Switchvox phone issues



  • Hello all, maybe someone here can help us out.
    We have a client who connects to our Switchvox system by registering their phones over the internet to our phone server.
    Sometimes, it seems kinda random, you can't make calls from one desk to another, the call will ring twice and then go to voicemail, other times it works fine.
    Sometimes the same thing happens when you transfer a call. The person you are transferring to never has their phone ring, and the call goes to VM.
    Sometimes when leaving a voicemail, it never actually records the message.
    Again, all of this is sometimes ...
    It does seem however, that when you call someone and it fails, if you immediately call them again, it works several times in a row.
    This client used to be our WAN and the phones registered that way, and never had an issue.
    Now, they outsourced their IT, and got another internet connection that they are using through a SonicWall appliance, so all the phones were switched to register to the public IP of our phone server over their new internet connection.
    Outgoing calls from the system always seems to work fine.
    The issue seemed to be that the packets being sent to the phones just again sometimes don't get there. The vendor's IT worked with Sonicwall and changed some NAT rules and some UDP settings, and that seemed to alleviate for a day, but now the issue is back.
    Our phone server sits behind a Cisco ASA with a public IP NAT.
    Anyone have any ideas?



  • First guess... only one of two ports needed are being passed.




  • Service Provider

    Any chance that SIP-ALG is still on on that SonicWall? SonicWalls are infamous for breaking SIP communications.



  • @scottalanmiller

    Hey SAM, I sent the vendor a link to the Digium SonicWall reference, http://support.digium.com/articles/FAQ/What-Are-Relevant-Sonicwall-Settings-for-Switchvox?popup=false
    I will ask about the SIP-ALG.
    thanks as always.


  • Service Provider

    @whoolly said in Switchvox phone issues:

    @scottalanmiller

    Hey SAM, I sent the vendor a link to the Digium SonicWall reference, http://support.digium.com/articles/FAQ/What-Are-Relevant-Sonicwall-Settings-for-Switchvox?popup=false
    I will ask about the SIP-ALG.
    thanks as always.

    Often it is cheaper to replace a SonicWall with higher end enterprise gear than it is to work on the existing box. That's not a stretch, that's real world. A higher end system is about $95 from Ubiquiti that doesn't have the same VoIP problems. So if the hourly billing to work on the SonicWall approaches $95 (plus the time to install the replacement) it can end up being worlds cheaper to just replace it than to fix it.


  • Service Provider

    Typically people buy SonicWall and such for the UTM functionality. these functions will also break things.


  • Service Provider

    @scottalanmiller said in Switchvox phone issues:

    @whoolly said in Switchvox phone issues:

    @scottalanmiller

    Hey SAM, I sent the vendor a link to the Digium SonicWall reference, http://support.digium.com/articles/FAQ/What-Are-Relevant-Sonicwall-Settings-for-Switchvox?popup=false
    I will ask about the SIP-ALG.
    thanks as always.

    Often it is cheaper to replace a SonicWall with higher end enterprise gear than it is to work on the existing box. That's not a stretch, that's real world. A higher end system is about $95 from Ubiquiti that doesn't have the same VoIP problems. So if the hourly billing to work on the SonicWall approaches $95 (plus the time to install the replacement) it can end up being worlds cheaper to just replace it than to fix it.

    Not his problem.

    Said company hired a third party ITSP to mangle it. It is their problem.


  • Service Provider

    @jaredbusch said in Switchvox phone issues:

    @scottalanmiller said in Switchvox phone issues:

    @whoolly said in Switchvox phone issues:

    @scottalanmiller

    Hey SAM, I sent the vendor a link to the Digium SonicWall reference, http://support.digium.com/articles/FAQ/What-Are-Relevant-Sonicwall-Settings-for-Switchvox?popup=false
    I will ask about the SIP-ALG.
    thanks as always.

