1 Blokir dengan IPTABLES

blokir url di iptables
iptables -A OUTPUT -p TCP -d www.google.com -j DROP
iptables -A OUTPUT -p ICMP -d www.google.com -j DROP

blokir ip computer
iptables -t filter -A INPUT -s 192.168.1.122 -j DROP

blokir
iptables -A INPUT -s 102.168.1.0/255.255.255.0 -p ICMP -j DROP

Blokir portscanning ( syn )
iptables -A INPUT -s ! 192.168.1.0/24 -p TCP -dport 80 -syn -j DROP

iprange
iptables -A INPUT -s 192.168.1.112/192.168.1.254 -p TCP -j ACCEPT

iptables -A INPUT -m iprange –src-range 192.168.1.122-192.168.1.254 -p TCP -j DROP

block port
iptables -A INPUT -p tcp –dport 1214:1216 -j DROP ( REJECT )

command2
iptables -F menghapus smua config

iptables -D output 2 -->menghapus config output line 2
iptables -D INPUT -s 192.168.1.122 -->menghapus specific file

konfigurasi == > vi /etc/sysconfig/iptables-config

rules vi /etc/sysconfig/iptables
\
iptables -A INPUT -s 192.168.1.122 -p UDP -j DROP

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