Hi all, by default ISPConfig3 sets the default iptables rules which, in my case, are: iptables -L: Chain INPUT (policy ACCEPT) target prot opt source destination fail2ban-dovecot-pop3imap tcp -- anywhere anywhere multiport dports pop3,pop3s,imap2,imaps fail2ban-pureftpd tcp -- anywhere anywhere multiport dports ftp fail2ban-sasl tcp -- anywhere anywhere multiport dports smtp fail2ban-ssh tcp -- anywhere anywhere multiport dports ssh Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination Chain fail2ban-dovecot-pop3imap (1 references) target prot opt source destination RETURN all -- anywhere anywhere Chain fail2ban-pureftpd (1 references) target prot opt source destination RETURN all -- anywhere anywhere Chain fail2ban-sasl (1 references) target prot opt source destination RETURN all -- anywhere anywhere Chain fail2ban-ssh (1 references) target prot opt source destination RETURN all -- anywhere anywhere which seems to accept all the connections (if I am not wrong). I would like to apply a more restrictive iptables rules, for example something like the following: *filter # allow loopback traffic -A INPUT -i lo -j ACCEPT -A INPUT ! -i lo -d 127.0.0.0/8 -j REJECT # allow established connections -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT # allow outbound traffic -A OUTPUT -j ACCEPT # allow running services -A INPUT -p tcp --dport 80 -j ACCEPT -A INPUT -p tcp --dport 443 -j ACCEPT -A INPUT -p tcp --dport 8080 -j ACCEPT -A INPUT -p tcp --dport 143 -j ACCEPT -A INPUT -p tcp --dport 993 -j ACCEPT -A INPUT -p tcp --dport 587 -j ACCEPT -A INPUT -p tcp --dport 110 -j ACCEPT # allow SSH on port 22 -A INPUT -p tcp -m state --state NEW --dport 22 -j ACCEPT # log denied iptables calls -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7 # denie all the remaining inbound traffic -A INPUT -j REJECT -A FORWARD -j REJECT COMMIT Can I completely change the rule file? how can I merge the two without lost the fail2ban rules? Thank you very much.
