How to stop ping,

divyashree · 08-09-2009, 09:02 AM

I want to know how to stop ping my system from other system by using iptables

I used the following,still ping working.

Quote:

[root@server1 ~]# iptables -A INPUT -s 172.24.0.0/16 -d 172.24.0.254 -p tcp --dport 5813 -j REJECT
[root@server1 ~]# iptables -A INPUT -s 172.24.0.0/16 -d 172.24.0.254 -p udp --dport 5813 -j REJECT

GrapefruiTgirl · 08-09-2009, 09:23 AM

Ping uses a 'protocol' of its own, not tcp or udp. It's ICMP.

Check HERE for further info/help too

Sasha

divyashree · 08-09-2009, 09:31 AM

Quote:

Originally Posted by GrapefruiTgirl

Ping uses a 'protocol' of its own, not tcp or udp. It's ICMP.

Check HERE for further info/help too

Sasha

Bro,I think u didn't go through my question,I mentioned there what I had done,I used port 5813 for ICMP protocol there.

unSpawn · 08-09-2009, 09:37 AM

Quote:

Originally Posted by divyashree

Bro,I think u didn't go through my question,I mentioned there what I had done,I used port 5813 for ICMP protocol there.

Be careful who you "bro" ;-p

I don't know how to break it to you nicely but it seems you don't understand ICMP. Please see http://www.faqs.org/rfcs/rfc792.html. Note that blocking all ICMP types breaks networking RFC compliance, makes troubleshooting harder and if blocking ICMP is done for achieving "stealth" it's just misperception. Instead allow some Types and rate-limit them and log and block others.

repo · 08-09-2009, 09:40 AM

Code:

iptables -A INPUT -p icmp -m icmp --icmp-type echo-request -j DROP

or

Code:

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

divyashree · 08-09-2009, 10:16 AM

Quote:

Originally Posted by repo

Code:

iptables -A INPUT -p icmp -m icmp --icmp-type echo-request -j DROP

or

Code:

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

repo, thanks a lot.Ur iptable helped me,but I want to know wheather any mistake in my iptables as I did.I taught to do like this for blocking different types of services with their ports.

repo · 08-09-2009, 10:19 AM

As Sasha already told you,
Pings use the ICMP protocol and doesn't use ports like TCP or UDP.

divyashree · 08-09-2009, 10:43 AM

Quote:

Originally Posted by repo

As Sasha already told you,
Pings use the ICMP protocol and doesn't use ports like TCP or UDP.

Actually I know that,but in case of opertaion with ftp/ssh/pop/imap/squid protocols I use the same type of rules using tcp and udp with --dport <port-used-by-protocol> and all works fine .
I am newer to iptables and I do as I am guided .So not gone deep.
Anyway thanks a lot.