Prevent brute-force attack by rate-limiting connections (iptables)

A quick and easy way to prevent or dramatically-hinder brute-force attacks to limit the rate of new connections.

Allow a maximum of 3 SSH connections per minute:

-A INPUT -p tcp --dport 22 -m state --state NEW -m limit --limit 3/min --limit-burst 3 -j ACCEPT

Ensure this rule is above the INPUT rule that allows the connections, or replaces it.

Category:Linux Category:Iptables