Blocking yahoo and Rediff bol

satish · 11-01-2006, 07:13 AM

i have Redhat 9 server in my office.i want to block yahoo and rediff bol in only 3 system these ip are given below

192.168.1.181
192.168.1.183
192.168.1.105

spectra · 11-01-2006, 08:32 AM

You need to use iptables which is the admin tool for the majority of firewall related tasks and NAT in Linux. You can find HOWTO's on google quite easily, the exact command you require should be:

iptables -A INPUT -p tcp -i <ethX> --dport <port> -s <IP Address> -j DROP

Where <ethX> is the interface which will probably be ppp0, eth0 or eth1, <port> is the port you want to drop. I think 5050 is the one for Yahoo and the -s flag sets the <IP address> which you obviously know.

Personally I would use:

iptables -A INPUT -p tcp -i <ethX> --dport <port> -m mac --mac-source <MAC Address> -j DROP

Which does the same but by MAC address. I'm pretty certain this should work but I havent tried the -m flag with the INPUT chain.

Dave

amitsharma_26 · 11-24-2006, 11:39 AM

For blocking rediff bol messenger via squid for your three clients,

Code:

acl these-ip 192.168.1.181/255.255.255.255 192.168.1.183/255.255.255.255 192.168.1.105/255.255.255.255
acl rediff-block url_regex gatekeeper.rediff
http_access deny rediff-block these-ip