08. Nov 2026
1 min
IPTables is a powerful firewall tool on Linux. The basic options are: -A to add a rule, -D to delete a rule and -L to list all rules.
Targets can be ACCEPT, DROP, REJECT and so on. For example, iptables -A FORWARD -i [INTERFACE] -j DROP drops all forwarded (routed) packets arriving on a specific interface. Packets addressed to the server itself pass through the INPUT chain instead.