topic Re: 3CX Phone System behind Check Point 3100 in Firewall and Security Management

3CX Phone System behind Check Point 3100

Mboux23 — Thu, 11 May 2023 05:26:39 GMT

Hello

Has anybody ever made 3CXPhone System Check Point Security Gateway | R80.40.

Tried options found here and ever the internet but 3CX firewall checker fails every time.

I have added all necessary NAT rules and NAT port translation

Re: 3CX Phone System behind Check Point 3100

PhoneBoy — Thu, 11 May 2023 19:09:12 GMT

I suspect you will need to do a static NAT to a different IP address (not the firewall's external IP).
This is based on this thread for one of our SMB appliances: https://community.checkpoint.com/t5/SMB-Gateways-Spark/3CX-Phone-System-behind-1450-Appliance/m-p/108124#M4679

Re: 3CX Phone System behind Check Point 3100

Mboux23 — Fri, 12 May 2023 07:05:55 GMT

Hi PhoneBoy

Thanks for your reply.

Your suggestion have resolve my isuue. I did Static NAT and its work fine now and firewall check passed sucessfully.

Re: 3CX Phone System behind Check Point 3100

Naguinix — Mon, 03 Mar 2025 15:35:21 GMT

How did you disable the sip alg?

I'm trying the same thing and my test stays on sip alg.

Re: 3CX Phone System behind Check Point 3100

Mboux23 — Tue, 04 Mar 2025 05:13:51 GMT

Hi James

Have you already configured Static NAT on your firewall? Also, are all the necessary ports open?

WAN IP in static NAT. Hide outgoing traffic and Force translate. You just need to create a Static NAT rule on your firewall, mapping your 3CX server IP to your WAN IP.