How to Configure Port Forwarding on pfSense Firewall
pfSense is a budget router with enterprise capability and is very customizable. However, it can be a bit tricky for a newbie. Hence, I’m publishing this to help out fellow ICT professionals who wish to try to out.
In this post, I’m going to go through the basic port forwarding configuration for incoming emails. I will forward all incoming emails through SMTP port 25 to my specific email server.
Enter the dashboard
When you login to the pfSense dashboard, go to Firewall and select NAT
Now add a port forwarding rule. Click the green add button to the right.
Configuring Port Forwarding
The Interface should be set to WAN i.e. you want traffic coming from the internet into your network. The protocol should be set to TCP.
In Destination the default should be WAN address. If it isn’t then change it. The Destination port range needs to be set to SMTP. Click the drop down and select it.
In the Redirect target IP box, enter the IP address of your email server, and also select SMTP in the Redirect port.
The final step is putting in a proper description before saving.
Summary
Essentially, the only things that you need to change are the IP addresses and the specific ports. This configuration is only for a single WAN. If you have more, then configuration will be different.
Although considered as a firewall/router, pfSense has capabilities that make it one of the best open source projects to date.
pfSense also has other great features that I will be exploring in the coming posts.
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