Comments on: Linux Iptables allow or block ICMP ping request

By: help

help — Wed, 01 Feb 2012 18:18:20 +0000

hi,
i want to do ip spoofing for my excersize but i can’t !!!
the question is :
use iptables to modify your IP address to 10.2.3.4 when sending out icmp requests.

By: Snehal

Snehal — Tue, 25 Oct 2011 13:38:04 +0000

Thanks very much and appricate your knowledge sharing. This was helped me to block icmp traffic for my application testing.

By: Sun

Sun — Wed, 06 Oct 2010 16:43:03 +0000

Actually worked right away didnt need to restart atall thanks

By: Michael

Michael — Sat, 07 Aug 2010 17:38:32 +0000

Thanks a lot it worked perfectly for me.

By: Vivek Gite

Vivek Gite — Fri, 21 May 2010 16:12:30 +0000

Yes, you need to restart firewall if you made changes to config file.

Reload script if you made changes to a shell script that loads all other rules.

By: Bill

Bill — Fri, 21 May 2010 15:46:40 +0000

This may be a dumb question, but I can’t find the answer anywhere else. After I make a rule change, do I have to reload iptables or stop/start to activate the change?

By: Jorge Filippo

Jorge Filippo — Thu, 29 Oct 2009 11:11:20 +0000

How can I accept ICMP with a specific packetsize? I want to be able to ping my server from my windows notebook, but with -l 666 (for example), for monitoring purposes. But IPTABLES doesn’t seem to have an option to accept or denay a specific ping size. Is that correct?. Thanks in advance.

By: myHPLinuxdummyServersux

myHPLinuxdummyServersux — Tue, 20 Oct 2009 21:08:53 +0000

hi.. im from a networking background… couldnt play around that much at home coz of ChISCO too $$$$… i heard linux also can work as a router with their IPtables stuff… may i know:
1. SERVER_IP=”202.54.10.20″ is whos address? me as a server or the client’s IP?
2. 0/0 ?
3. NEW,ESTABLISHED,RELATED (try to understand this on9, maybe yall have a clearer explanation)
4. -m?

By: hamed

hamed — Fri, 07 Aug 2009 04:51:32 +0000

thank u alot

By: ashwani

ashwani — Fri, 24 Apr 2009 20:27:33 +0000

Nice…how about i can ping anyone but none cant ping me?…i mad lil rule

iptables -A OUTPUT -p icmp –icmp-type echo-reply -s 192.168.1.50 -d 192.168.1.0/24 -j REJECT

this for an single subnet :-)

By: Vivek Gite

Vivek Gite — Mon, 08 Dec 2008 20:20:48 +0000

@ak,

You must replace $SERVER_IP with actual IP address or create a variable itself.

By: Bill

Bill — Mon, 08 Dec 2008 18:48:07 +0000

AK, you have a typo. Should be “–state”

By: ak

ak — Mon, 03 Nov 2008 03:13:21 +0000

iptables -A INPUT -p icmp –icmp-type 8 -s 0/0 -d $SERVER_IP -m state –state NEW,ESTABLISHED,RELATED -j ACCEPT

Error: Bad argument `state’

By: Hide IP

Hide IP — Sun, 02 Dec 2007 07:51:05 +0000

Thanks for info! We’ll use this info in our script firewall.

By: vivek

vivek — Mon, 08 Oct 2007 05:02:30 +0000

–state will improve security and it is one of the best features of Iptables. I recommend keeping it..

By: China Landscape

China Landscape — Mon, 08 Oct 2007 04:48:13 +0000

Hi,

Thanks for your tip, it’s work perfectly.
Just one question :
Is the options –state NEW,ESTABLISHED,RELATED are mandatory ?

China Landscape

By: OSCAR

OSCAR — Thu, 28 Jun 2007 16:58:48 +0000

Hi,
How block ping request with ENDIAN firewall?
Best regards

By: LinuxTitli

LinuxTitli — Tue, 31 Jan 2006 21:52:00 +0000

fsckyou, you are right i have updated the entire rules, thanks :D

By: LinuxTitli

LinuxTitli — Tue, 31 Jan 2006 21:51:00 +0000

I have updated post as per your request see above.

By: Anonymous

Anonymous — Tue, 31 Jan 2006 19:45:00 +0000

i need to disable ougoing ICMP from my server with iptables, how do I do that?