3CX RTP Firewall 'Other' Ports

P4ul

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Afternoon All,

I have a 3CX (V20) install on a different subnet (10.251.11.2) to the IP phones (10.241.11.0/24). I have opened ports 9000-10999 and 5060-5063 between the IP Phones and the PBX and two way audio is working fine.

When I attempt to use the *777 echo test, I have noticed that the PBX seems to be opening ports in the 70XX range for RTP, so audio is not being delivered.

Does anyone happen to know the full range of ports that could be in use here, and are there any other ranges like this that could catch me out?

In the picture examples attached, the phone opens port 10008 for RTP, but the PBX opens 7078.

Thanks in advance for any advice!
 

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Ports 7000-8999 are for lan connections over rtp.
 
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Ports 7000-8999 are for lan connections over rtp.
Thanks, now I have the full range I can see a lot more information about this. Couldn't find the range listed anywhere on the official firewall docs, but I guess most people are using SBC for phones in a different subnet.
 
Thanks, now I have the full range I can see a lot more information about this. Couldn't find the range listed anywhere on the official firewall docs, but I guess most people are using SBC for phones in a different subnet.
Yes, its not documented very well... I dont know why.
 

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