Networking :: Using Iptables To Block IP Addresses Automatically?
Dec 7, 2009I want to use iptables to automatically block all IP addresses who send UDP packets with length 11 more than 3 times per 10 seconds.
View 1 RepliesI want to use iptables to automatically block all IP addresses who send UDP packets with length 11 more than 3 times per 10 seconds.
View 1 Repliesassist me in using the iptables firewall to block all incoming mail traffic (SMTP port 25) except that of a certain IP(s)? the situation is that we have a server that we only want to receive mail from a particular sender.
View 1 Replies View Relatediptables and multiple public-facing IP addresses. With the current setup I have a public-facing firewall with iptables which will then forward traffic to a LAN IP. I will hopefully be allotted 1 private IP per public IP, which I hope will make this much more simple. For example, I have server A with the LAN IP of 10.0.0.1 which I would like to have traffic forwarded from 5.0.0.1, the public IP. I also have server B with LAN IP of 10.0.0.2 which I would like to have forwarded from 5.0.0.2, the second public IP. From what I have read and understood, this should be a simple task, however I would just like to double check to make sure that it is in fact possible, and if so, how would it be recommended that I go about doing so. Essentially, I need to forward each public IP to a corresponding LAN IP with all ports.
View 3 Replies View Relatedin my office i have to block all messenger like yahoo messenger, windows live messenger, i have to block websites like www.yahoo.com, some more web sites. i need guidance through which i can accomplish this task through ip tables or through squid server. i can use squid but i had heard that squid blocks pop and smtp also. squid creates some problem in receiving and sending email. i am using red hat linux 4 box and installed squid having two ethernet card 1 is connected to adsl line and 2 is connected to switch. all clients will have proxy address of this linux box. guys need ur help ASAP.
View 2 Replies View RelatedJust wondering if it is possible to block web access on a certain ip address with iptables.
Iv seen guides for blocking web traffic on a whole network but i want to just block a single host from accessing the web.
I have a server with slackware 12 and i try to block 2 web sites but without success. I write in iptables rules /etc/iptables.conf
iptables -A INPUT -s web.org -j DROP
iptables -A OUTPUT -d web.org -j DROP
but no effect. What rule i must write to block url`s?
I have the requirement that if our website receives 20 or more requests within 60 seconds, to block the offending IP address for 5 minutes, then allow them access again. My only certain mechanism to do this is iptables. I wrote the following series of commands:
iptables -N RATE_CHECK
iptables -N DOSAttack
iptables -N RemoveBlock
[code]...
I am limited in my testing, but the little I have been able to test seems to be having no effect. will the above commands have the desired effect.
I Need to know how to block this applications using iptables or ROPE scriptable Method..?..
1.Web navigation
2.Electronic mail
3.FTP transfers
4.Video traffic (multicast video stream and unicast video stream)
5.VoIP service
6.Instant Message (MSN and yahoo messenger�etc)
7.Management service (TR-069 and SNMP)
I need to configure iptables to block incoming traffic (except specific ports), but allows all outgoing traffic.
I am able to block incoming traffic, but doing so also prevents outgoing traffic (tested by telnet [URL] 80)
The following was used:
iptables -A INPUT -p tcp --dport ssh -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j ACCEPT
iptables -I INPUT 1 -i lo -j ACCEPT
iptables -A INPUT -j DROP
Also, even allowing NOT SYN requests still prevents outgoing traffic.
iptables -I INPUT 1 -p tcp ! --syn -j ACCEPT
Another point:
# modinfo ipt_state
modinfo: could not open /lib/modules/2.6.18-028stab070.14/modules.dep
How to install ipt_state module on ubuntu?
I Need to know how to block this applications using iptables or ROPE scriptable Method..?..
1.Web navigation
2.Electronic mail
3.FTP transfers
4.Video traffic (multicast video stream and unicast video stream)
5.VoIP service
6.Instant Message (MSN and yahoo messenger�etc)
7.Management service (TR-069 and SNMP)
now I have managed my rsyslogd to log the firewall into a separate file I would like to use a script which looks into this file for intruders which for example try to ping, telnet, ssh, rdp etc into my dsl connection.And then use a kind of app or firewall on my ubuntu server to block them.Yes my firewall logs them but does not block them if the policy is enabled, so they have access on through the firewall and the connect to my server but I only want some known IP addresses have access through it and this I cannot program in the firewall so I have to use some extras.Or am I thinking way to far and is there a better solution with IPtables or app?Is it possible to watch tcp connections between the firewall from outside IP addresses and the ubuntu server?