    Often it is cheaper to replace a SonicWall with higher end enterprise gear than it is to work on the existing box. That's not a stretch, that's real world. A higher end system is about $95 from Ubiquiti that doesn't have the same VoIP problems. So if the hourly billing to work on the SonicWall approaches $95 (plus the time to install the replacement) it can end up being worlds cheaper to just replace it than to fix it.

    Not his problem.

    Said company hired a third party ITSP to mangle it. It is their problem.

    Often cheaper to replace the ITSP in that case, too ;)



  • Thanks everyone, after getting the vendor all of Digium's sonic wall reference, they made all the changes and things so far appear to be back to normal.


  • Service Provider

    @whoolly said in Switchvox phone issues:

    Thanks everyone, after getting the vendor all of Digium's sonic wall reference, they made all the changes and things so far appear to be back to normal.

    Good to hear.



  • Apparently spoke too soon.
    The vendor providing the Sonicwall and the client are now saying same issues again.
    You will call from one extension to another and it will ring twice and go to VM.
    Sometimes this happens a couple of times before the call will go through.
    firewall provider says that they have made all of the switchvox recommended settings.
    So any other ideas?
    I will try to coordinate a call between Switchvox support and the Sonicwall provider.


  • Service Provider

    Could be UDP threshold settings.



  • They told me that they changed it to 3600 instead of 30s.
    They also said that Sonicwall told them that they had to have a NAT statement to translate my phone servers public IP into something on their network, so they are translating it to the IP of on of their switches.
    That doesn't make any sense to me at all.
    I have a little meraki firewall that we use for a spare cable modem connection, i put 2 phones onto that and registered the phones and have not had any issues.


  • Service Provider

    @whoolly said in Switchvox phone issues:

    They told me that they changed it to 3600 instead of 30s.
    They also said that Sonicwall told them that they had to have a NAT statement to translate my phone servers public IP into something on their network, so they are translating it to the IP of on of their switches.
    That doesn't make any sense to me at all.
    I have a little meraki firewall that we use for a spare cable modem connection, i put 2 phones onto that and registered the phones and have not had any issues.

    Yup, if you are paying anything for the support and this is not already all included, I highly recommend the tiny cost of buying a Ubiquiti and replacing the SonicWall. This won't just fix this one little issue, but remove technical debt and deal with issues like this long into the future.



  • Client will not replace the Sonicwall and insists that they do this all the time and never have any voip issues with Sonicwall. They now want to do a L2L VPN tunnel for the voice network back to the internal IP of our PBX. I would rather not do this, but the boss wants the issue resolved.
    As I said before, they are trying to do a NAT of my public IP of my PBX to the internal IP of one of their layer 2 switches .. why ... I dunno.
    I am no network guru in any stretch, but this doesn't seem right at all.
    see below quote from client and sonic wall

    "Spoke with another Sonicwall support engineer regarding Sonicwall ticket #42488945, the VoIP phone system issue. The Sonicwall engineer noted that when traffic is initiated by the external PBX (SwitchVOX at SC Boro) the destination port is a random port number anywhere in the 10,000’s range. The Sonicwall, as it is currently configured, properly allows and forwards this traffic to the Internal SCboro Gateway which is one of the Cisco SF300 switches at 10.1.8.6. This switch does not know where to forward the traffic for this destination port. The Sonicwall engineer stated that there would have to be an internal voice server that could interpret the destination ports and forward the voice traffic to the appropriate VoIP phone, or the external SwitchVOX would have to bind the destination ports with the VoIP phone extensions."

    Do you have any suggestions on where to go next?



  • Have you checked the "port translation" on the Sonicwall?



  • I don't have any access to the Sonicwall, and am not familiar with their setup.
    I can ask the vendor, what specifically should they be looking at?



  • Sounds like you need to Fire your vendor.



  • @whoolly said in Switchvox phone issues:

    I don't have any access to the Sonicwall, and am not familiar with their setup.
    I can ask the vendor, what specifically should they be looking at?

