This will also look similar to the iptables rules configuration files, if you’ve ever used iptables-persistent or iptables save. A TCP -p tcp -m tcp -dport 22 -j ACCEPTĪs you can see, the output looks just like the commands that were used to create them, without the preceding iptables command. A INPUT -j REJECT -reject-with icmp-proto-unreachable A INPUT -p tcp -j REJECT -reject-with tcp-reset A INPUT -p udp -j REJECT -reject-with icmp-port-unreachable

A INPUT -p icmp -m conntrack -ctstate NEW -j ICMP A INPUT -p tcp -m tcp -tcp-flags FIN,SYN,RST,ACK SYN -m conntrack -ctstate NEW -j TCP A INPUT -p udp -m conntrack -ctstate NEW -j UDP A INPUT -m conntrack -ctstate INVALID -j DROP A INPUT -m conntrack -ctstate RELATED,ESTABLISHED -j ACCEPT To list out all of the active iptables rules by specification, run the iptables command with the -S option: $sudo iptables -S Example: Rule Specification Listing

Flush all chains and tables, delete all chains, and accept all traffic.

Flush chains (delete all rules in a chain).

In this tutorial, we will cover how to do the following iptables tasks: While many iptables tutorials will teach you how to create firewall rules to secure your server, this one will focus on a different aspect of firewall management: listing and deleting rules. Iptables is a firewall that plays an essential role in network security for most Linux systems.

Show iptables