how to block mirc chatting, emailing, downloading

[biosfree]

hi there expert!!

im a newbie for linux(just stated this week), hope my questions are clear!
my school was supplied 22 pc. 20 students pc 1 teacher and another 1 server. all 20 studnets n teacher pc are windows xp, while serve is  linux (redhat professional workstation)

questions:

i want to block only for all 20 students pc from mirc chatting, emailing, downloading for a certain extent of time. full access for teacher.

i successfully installed dansguardian (recommended by sourcehttp://www.savs.hcc.edu.tw/~chuavv/articles/dansguardian-en.html) but i dunno what to do next. my student pc still can access.
tq

[Ricky]

Well..
it is very simple, you can use squid itself to do it effectively. First see this --> squid time acl
There you can specify range of ips by ip1 - ip5 etc.

[biosfree]

hemmm... means i can block it without danguardina.

anywhere i'll let u know if i succeed!!! tq....

[biosfree]

hemmm... it looks fine.....how then if i want to block them to download any file eg mp3 and chatting mirc, while at the same time they can surf internet.

[gauravbajaj]

Ok

Suppose u wana block download for tthe ip's ranges from 192.168.8.1-192.168.8.14
First make an acl
acl clients src      192.168.8.1-192.168.8.14

After that , make a  file in /etc directory and name it block
Just add as meny exetentions which u want to block ..i.e suppose u wana block exe and zip download

Just add the entries in that file  like this
.exe$
.zip$

Save the file and exit
After that just add a new acl name it download
 acl download url_regex -i  "/etc/block"
and just add this below line in last
http_access deny  clients  download
http_access allow all

Hope u get it

Gaurav

[biosfree]

well, im getting understand more on how to use acl in squid.
iv done with blocking ip and downloading.

can u help me next for:

block client from any chatting like mirc (something about port i assume), sending email like yahoo email, mssnger.. and at the same time they still can surf internet.

tq expert!!

[gauravbajaj]

Ya u can do it also for that u have to write acl in squid.conf filw..or u can use iptables and block the ports ..

Gaurav

[Ricky]

What you have asked simply needs few acl like blocking port for mirc etc, then blocking server like yahoo as you want to block its email or you can simply disallow yahoo mail server but allowing rest of yahoo site.

so this way deny whatever u want and at the end allow rest.