Issue with outgoing voice traffic

[jonathanjohnsn]

I am having an issue with outgoing voice traffic. I can hear the opposite party with no problem, but the other party cannot hear me. I am pretty certain I have my router configured correctly, or it wouldn't work at all. While this next part is probably quite hard to believe, but when I run wireshark, the other party can hear me fine. I have tested this strange finding many times, and every time I close out Wireshark and make a call the conversation skipping starts again. I am well aware that wireshark does not do anything with traffic other than log it. I have tried to edit the local policy settings on the server and create a qos 56 policy for 3CXPhoneSystem.exe, and I haven't gotten anything different.

I will mention as well, in the wireshark logs the incoming packets from my sip provider are fully assembled, where the ones coming from my 3cx box have an error with the packet heading. Also, this isn't just packets going from the 3cx host to the sip provider, but packets going from the 3cx server to the ip phones as well.
Does anyone have any ideas?

Thanks in advance!
Jonathan

 

[eagle2]

This is definitely a NAT / firewall issue.

Can you provide more details about your setup, scheme, firewall configuration, addresses used, setting of phones, wireshark logs, etc. If any of these details sensitive, please hide them.

Regards

 

[jonathanjohnsn]

I have a 3Mbit bonded loop for my internet connection, in which I host my sip trunks. I use a sonicwall TZ100 for my router. My 3CX box is a dell poweredge with 8 cores and 8 gb of ram, it is on the LAN side of course.

Incoming (WAN>LAN) I can hear them with no issues (works good)
Outgoing (LAN>WAN) It is sporadic pauses and skips

Here are screenshots for my LAN>WAN firewall policies and my NAT Policies:

Let me know if you need anything else. Thanks for looking at my issue.

Jonathan

 

[SY]

I will mention as well, in the wireshark logs the incoming packets from my sip provider are fully assembled, where the ones coming from my 3cx box have an error with the packet heading. Also, this isn't just packets going from the 3cx host to the sip provider, but packets going from the 3cx server to the ip phones as well.
Does anyone have any ideas?

Hi Jonathan,
If you are asking about "checksum" issue like this then you should not care about it. Simply wireshark analizes packet before real check sum will be set in the header.

 

[willow]

make sure you hav consitent nat enabled and the sip alg disabled on the voip take if your router has them. you may also want to see if you can upgrade then firmware on that sonicwall. I have seen a lot weird things with the sonicwalls and sometimes upgrading them will help.

 

[jonathanjohnsn]

You can say that again. I thought that it was a good idea to have consistant NAT enabled, but the 3CX how to guide said not to, but Sonicwall support said to do it. When you said disable SIP alg, you are talking about 2nd checkbox under the VoIP category?

I have the firmware upgraded to the latest version.

Is everyone pretty sure it is a firewall issue, and not an issue with the server I am hosting 3cx on. I am hosting 3cx on the same server as my domain controller, file server, and print server. The server is a 8 core dell poweredge with 8gb ram, that is never taxed over 20% usage. But I am out of options, so I was going to put the 3CX on its own box. Any ideas?

Thanks again for your help,
Jonathan

 

[mylove4life]

One sure way to tell is to bypass the firewall, I did that with my Sonic to make sure it was not that... might help...

 

[willow]

yep the SIP alg is under the second check box.

 

[SY]

Sorry for the question but there is no answer to it in the initial post.
Who is the provider of connection between your phone and remote party?
Is it VoIP provider?
Is it a direct connection to a remote extension?

Thanks

 

[jonathanjohnsn]

Stepan:
Thanks for your response. This is my current setup:

(SIP Trunk Provider)-----(Internet - Verizon-3Mbit Bonded Loop(2xT1))-----------(Sonicwall TZ100)----(LAN------[3CX Server])

Is there a router out there that I can configure, that 3CX highly recommends? It would be worth it to spend more money, than to keep fighting this issue...

 

[jonathanjohnsn]

While it clearly has to be a firewall issue..why does running wireshark make it work? I realize this makes no sense, but anyone who wants to verify that this is the case, I will be glad to prove it. I close wireshark make a test call it it starts skipping again. I open it back up, start the logging, and it works flawlessly again. I can actually be in the middle of a conversation, and close wireshark, and I can instantly hear the skipping. I am not saying it makes sense, but there has to be an explanation.

 

[eagle2]

I have a 3Mbit bonded loop for my internet connection, in which I host my sip trunks. I use a sonicwall TZ100 for my router. My 3CX box is a dell poweredge with 8 cores and 8 gb of ram, it is on the LAN side of course.

Incoming (WAN>LAN) I can hear them with no issues (works good)
Outgoing (LAN>WAN) It is sporadic pauses and skips

Let me know if you need anything else. Thanks for looking at my issue.

Jonathan

This is an indication for bandwidth problems with upload - may be your internet connection is too asymmetric and need to implement QoS in router.

Regards