Re: block pings
On Wed, 30 Aug 2000, Danny Pansters wrote:
> On Tue, 29 Aug 2000, Nick wrote:
> > how do you stop linux from replying to pings like
> >
> > microsoft does. you can't ping www.microsoft.com or www.msn.com
> >
> > thankx nick
>
> OK, I got curious since it involves icmp, so it's not done in
> /etc/inetd.conf, and I didn't know how to do it.
> All I can say is RTFM, it's right there in the icpm man page that
> I tried first.
>
> Just put this in /etc/sysctl.conf to turn ping replies off:
>
> net/ipv4/icmp_echo_ignore_all=1
>
> Then run
>
> # sysctl -p
>
> But after that you should really go back to /etc/sysctl.conf and get rid of
> it again (hint: it involves running sysctrl again :-).
Another fine hack would be this:
ipchains -A input -i ppp0 -p icmp --icmp-type 8 -j DENY
ipchains -A output -i ppp0 -p icmp --icmp-type 0 -j REJECT
ICMP type 8 is echo-request. type 0 is echo-reply.
Replace ppp0 by whatever you use to connect to the internet.
Just my $0.02
Sebastian
email: sebastian.ritter@web.de
Reply to: