Faster way paste this on console
/sbin/iptables -F && /sbin/iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP && /sbin/iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP && /sbin/iptables -A INPUT -p tcp --tcp-flags ALL ALL -j DROP && /sbin/iptables -I INPUT -p icmp -m icmp --icmp-type echo-request -j ACCEPT && /sbin/iptables -A INPUT -i lo -j ACCEPT && /sbin/iptables -A OUTPUT -o lo -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 443 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 21 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 25 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 465 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 110 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 995 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 143 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 993 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT && /sbin/iptables -I INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT && /sbin/iptables -P OUTPUT ACCEPT && /sbin/iptables -P INPUT DROP
New script only open port 80, 443, 25, 465,587
/sbin/iptables -F && /sbin/iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP && /sbin/iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP && /sbin/iptables -A INPUT -p tcp --tcp-flags ALL ALL -j DROP && /sbin/iptables -I INPUT -p icmp -m icmp --icmp-type echo-request -j ACCEPT && /sbin/iptables -A INPUT -i lo -j ACCEPT && /sbin/iptables -A OUTPUT -o lo -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 443 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 25 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 465 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 587 -j ACCEPT && /sbin/iptables -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT && /sbin/iptables -I INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT && /sbin/iptables -P OUTPUT ACCEPT && /sbin/iptables -P INPUT DROP
IP-Tables are not persistent On Debian 8, save permanent the new rules to the master iptables file:
#/usr/sbin/iptables-save > /etc/iptables.up.rules
Make sure the iptables rules are started on a reboot we’ll create a new file:
#vim /etc/network/if-pre-up.d/iptables
Add these lines to it:
#!/bin/sh /sbin/iptables-restore < /etc/iptables.up.rules
The file needs to be executable so change the permissions:
#chmod +x /etc/network/if-pre-up.d/iptables
#/usr/sbin/iptables -L Chain INPUT (policy DROP) target prot opt source destination ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED ACCEPT icmp -- anywhere anywhere icmp echo-request DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/NONE DROP tcp -- anywhere anywhere tcp flags:!FIN,SYN,RST,ACK/SYN state NEW DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/FIN,SYN,RST,PSH,ACK,URG ACCEPT all -- anywhere anywhere ACCEPT tcp -- anywhere anywhere tcp dpt:http ACCEPT tcp -- anywhere anywhere tcp dpt:https ACCEPT tcp -- anywhere anywhere tcp dpt:ftp ACCEPT tcp -- anywhere anywhere tcp dpt:smtp ACCEPT tcp -- anywhere anywhere tcp dpt:urd ACCEPT tcp -- anywhere anywhere tcp dpt:pop3 ACCEPT tcp -- anywhere anywhere tcp dpt:pop3s ACCEPT tcp -- anywhere anywhere tcp dpt:imap2 ACCEPT tcp -- anywhere anywhere tcp dpt:imaps ACCEPT tcp -- anywhere anywhere tcp dpt:ssh
Debian 10 IPtables persistent make your iptables rules persistent install iptables-persistent package:
#apt-get install iptables-persistent
Debian 10 IPtables Save to update iptables with new rules use IPtables Save
# iptables-save > /etc/iptables/rules.v4 # ip6tables-save > /etc/iptables/rules.v6
Debian 10 Restore to restore iptables configuration form iptables
# iptables-restore < /etc/iptables/rules.v4