I see many people find difficulty to configure SQUID proxy server for internet sharing in Linux. So i write rough steps. I write these steps on Fedora Core 3 and some commands may not work in other distros.
Also I use kwrite text editor to edit files ince many newbies don't know howto use my favourite "Unix Visual editor"
Lets Start:
Consider 2 Machines A and B connected by LAN card:
Machine A : Redhat linux | Fedora
Machine B: linux or Windows
Machine A Two Network cards. Plugin the CAT 5/6 cable of your broadband ISP in one LAN card and the other card connect your Machine B network card by another cable:
Note: Check this guide first for connecting two computers without hub or switch:
http://www.littlewhitedog.com/content-8.html
Boot Machine A with redhat linux and login root
Type startx to boot to graphical mode
Open terminal
I assume you choose the SQUID Proxy server package when you install Redhat/Fedora.
To check if squid is installed
type command
You should see something like depends on your version
If not download Squid from here:
Lets configure your network cards. Machine A has two NIC (Network Interface Card)
type command
This will open Netwok setup dialog. Check attached screenshot
My Realtek network card i.e eth1 is connected to my broadband ISP and the second card eth0 is connected to machine B's NIC i.e eth0.

On non Redhat Linux use command:
To configure eth0 back in terminal type command :
or sometimes you will also have to type to activate
similarly configure eth1 with IP settings provided by your ISP.
You may directly add entries like gateway etcin tis file:
Text editor opens the squid.conf file
Press Ctrl G and enter line no. 1674
Delete the comment sign " # " and Make entry like this:
Again Ctrl G and line 1837 and remove comment "#"
Ctrl G and line 53 and only remove comment " # "
Ctrl G and line 2080 remove "#" and "none" and make entry
Save the file and close.
In terminal type
and see only this message if you followed my steps correctly:
Now type command
To start this service everytime you boot machine A type command:
Scroll down till see:
Select and Check the above entry by hit spacebar and then quit.
Squid server now configures on Machine A
Alternatively on Non Redhat Linux use this comand:
All the Squid log files are located here:
Boot your Machine B into either Linux or Windows.
Configure your single network card i.e etho
in terminal type
Open your browser Firefox and go to Proxy setings and see screenshot:

~~~~~~~~~~~~~~~~~
Do same in Windows:
If you use Windows on machine A then use this nice simple shareware:
http://www.winproxy.net/
or other Solutions:
AnalogX Proxy: http://www.analogx.com/contents/download/network/proxy.htm
NAT32: http://www.nat32.com/
WinGate: http://wingate.deerfield.com/?affiliate=8626
bye.
Also I use kwrite text editor to edit files ince many newbies don't know howto use my favourite "Unix Visual editor"
Lets Start:
Consider 2 Machines A and B connected by LAN card:
Machine A : Redhat linux | Fedora
Machine B: linux or Windows
Machine A Two Network cards. Plugin the CAT 5/6 cable of your broadband ISP in one LAN card and the other card connect your Machine B network card by another cable:

Note: Check this guide first for connecting two computers without hub or switch:
http://www.littlewhitedog.com/content-8.html
Boot Machine A with redhat linux and login root
Type startx to boot to graphical mode
Open terminal
I assume you choose the SQUID Proxy server package when you install Redhat/Fedora.
To check if squid is installed
type command
rpm -qa squid
You should see something like depends on your version
squid-2.5.STABLE6-3
If not download Squid from here:
Lets configure your network cards. Machine A has two NIC (Network Interface Card)
type command
neat
This will open Netwok setup dialog. Check attached screenshot
My Realtek network card i.e eth1 is connected to my broadband ISP and the second card eth0 is connected to machine B's NIC i.e eth0.

On non Redhat Linux use command:
netconfig
To configure eth0 back in terminal type command :
ifconfig eth0 192.168.0.1 netmask 255.255.255.0
service network restart
or sometimes you will also have to type to activate
ifconfig eth0 up
or
ifup eth0
similarly configure eth1 with IP settings provided by your ISP.
You may directly add entries like gateway etcin tis file:
type > kwrite /etc/squid/squid.confkwrite /etc/sysconfig/network-scripts/ifcfg-eth0
Text editor opens the squid.conf file
Press Ctrl G and enter line no. 1674
Delete the comment sign " # " and Make entry like this:
acl unix.blachat src 127.0.0.1 192.168.0.0/255.255.255.0
Again Ctrl G and line 1837 and remove comment "#"
http_access allow unix.blackhat
Ctrl G and line 53 and only remove comment " # "
Ctrl G and line 2080 remove "#" and "none" and make entry
visible_hostname unix
Save the file and close.
In terminal type
squid -z
and see only this message if you followed my steps correctly:
Creating Swap Directories
Now type command
service squid start
To start this service everytime you boot machine A type command:
ntsysv
Scroll down till see:
[ ] Squid
Select and Check the above entry by hit spacebar and then quit.
Squid server now configures on Machine A
Alternatively on Non Redhat Linux use this comand:
chkconfig --level 235 squid on
All the Squid log files are located here:
cd /var/log/squid/
Boot your Machine B into either Linux or Windows.
Configure your single network card i.e etho
in terminal type
ifconfig eth0 192.168.0.2 netmask 255.255.255.0
service network restart
Open your browser Firefox and go to Proxy setings and see screenshot:

~~~~~~~~~~~~~~~~~
Do same in Windows:
If you use Windows on machine A then use this nice simple shareware:
http://www.winproxy.net/
or other Solutions:
AnalogX Proxy: http://www.analogx.com/contents/download/network/proxy.htm
NAT32: http://www.nat32.com/
WinGate: http://wingate.deerfield.com/?affiliate=8626
bye.