    Sonicwall has a feature (that is on by default) called "port translation".
    Data comes in on port x, data exits on port x+1.
    This causes problems for SIP traffic.


  • Service Provider

    @whoolly said in Switchvox phone issues:

    Client will not replace the Sonicwall and insists that they do this all the time and never have any voip issues with Sonicwall. They now want to do a L2L VPN tunnel for the voice network back to the internal IP of our PBX. I would rather not do this, but the boss wants the issue resolved.

    Oh, this is a client not internal? Keep the SonicWall, that's a consultants' dream gear. Breaks constantly needs loads of hours to support. If they want a VPN, they are pretty clear that they know the SonicWall doesn't work.


  • Service Provider

    @dashrender said in Switchvox phone issues:

    Sounds like you need to Fire your vendor.

    Client likes the situation, though. So not his problem.



  • Oh well If they are your client and they refuse to replace I guess that is a bonus for you.... more billing.


  • Service Provider

    @dashrender said in Switchvox phone issues:

    Oh well If they are your client and they refuse to replace I guess that is a bonus for you.... more billing.

    Exactly. Clear conscience that the proper resolution was recommended. Now he can happily bill without feeling badly. Win / win.



  • @whoolly said in Switchvox phone issues:

    Now, they outsourced their IT, and got another internet connection that they are using through a SonicWall appliance, so all the phones were switched to register to the public IP of our phone server over their new internet connection.

    OK, so there's a third party IT group involved here. Did you tell them, the third party IT group about the known issues with SonicWalls and VOIP, or did you tell the actual client of yours?

    Since they used to be a direct client, that then changed IT departments, it's hard to say who you even have a right to talk to at the ultimate end user.

    Assuming you still have the right to talk to the ultimate end user - I would call those folks directly, inform them of the issue (i.e. the new IT company is refusing to replace the end user's firewall for something that is know to work, and instead the end user is getting bilked not only for the IT companies extra billing, but also the potential extra costs coming from you, the phone provider).

    If the end user then says - do what the IT company wants, then you're hands are truly clean, BILL BILL BILL!



  • we ended up going the route of the L2L VPN to get the phones to work. Vendor insisted he has never had any VOIP issues with Sonicwall and didn't want to budge on that. After a day of them figuring out how to put the phones on a separate Vlan and then getting that traffic to the firewall, we finally got the vpn up and working and the phones registered again. All in all a very frustrating experience, thanks to everyone here for the help.
    If only we could charge by the hour, but we don't as we are one gov agency helping another.
    If anyone else here besides SAM will be in Austin later this year, see you at Touche's.


  • Service Provider

    @whoolly said in Switchvox phone issues:

    we ended up going the route of the L2L VPN to get the phones to work. Vendor insisted he has never had any VOIP issues with Sonicwall and didn't want to budge on that. After a day of them figuring out how to put the phones on a separate Vlan and then getting that traffic to the firewall, we finally got the vpn up and working and the phones registered again. All in all a very frustrating experience, thanks to everyone here for the help.
    If only we could charge by the hour, but we don't as we are one gov agency helping another.
    If anyone else here besides SAM will be in Austin later this year, see you at Touche's.

    Sorry not to be more help.


  • Service Provider

    @whoolly said in Switchvox phone issues:

    Vendor insisted he has never had any VOIP issues with Sonicwall and didn't want to budge on that.

    Even while it doesn't work. So you know that he'll say this to other customers now, even after this one. Chances are, he's had problems at all customers. SonicWall is culprit #1 for VoIP issues. I mean that literally. I get a call that someone has VoIP audio issues, my first question is always "Do you have a SonicWall?" Nine times out of ten, the answer is yes and nine times out of those ten, the SW was the issue. It's nearly a sure bet with audio issues.

    Had you led this question purely with "I have these audio issues..." we'd have said "I bet you have a SonicWall."



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