am i have to write down on /etc/services all the port that i like to block (i.e Yahoo messenger, MSN, IRC)
what port windows messenger is (enable by default on Window$ XP) ? i'd like to block through my firewall ?
thanks for your concerned
No, you should not change anything in your /etc/services file.
Most applications use this file only as a reverse look-up for which service name a certain TCP/UDP port is using. However, some NetApps uses this file to enable certain services.
If you wish to block some services you should/shall set up a block rule in your firewall.
As for the default port on MSN it is 1863, however, in the newer versions of MSN you are able to use HTTP postings to MSN as well. Which is quite hard to block by port or content. What you could do is to get a list on all "login" servers at MSN, and block those IP's in your firewall, that would pretty much shut down all MSN activity at your network.
Haiii.....I would like to know how to set up a block rule in iptables, i want to block some port numbers how can i do. I dont remember the command for it.......Please help.
I'd recomend using a frontend like webmin's firewall module, setting up all the rules manually is a pain (to change a rule via the 'iptables' command one has tpo pop all following rules, and then push the changes rule and the rest, damn stupid design, ne?), but with a frontend it's as easy as chaning a rule and it's done :)
the Default port of MSN is TCP/UDP 1863. i agree to that to use webmin to block it in iptables..and u might need the use of squid to block it,in short u need squid and iptables in order to block thats ports successfully especially yahoo. it uses a some ports even port 80 they use it. gather all list of ports u want to block and its wildcard sites, then plan the blocks...hope this will help...