Iptables nat rules list

Looking for how to list nat rules in iptables?

NAT is an inbuilt table in iptables for address translation.

Since NAT is not the default table, always mention the table-name with iptables queries relating to it.

At Bobcares, we get many queries regarding iptables rules, as a part of our Server Management Services.

Today, let’s see how our Support Engineers resolves these customer queries.

Iptables is the inbuilt firewall for Linux systems. NAT is the built-in table in iptables. Usually, we use the nat table for address translation.

The chains in the nat table are PREROUTING, INPUT, OUTPUT, and POSTROUTING.

Iptables use nat rules for address translation tasks like forwarding.

The filter table is the default table. So, rules executed without specifying the table-name will not show the nat rules.

Many of our customers have this query. But listing nat rules is a simple task. The iptables command with a few options will do this.

The default to list iptables rule is -L. And the command is,

iptables -L

This command just gives information about the default filter table. But iptables also have other options to show more specific results. For instance,

Hence to display nat rules our Support Engineers use the command,

We also use the command:

So, this lists all the rules regarding the nat table.

Usually, customers approach us with complaints about listing nat rules. The most common mistakes that users make are:

Many customers approach us with the query ‘iptables does not list rules i have created’. Firstly, we checked the command he used to list the rules.

But he created nat rules. So the mistake was due to an unspecified table-name. Our Support Team corrected his command to,

And this fixed his error.

Another major mistake is restarting the server without saving iptables. Usually, iptables stores its rules in memory. When users restart the server iptables reset as configured.

Hence after adding any rules to iptables, we always save it.

This command saves the rules to the iptables config file. And retrieves while restarting the server.

[Need assistance in creating iptables rules? – We’ll set it up for you.]

In short, we can see the iptables nat rules list when we specify the rule with table-name. Customers often get errors due to this. Today, we discussed how to list nat rules and also saw how our Support Engineers fix the related errors.