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Commands tagged iptables

Commands tagged iptables from sorted by
Terminal - Commands tagged iptables - 16 results
while true; do iptables -nvL > /tmp/now; diff -U0 /tmp/prev /tmp/now > /tmp/diff; clear; cat /tmp/diff; mv /tmp/now /tmp/prev; slee p 1; done
2012-04-15 00:02:33
User: unixmonkey34223
Functions: cat diff iptables mv
Tags: grep iptables watch diffe
0
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watch iptables counters

this alternative shows the differences as they occur so that they are made plain

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REJECT_RULE_NO=$(iptables -L RH-Firewall-1-INPUT --line-numbers | grep 'REJECT' | awk '{print $1}');/sbin/iptables -I RH-Firewall-1-INPUT $REJECT_RULE_NO -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT -m comment --comment "Permit HTTP Service"
2012-02-02 12:21:06
User: ajmckee
Functions: awk grep iptables
Tags: iptables kickstart
0
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Add an iptables rule on RH/CentOs before the reject

Rather then editing the /etc/sysconfig/iptables file, or during a kickstart doing some awk/sed magic, easily add a rule in the correct place within iptables

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sudo iptables -I INPUT -p tcp --dport 3000 -j ACCEPT
2011-12-16 10:39:13
User: Dhinesh
Functions: iptables sudo
Tags: iptables
-3
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open ports with iptables

This command will open tcp port 3000 in your machine

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iptables -P INPUT ACCEPT; iptables -P FORWARD ACCEPT; iptables -P OUTPUT ACCEPT; for table in `cat /proc/net/ip_tables_names`; do iptables -t $table -F; iptables -t $table -Z; iptables -t $table -X; done
2011-12-15 18:19:34
User: dash
Functions: iptables
Tags: Linux iptables
0
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Stop iptables completely

If you changed the default policy on any chain other than filter table chain's, this won't be enough.

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iptables -A OUTPUT www.baidu.com -p tcp -j REJECT --reject-with tcp-reset
2011-06-26 03:12:22
User: kev
Functions: iptables
Tags: iptables
-10
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stop children visiting sex sites:www.baidu.com

To save all rules so that they are not lost in case of a server reboot:

/etc/init.d/iptables save

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iptables -A INPUT -s 65.55.44.100 -j DROP
2011-05-23 08:32:47
User: igorfu
Functions: iptables
Tags: iptables
-1
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Block an IP address

Thanks to http://www.cyberciti.biz/faq/how-do-i-block-an-ip-on-my-linux-server/

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cd /etc/network/if-up.d && iptables-save > firewall.conf && echo -e '#!/bin/sh -e\niptables-restore < $(dirname $0)/firewall.conf' > iptables && chmod a+x iptables
2011-05-01 03:23:26
User: pkufranky
Functions: cd chmod dirname echo iptables iptables-save
Tags: sudo iptables
0
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Persistent saving of iptables rules

Should run with sudo

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iptables-save > firewall.conf; rm -f /etc/network/if-up.d/iptables; echo '#!/bin/sh' > /etc/network/if-up.d/iptables; echo "iptables-restore < firewall.conf" >> /etc/network/if-up.d/iptables; chmod +x /etc/network/if-up.d/iptables
2010-11-13 23:58:28
User: Alz
Functions: chmod echo iptables iptables-save rm
Tags: sudo iptables
0
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Persistent saving of iptables rules

a simple command in order to make iptables rules permanent, run @ sudo!

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iptables -A FORWARD -i br0 -m iprange --src-range 192.168.0.x-192.168.0.y -m iprange --dst-range 192.168.0.w-192.168.0.z -j DROP
2010-11-13 23:55:23
User: Alz
Functions: iptables
Tags: sudo iptables
0
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Cloack an IP range from some IPs via iptables

Destination IPs will become invisible to source IPs!

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-A INPUT -i eth1 -m mac ?mac 00:BB:77:22:33:AA -j ACCEPT
2010-01-31 15:34:31
User: 0disse0
Tags: iptables firewall
2
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How to stop MAC Address via IPTables

edit the /etc/sysconfig/iptables file and try to work whit this:

-A INPUT -i (interface) -m mac (mac address) -j ACCEPT/DROP

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watch --interval 0 'iptables -nvL | grep -v "0 0"'
2009-08-22 18:18:05
User: Code_Bleu
Functions: grep watch
Tags: grep iptables watch invert-filter
4
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watch iptables counters

This will allow you to watch as matches occur in real-time. To filter out only ACCEPT, DROP, LOG..etc, then run the following command: watch 'iptables -nvL | grep -v "0 0" && grep "ACCEPT"' The -v is used to do an inverted filter. ie. NOT "0 0"

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sudo iptables-save > /etc/iptables.up.rules
2009-08-19 14:55:05
User: kamiller
Functions: iptables-save sudo
Tags: iptables firewall
-3
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Save iptables firewall info

Stores the currently active iptables rules to a file that will be applied upon reboot

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sudo iptables-restore < /etc/iptables.test.rules
2009-08-19 14:38:08
User: kamiller
Functions: iptables-restore sudo
Tags: iptables
-2
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Update iptables firewall with a temp ruleset

If you don't save the rule set it won't be applied during a reboot

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iptables -t nat -A PREROUTING -p tcp --dport [port of your choosing] -j REDIRECT --to-ports 22
2009-06-18 17:38:59
User: brizznown
Functions: iptables
Tags: iptables nat routing
9
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Redirect incoming traffic to SSH, from a port of your choosing

Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be:

iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22

Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum).

My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels.

Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

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iptables -D fail2ban-SSH -s <ip_address_to_be_set_free> -j DROP
2009-05-08 19:22:15
User: mheadd
Functions: iptables
Tags: iptables fail2ban
3
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Get an IP address out of fail2ban jail

Removes an iptables rule created by fail2ban. This example shows how to remove a rule for an IP from the fail2ban-SSH chain. Can be used for any service monitored by fail2ban.

For more on fail2ban, see http://www.fail2ban.org/wiki/index.php/Main_Page

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iptables -F && iptables -X && iptables -P INPUT ACCEPT && iptables -OUTPUT ACCEPT
2009-03-27 15:03:54
User: lme
Functions: iptables
Tags: Linux iptables
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Disable all iptables rules without disconnecting yourself

This turns your iptables packet filter to a "Allow any from any to any" filter, so you can rule out any filtering issues when you have a problem to enable a connection from or to your host.

To re-enable it, run /etc/init.d/iptables restart

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