===== IPTables =====

==== Configure ====

=== List rules ===

<code>
iptables -L
#or
iptables -L -n
</code>

=== Add rule ===

<code>
#reject connections
iptables -A <CHAIN> -d <IP>/32 -j REJECT --reject-with icmp-port-unreachable
</code>

=== Remove rule ===

<code>
#list rules in chain
iptables -L <CHAIN> --line-numbers

#remove line 1 in chain
iptables -D <CHAIN> 1
</code>


==== Backup and Restore ====

Create a backup
<code>
iptables-save > /backup/iptables-lunetikk-20190604.bck
</code>

Restore from a backup
<code>
iptables-restore < /backup/iptables-lunetikk-20190604.bck
</code>

This method can also be used to edit rules via vi.

===== Commands =====

^  Command  ^  Function  ^
|  %%iptables -L%%  |  List all rules  |
|  %%iptables -L --line-numbers%%  |  List all rules with numbers  |
|  %%iptables -L -w%%  |  Use -w if iptables is already in use, your command will retry until the proc is unlocked  |