View 7 Replies View Relatedso the firewall rules I am currently using are displayed below.
Code:
# DROP ALL FORWARDED PACKETS
iptables -P FORWARD DROP # DROP ALL PACKETS
# ALLOW DHCP THROUGH THE FIREWALL
[code]....
whether iptables logs can be set to automatically resolve IP addresses? I am running the firewall on a network with DDNS/DHCP, and this ability would really help quickly identify hosts with suspect traffic.Failing this, I guess the simplest solution will be to simply set static addresses!
View 1 Replies View RelatedI'm trying to limit access to port 8443 on our server to 2 specific IP addresses. For some reason, access is still being allowed even though I drop all packets that aren't from the named IP addresses. The default policy is ACCEPT on the INPUT chain and this is how we want to keep it for various reasons I wont get into here. Here's the output from iptables -vnL
[Code]...
Note the actual IP we are using is masked here with 123.123.123.123. Until I can get everything working properly, we're only allowing access from 1 IP instead of 2. We can add the other one once it all works right. I haven't worked with iptables very much. So I'm quite confused about why packets matching the DROP criteria are still being allowed.
Is this how I would do that?
iptables -A INPUT -p tcp --destination-port 21 -d ! 168.192.1.2 -j DROP
This should block all incoming connections on port 21 from 192.168.1.2, correct? Thus preventing that IP from logging into my FTP.
What i wanted to do was block everything from getting in my pc but still be able to surf the web and still use instant messenger.
View 2 Replies View RelatedI want to block all outgoing traffic with iptables and only allow a few specific websites. I would like to get the code to do so and also to revert the changes in case I want to unblock them.
View 1 Replies View RelatedI have blocked below IP by using iptables command in RedHat Linux 4.0.
Code:
iptables -A INPUT -s 192.168.0.85 -j DROP
It's now totally blocked and can't get access into web or internal network. how I can un-block that IP, so that it can again starts it's normal operation.
Currently I have 2 Lan card in My System one for communicate client pcs (Lan card Ip 192.168.1.100) and other for Internet (Lan card ip 192.168.0.100.) All client pcs are in 192.168.1.0 Subnet Here i implement my system as router through iptables all clients are communicate through only 192.168.1.100 (clients default gateway also 192.168.1.100) Now no problem for forward rules when my system is active all clients are get internet.
Output of iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
[code]....
Now i want to block some ip address and port ways i tried lot of things in internet when i type iptables -A INPUT -s 192.168.1.150 -j REJECT (i found in internet it will block that ip address for getting internet and any access through my sys)
Now th Output
Chain INPUT (policy ACCEPT)
target prot opt source destination
REJECT all -- 192.168.1.112 anywhere reject-with icmp-port-unreachable
[code]....
it will block icmp protocol only I want to know how block ipaddress and port address ways...
Currently I have 2 Lan card in My System one for communicate client pcs (Lan card Ip 192.168.1.100) and other for Internet (Lan card ip 192.168.0.100.) All client pcs are in 192.168.1.0 Subnet
Here i implement my system as router through iptables all clients are communicate through only 192.168.1.100 (clients default gateway also 192.168.1.100) Now no problem for forward rules when my system is active all clients are get internet.
Now i have problem with blocking UDP protocols i tried lot of things in net iptables -A INPUT -s 192.168.1.0/255.255.255.0 -p UDP -j DROP
But it's not blocking UDP protocols (i change UDP to ICMP Protocols then icmp is blocked every ip address)
My VPS host a mail, blog and web site. So i want to block port i not use. The port that i use is 80,21,2022,443. The other port will be drop. I want to block bad packet and all packet that not related. Can anyone how to write in iptables?
View 2 Replies View RelatedDoes anybody know how to block HotSpotShield in squid or iptables?
View 2 Replies View RelatedI try to create some rules to detect an outgoing traffic from my debian jessie that is not from my IP or loop.
