This protection will log all Spoofed Packets, Source Routed Packets, and Redirect Packets to your log files.
[root@deep] /# for f in /proc/sys/net/ipv4/conf/*/log_martians; do
> echo 1 > $f
Add the above commands to the /etc/rc.d/rc.local
script file and you'll not have to type it again the next time
you reboot your system.
Edit the /etc/sysctl.conf
file and add the following line:
# Log Spoofed Packets, Source Routed Packets, Redirect Packets
net.ipv4.conf.all.log_martians = 1
You must restart your network for the change to take effect. The command to manually restart the network is the following:
[root@deep] /# /etc/rc.d/init.d/network restart
Setting network parameters [ OK ]
Bringing up interface lo [ OK ]
Bringing up interface eth0 [ OK ]
Bringing up interface eth1 [ OK ]