from: http://squid.visolve.com/squid/sqguide.htm
Squid - A quick start guide
Introduction
This document is a concise guide meant to step you through the basic steps needed to install and configure Squid. It is dedicated for beginners who want to get Squid running quickly in Linux. Use this only if you have quite a simple setup. For detailed configurations please have a look at our Configuration Manual
Step I - Downloading and compiling Squid
You can download squid source archive file as a gzipped tar ball of the form (eg.squid-*-src.tar.gz) available at http://www.squid-cache.org/ ;or from ftp://www.squid-cache.org/pub, Next you have to untar the file and change the working directory to squid-*
tar -xvzf squid-*-src.tar.gz
cd squid -*
Now enter the following commands in order to configure, compile and install squid
./configure
make
make install
This will by default, install into "/usr/local/squid". Type ./configure --help to view all available options.
Step II - Basic Configuration
Some basic Configuration is to be done in Configuration file. By default this file is in the following path "usr/local/squid/etc/squid.conf". In the configuration file uncomment and edit the following lines.
cache_dir
Set cache_dir to an area that has a large amount of hard disk space in order to devote to caching.
Cache_dir ufs /usr/local/squid/cache 100 16 256 is common.
http_port
Check http_port, 3128 is a default.
http_access
By default http_access is denied to all. You have to set ACL rules as per your requirements. This is important because it prevents people from stealing your network resources
cache_effective_user & cache_effective_ group
Set cache_effective_user and cache_effective_ group to a user and group. This user should have the permission to read and write in the cache directory and in the log files.
Step III - Custom configuration based on your network needs
For Configuring squid for proxy
By default, squid is configured in proxy mode. In order to cache web traffic and to use the squid system as a proxy, you have to configure your browser, which needs at least two pieces of information:
i. _____ the proxy server's host name
ii. ______ the port that the proxy server is accepting requests on
For Configuring squid for transparency
Using squid transparently is a two part process, requiring first that squid be configured properly to accept non-proxy requests (performed in the squid module) , and second that web traffic gets redirected to the squid port (achieved in three ways namely policy based routing, Using smart switching or by setting squid Box as a gateway).
Getting transparent caching to work requires the following steps:
i. ___For some operating systems, you have to configure and build a version of Squid which can recognize the hijacked connections and discern the destination addresses. For Linux this seems to work automatically. For BSD-based systems, you probably have to configure squid with the --enable-ipf-transparent option, and you have to configure squid as:
httpd_accel_host virtual
httpd_accel_port 80
httpd_accel_with_proxy on
httpd_accel_uses_host_header on
ii. __________ Next you have to configure your cache host to accept the redirected packets - any IP address, on port 80 - and deliver them to your cache application. This is typically done with IP filtering/forwarding features built into the kernel. In Linux they call this ipfilter (kernel 2.4.x), ipchains (2.2.x) or ipfwadm (2.0.x).
For Configuring squid for Reverse Proxy
To run Squid as an accelerator, you probably want to listen on port 80. And you have to define the machine you are accelerating for. This is done in squid module,
http_port 80
httpd_accel_host visolve.com
httpd_accel_port 81
httpd_accel_single_host on
httpd_accel_with_proxy on
If you are using Squid as an accelerator for a virtual host system, then instead of a 'hostname' here you have to use the word virtual as:
http_port 80
httpd_accel_host virtual
httpd_accel_port 81
httpd_accel_with_proxy on
httpd_accel_single_host off
Step IV - Starting Squid
After you've finished editing the configuration file, you can start Squid for the first time. First, you must create the swap directories. Do this by running Squid with the -z option:
/usr/local/squid/bin/squid -z
Once that completes, you can start Squid and try it out. Probably the