#!/bin/bash
/sbin/iptables -N C_OUT_N_LOCAL
/sbin/iptables -N C_OUT_N_LOCAL_LO
/sbin/iptables -A C_OUT_N_LOCAL -m limit --limit 2/min -j LOG --log-prefix "PK: output not local : " --log-level 4
LO_IP="127.0.0.1"
MY_IP="192.168.0.4"
/sbin/iptables -I OUTPUT -p ALL ! -s $LO_IP -j C_OUT_N_LOCAL_LO
/sbin/iptables -A C_OUT_N_LOCAL_LO -p ALL ! -s $MY_IP -j C_OUT_N_LOCAL
I have a Suse 10.3 router with 4 network cards. 1 is to connect to the big network and thereby also the internet, 2 are for 'client' subnets and I want to use the last one as a DMZ. In this DMZ will be a web server which has to be accessible from the other 2 subnets and from the big network. I could do it with a few simple clicks in Yast firewall, but I have some issues with this firewall and there for I want to use it as minimal as possible, using Iptables.
So now I'm struggling a bit with Iptables. Basicly what I'm looking for is how to block all ports but 80 in this last subnet with iptables.
How can I block all ports except
ssh (port 22)
httpd (port 80)
using iptables and iphains?
how to block all ports except pop,pop3,smtp in nat using iptables in squid on redhat A3
View 2 Replies View RelatedI would like to allow incoming and outgoing connections when I'm connected to a wired connection, but drop it otherwise. I noticed that ufw can't block outgoing traffic because of will I give iptables a try. I'm unsure if dropping packages that are outgoing will work, the rule after the block rule will allow all outgoing connections.
This what the rules are intended to do, unsure if that is actually the case. Allow all loopback traffic. Allow ping replys Allow incoming on port 12345 if eth0, deny otherwise. Allow outgoing on port 12346 if eth0, deny otherwise.
Code:
iptables -A FORWARD -j DROP
iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -p icmp --icmp-type 0 -s -m state --state ESTABLISHED,RELATED -j ACCEPT
[Code]....
I keep getting hundreds of SSH failed logins per day. Is there a way with iptables, i can say if a user connects too to port 22 over 8 times in 10 minuntes, then block them for an hour?
View 7 Replies View RelatedI run a small home server (Debian 4), which acts as my gateway to the internet (ie, firewall) and runs a web server, dhcp, dns, and acts as a file server to the rest of the machines on my home network. Now I know it's never a smart idea to have all those services running on the same machine that is acting as a firewall, but I don't fancy running multiple servers just for home use, as it's mainly allowing me to learn system administration.
I noticed a few days ago that my internet had become unbearably slow, to the point where I could sometimes not load web pages. I spent a while searching through log files on my gateway, to try and find out what was eating up all of my bandwidth. When I came to apache's access.log file, I was confronted with this:
Code:
204.45.41.82 - - [17/Oct/2010:06:25:10 +0100] "GET http://vewice6.nightmail.ru/marriott-grand-cayma.html HTTP/1.1" 200 36921 "-" "Mozilla/4.0 (compatible; M$
204.45.41.82 - - [17/Oct/2010:06:25:11 +0100] "GET http://malaysiapodcaster.blogspot.com/2006/05/blog-post_11.html HTTP/1.1" 200 58681 "-" "Mozilla/4.0 (com$
[code]........
Multiple requests to my server, for totally random websites. I didn't even know it was possible to make those types of queries to a webserver. The only thing that is on the web server is a browser based torrent client. I have only shown a small snippet of the log file, but there are around 90k lines to different web addresses, from many different IPs. What I want to know, is what is happening? :S Why is someone querying MY web server, for web sites totally unrelated to it? And most of all, how can I stop it. My initial was to try and use iptables to block multiple requests from the same ip within a certain time frame, which I think would work as the server shouldn't really get many queries from external networks.
I'm running vsftpd on a Ubuntu 10.4 server and noticed that my ftp server is getting brute force attacked. I usually check for the IP address and manually add it to my Smoothwall firewall but I was wondering if there is a way for vsftpd to automatically block denied access after certain number of attempts. Let's say 5.
View 2 Replies View Related