Part V. iptables firewall

Table of Contents

13. introduction to routers
router or firewall
packet forwarding
packet filtering
stateful
nat (network address translation)
pat (port address translation)
snat (source nat)
masquerading
dnat (destination nat)
port forwarding
/proc/sys/net/ipv4/ip_forward
/etc/sysctl.conf
sysctl
practice: packet forwarding
solution: packet forwarding
14. iptables firewall
iptables tables
starting and stopping iptables
the filter table
about packet filtering
filter table
setting default rules
changing policy rules
Allowing ssh over eth0
Allowing access from a subnet
iptables save
scripting example
Allowing ICMP(ping)
practice: packet filtering
solution: packet filtering
network address translation
about NAT
SNAT (Source NAT)
SNAT example setup
IP masquerading
DNAT (Destination NAT)