#Flush existing rules
iptables -F
# Set up default DROP rule for eth0 (Assuming eth0 is the Ethernet Port)
iptables -P INPUT DROP
# Allow existing connections to continue
iptables -A INPUT -i eth0 -m state –state ESTABLISHED,RELATED -j ACCEPT
# Accept everything from the 192.168.0.x network
iptables -A INPUT -i eth0 -s 192.168.0.0/24 -j ACCEPT
# Allow connections from this host to 192.168.1.10
iptables -A OUTPUT -o eth0 -d 192.168.1.10 -j ACCEPT