in 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.
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:
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 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)
How can I block access to a certain internet site using ufw? Let's say I want to block access to www.xxx.zzz (IP 1.2.3.4) to any program and user; using iptables I can do
sudo iptables -A OUTPUT -d 1.2.3.4 -j DROP how can I do that using ufw? if ufw can not do this, where should I put this rule to persist it over reboot, without interfering with ufw chains infrastructure?
I am trying to lock down our application and server with iptables. Anybody have any idea how to prevent accesses to the application from another application? Basically I opened up the ports 80 and 443 for the application server. However, the application points to other apps (ie. database, ldap). I want to limit what it can connect to or who can connect to it. Bascially I can limit who connects to the server itself but the application can still get input from outside servers.
in my network, users has total access to their PCs, so theres a problem to filter (URL, ports,etc.) their virtual machines installed (they can assign self any IP, e.g.)
Id thought about use the MAC prefix in VMware VMs (00:0c:29:*), but i can only found a way through DHCP, and this isn't a good solution (they can assign a static IP to workaround...)
It will be better using firewall (iptables), but I don't found the way to add rules based in MACs with wildcards.
At first I installed debian 5 and I want enter on my workgroup using windows XP PCs, in same time I want use firewall now when I stop firewall I can access on the pcs but when I start iptables and open port for samba such as 137,138,138 and 445 I can't access on any PC on work group this is the output of iptables - L command:
Code: Chain INPUT (policy DROP) target prot opt source destination ACCEPT all -- anywhere anywhere ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED ACCEPT udp -- anywhere anywhere udp dpt:netbios-ns state NEW ACCEPT udp -- anywhere anywhere udp dpt:netbios-dgm state NEW ACCEPT tcp -- anywhere anywhere tcp dpt:netbios-ssn state NEW ACCEPT tcp -- anywhere anywhere tcp dpt:microsoft-ds state NEW
Basically, I have a windows 2003 server virtual machine (vmware) inside Ubuntu 9.10.
The Ubuntu machine has IFconfig: Code: sam@sam-laptop:~$ ifconfig eth0 Link encap:Ethernet HWaddr 00:15:c5:b8:c8:8b UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) Interrupt:17
Why can't I ping or simply access the internal server on my ubuntu machine from a another computer on the 192.168.1.0 (slash)25 physical network? Do I need a bridge? Iptables?
I'm running an own PPTP Server, but I can't get it to access the internet. All my PCs at home run in the 192.168.0.0/24 net, the PPTP Server has local IP192.168.0.5 and remote IP 192.168.0.80-99. The router to the internet is at 192.168.0.1, and the IP of eth0 on the machine where the pptpd runs is 192.168.0.4. I want to be able to connect to the internet trough that VPN and access my local LAN servers (which works fine so far). I can ping internet and local IPs successfully, but can not access them with a browser, or connect to them in any other way. I have 'accepted' all in/output and forwards.
I am running a Squid proxy on the same machine, and if I do: iptables -t nat -A PREROUTING -j REDIRECT -i ppp0 -s 192.168.0.0/24 -p tcp --dport 80 --to-port 3128 I can access the internet through Squid, but of course Jabber/ICQ etc. Won't work then because it just refers port 80. But I want the PPTP Clients to connect to the internet directly, if I don't use that rule it's not possible to load any pages. But pinging works all the time. DNS is also working fine, but I can't even access webpages via IP directly. How can I allow the PPTP IPs 192.168.0.80-99 to get direct access to the Internet with Iptables?
I have a small home network with a router to the outside world and an ubuntu server through which traffic passes first.My ISP limits my download usage during the day, which traditionally has not been an issue, but now the children come in from school, boot up the internet and up goes my usage!Ideally I would like to be able to restrict them to IM and maybe certain specified URLs (I think the latter probably needs to use Squid though?). Once the download limits are lifted, I would like my iptables to allow HTTP, etc, but pretty much block most other things.
I have two sets of iptables currently to approach this issue, with a cron job that runs to swap between one and the other.Chains run in order, so if rule A says allow x, and rule B says drop all, then X should still be allowed. However, try as I may, this is not what happens in practice. I have even tried changing the overall order from ALLOW to DROP in FORWARD and then approach from the other angle. That didn't work either. *IS* it actually possible to block all but http / https and IM? These are myrules:
Code:
# Generated by iptables-save v1.4.4 on Sat Jan 9 19:15:49 2010 *nat :PREROUTING ACCEPT [583:45175] :POSTROUTING ACCEPT [694:60887] :OUTPUT ACCEPT [143:18642]
I 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.
I 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.
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)
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?
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.
I 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
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?
I 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:
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.