Looking for why pfSense port forwarding is not working? Here’s the reason and a quick fix.

A few days ago, we came across this error message. And we fixed it by checking the pfSense setting and other system settings that can block pfSense.

At Bobcares, we often get requests to fix pfSense error, as a part of our Server Management Services.

Today, we will see how our Support Engineers fix this port forwarding error.

Why pfSense port forwarding does not work?

pfSense is an open-source firewall and router. Usually, we install it on a physical machine to make a dedicated firewall for a network.

Basically, it is quite easy to forward ports in pfSense.

But what if it does not work?

There are so many reasons why this does not work. Let’s have a look at a few of them.

1. In many cases, improper adding of the firewall or NAT rules causes trouble in port forwarding.
2. Another possible reason is firewall rules in the client machine.
3. Similarly, if pfSense is not the default gateway of the client machine. Also if the client machine is not listening on the forwarded port.
4. Otherwise, some upstream services can block pfSense forwarded port.
5. Testing port forwarding from the internal network itself.

So far, we have seen the most probable reasons that can cause port forwarding, not to work.

How we make the pfSense port forwarding work?

Customers often approach us when pfSense port forward does not work. In such a situation our Support Engineers troubleshoot and fix the error. Let’s have a look at each of them.

1. Check the steps in pfSense port forwarding

We check if the port forwarding is done correctly or not. If our Support Engineers find any error, we try to delete those rules.

Sometimes, we do the port forwarding from the beginning. Thus we ensure that the port forwarding works.

2. Test pfSense port forwarding outside the network

Most importantly, port forwarding does not work internally. For this first, we need to enable NAT reflection.

So our Support Engineers test the port from outside network.

3. Edit firewall rules

Similarly, we check the firewall rules in the system. Our Support Engineers edit these rules in such a way that passes traffic for NAT entry. Also, this enables logging.

Later we check the firewall status from Status >> System Log >> Firewall. This gives the details of NAT traffic.

4. Check state table

Another option is to check the state table. For this, we navigate as Diagnostics >> States. We check the entries in this table. And resolve the error related to the improper entries.

And example state table appears as,

5. Use a Packet Capture or tcpdump

We also recommend using a Packet Capture or tcpdump. Our Support Engineers with expertise in networking troubleshoot the error.

For this, we select the Diagnostics. Here we select Packet Capture to capture traffic or use tcpdump for the shell. After applying appropriate filters, we check for the reason for the error. Later, we resolve it.

[Need assistance in pfSense port forwarding? – We will help you.]

Conclusion

In short, pfSense port forwarding doesn’t work due to many reasons. Mostly, this is due to improper setup or firewall rules in the system. Today, we saw how our Support Engineers troubleshoot and fix this error.