[GTALUG] Ubuntu -- Disabling Ping

[Howard Gibson]

   I am playing with my hack Ubuntu machine, and I am sorting out
security. I want to disable ping.  This is a laptop, and I want to
document the application of aluminium foil.

   The standard ping disabler is the following line...

# echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all

   This works fine on my Fedora laptop.  On Ubuntu, I get...

$ sudo echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all
-bash: /proc/sys/net/ipv4/icmp_echo_ignore_all: Permission denied

   The file exists.  I can print it with "cat" (it prints "0".  Why can
I not change it?  

-- 
Howard Gibson 
hgibson at eol.ca
jhowardgibson at gmail.com
http://home.eol.ca/~hgibson