the exact problem is here?

 

[StefanW]

SNOM does not work as a remote ext at the moment. It send the data to a wrong address in the SIP Stack.
There is the first fix to it in FW 8.4.9 to send the Packets right but the first register of the phone is not using stun. you have to go after you restarted you phone to the Identity 1 and click on re-register and then the phone will use STUN to register against the server.

have you stun enabled at all on your snom 300?
Other option is to use the 3CX sip proxy manager. in that case you dont need stun and not nat but your PC must run at all time due to it is the gateway to the server..

 

[dapatter]

I cant see the 8.4.49 firmware on the snom site, latest is 8.2.29?

 

[StefanW]

http://dms.snom.com/mydms/out/out.Login.php?referuri=/mydms/out/out.ViewFolder.php%3Ffolderid%3D440

beta
beta

 

[dapatter]

all working, thank you.

 

[dapatter]

just an update....this seems to only work intermittently. I am also getting constant call disconnects after 30 seconds. do you know whether snom have done any more work on this, otherwise i am probably going to get a grandstream phone.

 

[rmm]

I’ve just stumbled across this post as I’m having an issue with my remote SNOMs provisioning the Company Phonebook.

I do have a remote SNOM 300, connected via VPN, which has been working fine, without STUN settings (I also turned STUN off on the 3CX as we’ve a fixed IP for our VOIP Provider) in the configuration acnsuk describes. I use Draytek routers at each site (which also manage the VPN connectivity).

I did, however, connect a another SNOM 300 at another VPN remote site and while that too worked fine back to H/O, there was no audio between calls to the two remote sites. I posted this (http://www.3cx.com/forums/external-extension-to-external-extension-no-audio-15113.html) regarding it but have yet to look into it further. Although, making a call from the remote site via 3CX Phone to the other remote site’s SNOM 300 worked fine with audio. Only difference I can see there is that the 3XC Phone did have the STUN server settings set.

Based on my initial success with the remote SNOM 300, I was going to roll out another remote VPN site with two SNOM 320 phones (I use SNOM exclusively). Now I’m a little worried after reading the comments here from StefanW...