Remote Extension behind SonicWall TZ150

[semtex65]

Hi Guys,

As the title would suggest, I'm trying to get a remote extension up and running at another office which runs a SonicWall TZ150. Now, the phone in question is a Snom 300. I've configured the phone, and can plug it into pretty much any router at any location and it registers with the server back at the main office, no problems, no config of the remote extension's router required.

Take this same phone to the office which has the SonicWall, and whilst the phone registers, there is no audio either way. I've added rules on the Sonicwall to allow RTP traffic through to the phone, but still, no audio. I would've thought no port forwarding would be required anyway, based on the fact that this works on any other router fine.

So the question would be, what do I need to configure on the SonicWall to allow audio through?

Cheers

 

[albertc]

What version of SonicOS you are running in your TZ150?

 

[semtex65]

Hi, its SonicOS Standard 3.1.2.5-96s

 

[albertc]

Alright. Try this. Login to the firewall admin page.

1, Remove any port forwarding that you did for making your phone to work.
2, Under the VOIP section, Enable Consistent NAT. And make sure the rest of the setting on that page (i.e. Enable Sip Transformation...etc) are UNCHECKED.
3, Reboot the firewall and that should do it. Also, update to a newer SonicOS if possible.

 

[semtex65]

Hi,

I've disabled all rules relating to VOIP/RTP traffic. Consistent NAT was already enabled, with no other settings active on that page, such as SIP Transformation. Rebooted, and still no audio. Any other ideas?

Thanks

 

[mylove4life]

it there any other outside phones working? might be the other firewall..

 

[albertc]

Try updating the SonicOS to a newer version. You can download a newer version at http://www.mysonicwall.com. I do know many versions of SonicOS has issues with VOIP. Mostly due to UDP translation on it NAT mapping. Enable consistent NAT "suppose" to address this issue. But it can be a hit and miss with different version of SonicOS. Another issue you may come across if you can get it to work is call drop off after "X" mins cause by its DOS protection. So, test it out thoroughly if you can get it to work. Bottom line is, Sonicwall is just not very friendly with VOIP. It requires a lot of tweaking to get it to work right. If you are not using any other features like its VPN or Gateway AV protection from your TZ150, you may want to consider replacing it with a more simple firewall like the Netgear VPN firewall or the Cisco small business router.

 

[mylove4life]

There is no need to replace anything... Its just a config issue. Why go to a cheap firefall..

Try updating the SonicOS to a newer version. You can download a newer version at http://www.mysonicwall.com. I do know many versions of SonicOS has issues with VOIP. Mostly due to UDP translation on it NAT mapping. Enable consistent NAT "suppose" to address this issue. But it can be a hit and miss with different version of SonicOS. Another issue you may come across if you can get it to work is call drop off after "X" mins cause by its DOS protection. So, test it out thoroughly if you can get it to work. Bottom line is, Sonicwall is just not very friendly with VOIP. It requires a lot of tweaking to get it to work right. If you are not using any other features like its VPN or Gateway AV protection from your TZ150, you may want to consider replacing it with a more simple firewall like the Netgear VPN firewall or the Cisco small business router.

 

[albertc]

There is no need to replace anything... Its just a config issue. Why go to a cheap firefall..

The TZ150 is quite old and not very flexible in terms of configuration. And the performance is not as good compare to those new "cheap" firewall. Most importantly, even the latest TZ firewalls like the TZ100,200,210...etc with the latest SonicOS have problems with voip. Dont get me wrong, i like sonicwall and it is one of my prefer brand of recommendation for my clients and I use them in my office (TZ210) and home (TZ100). But to get it to work with 3CX require some extra efforts and a few calls to the tech support department just to get it right.

 

[mylove4life]

thery are a very good basic firewall, much better than new cheap junk out ...

 

[semtex65]

HI All,

Thanks for the responses. To clarify points/questions raised:

Any phone behind the TZ150 has this same connection issue - thats Cisco 7940's and Snom 300's I've tried. 3CX soft phone does work, with tunneling enabled. Obviously, the hard phones don't have this feature. I have seen the Tunnel proxy thing that you run on a PC to get around this, but as there's no server on site there it would have to run on an end users machine; it all gets a bit messy - would rather go through the motions and get it done properly.

Those same phones have been working fine behind several other routers (Netgear, Thomson, Cisco to name a few)

Getting rid of the SonicWall? Not an option.. the TZ150 is part of a VPN setup with our head office and has been running great for years, so it will be staying.

I'll see if I can get hold of new firmware for the '150 and let you know how I get on.

 

[semtex65]

Well, I would upgrade the firmware... But according to MySonicwall, the TZ150 has already been registered with another account - and no one in our company knows who did. So I can't get hold of the firmware!

 

[albertc]

Any phone behind the TZ150 has this same connection issue - thats Cisco 7940's and Snom 300's I've tried. 3CX soft phone does work, with tunneling enabled. Obviously, the hard phones don't have this feature. I have seen the Tunnel proxy thing that you run on a PC to get around this, but as there's no server on site there it would have to run on an end users machine; it all gets a bit messy - would rather go through the motions and get it done properly.

Again, I have nothing against Sonicwall. I use it for my business from all the way back to their Soho series 10+years ago and it does the jobs well. But because I use it myself and support them myself for many years, I know their pros and cons. VOIP is just not their strong area. If you really need to keep the TZ150, see if you can get a more update SonicOS. The oldest SonicOS I can get is for a TZ170 @ version 3.1.6.3s, although it should work with the TZ150, I dont want to take the risk of breaking your firewall. Knowing the SonicWalll offers, you may want to consider upgrade it to their TZ100 http://www.sonicwall.com/us/products/TZ_100.html . It will work with your VPN link to your head office and I know for sure it will work with all of your sip phones that are configured as remote extension.