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Undo iptables modification

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http://unix.stackexchange.com – I ran the following iptables commands to create a blacklist rule but used the wrong port: iptables -A INPUT -p tcp --dport 22 -m state --state NEW -m recent --set --name SSH iptables -A INPUT -p tcp --dport 22 -m state --state NEW -j SSH_WHITELIST iptables -A INPUT -p tcp --dport 22 -m state --state NEW -m recent --update --seconds 60 --hitcount 4 --rttl --name SSH -j ULOG --ulog-prefix SSH_brute_force iptables -A INPUT -p tcp --dport 22 -m state --state NEW -m recent --update --seconds 60 --hitcount 4 --rttl --name SSH -j DROP How can I undo the above and then redo it for a different port? (HowTos)

Danial's picture
Submitted by Danial on 12/04/2012

Stories similar to Undo iptables modification

Part of a firewall on a server :

iptables -A INPUT -p tcp --dport 22 -m state NEW --state -m recent --set

iptables -A INPUT -p tcp --dport 22 -m state --state NEW -m recent --update --seconds 100 --hitcount 10 -j DROP

When I search online I always see NEW being used in that rule but I'm having a hard time understanding why ESTABLISHED and RELATED aren't being used.

Like this :

iptables -A IN

Prevent SSH attacks 34 weeks 6 days ago

I'm trying to setup iptables rules to only allow 3 attempts by an IP per minute to connect to the servir via SSH, and drop all the connections after to prevent SSH attacks; but it seems i'm doing something wrong!

-A INPUT -p tcp -m tcp --dport 22 -m state --state NEW -m recent --set --name DEFAULT --rsource -A INPUT -p tcp -m tcp --dport 22 -m state --state NEW -m recent --update --seconds 60 --h

This is the rule in iptables for stop sync_flood attacks:

iptables -A INPUT -m state --state NEW -p tcp -m tcp --syn \ -m recent --name synflood --set

iptables -A INPUT -m state --state NEW -p tcp -m tcp --syn \ -m recent --name synflood --update --seconds 1 --hitcount 60 -j DROP

Error:

iptables: Unknown error 4294967295

I don't know what exactly to do, this ocurrs when insert the last rule

I've setup IPTables with the following script...

Iptables recent module 1 year 10 weeks ago

iptables -A INPUT -p udp -m state --state NEW -m recent --set --name alimit --rsource

iptables -A INPUT -p udp -m state --state NEW -m recent --update --seconds 1 --hitcount 5 --name alimit --rsource -j DROP

it gives unknown error because cat /proc/net/ip_tables_matches

udp tcp owner state length ttl tcpmss multiport multiport limit tos icmp

Is there any alternative, since its disa

When I have send a request to an application running on a machine which following firewall rules are applied, it waits so long. When I have deactivated the iptables rule, it responses immediately.

I am trying to set up port forwarding with iptables.

I've read several stuff (including here on serverfault) but every example I try fails.

I have a Debian GNU/Linux box with a globally routed IP address, say 1.2.3.4.

I'm trying to find out why changing my default iptables policy is affecting what nmap sees when it scans my host.

Consider the following iptables setup:

iptables -F iptables -A INPUT -p tcp -s 10.1.0.0/20 --dport 22 -j ACCEPT

iptables -P INPUT ACCEPT iptables -P FORWARD DROP iptables -P OUTPUT ACCEPT

iptables -A INPUT -i lo -j ACCEPT iptables -A INPUT -m state --state ESTABLISHED,RELATED -j AC

open Ports in IP tables 3 years 16 weeks ago

Hi I would like to open some port from IN to OUT

pop3,smtp. whenever i tried to add some rules to existing iptables it gives me an error Applying iptables firewall rules: iptables-restore: line 21 failed

I am using the Cent OS 5.3

how do i open the ports?

INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0]