Linux network behavior wierdness

[Neil Joseph Schelly]

On Friday 05 September 2008 14:26, Paul Lussier wrote:
> Paul Lussier <p.lussier at comcast.net> writes:
> >> Watch out for /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts.  The
> >> default was changed between 2.6.13 and 2.6.14 to ignore by default.
> >
> > Ooh, I didn't know that, thanks!
>
> Fascinating, so how does this work?
>
>  $ ssh farm-519 ping -b 10.95.255.255 -c 1
>  64 bytes from 10.95.34.112: icmp_seq=1 ttl=64 time=0.074 ms
>  1 packets transmitted, 1 received, 0% packet loss, time 0ms
>
>  $ ssh farm-519 cat /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts
>  1

ping -b "farm-519's broadcast"
...ought to have no response from farm-519.  It won't respond to them, but it 
can still send broadcast pings.
-N