Book Image

Squid Proxy Server 3.1: Beginner's Guide

Book Image

Squid Proxy Server 3.1: Beginner's Guide

Overview of this book

Squid Proxy Server enables you to cache your web content and return it quickly on subsequent requests. System administrators often struggle with delays and too much bandwidth being used, but Squid solves these problems by handling requests locally. By deploying Squid in accelerator mode, requests are handled faster than on normal web servers making your site perform quicker than everyone else's! Squid Proxy Server 3.1 Beginner's Guide will help you to install and configure Squid so that it is optimized to enhance the performance of your network. The Squid Proxy Server reduces the amount of effort that you will have to put in, saving your time to get the most out of your network. Whether you only run one site, or are in charge of a whole network, Squid is an invaluable tool that improves performance immeasurably. Caching and performance optimization usually requires a lot of work on the developer's part, but Squid does all that for you. This book will show you how to get the most out of Squid by customizing it for your network. You will learn about the different configuration options available and the transparent and accelerated modes that enable you to focus on particular areas of your network. Applying proxy servers to large networks can be a lot of work as you have to decide where to place restrictions and who should have access, but the straightforward examples in this book will guide you through step by step so that you will have a proxy server that covers all areas of your network by the time you finish the book.
Table of Contents (20 chapters)
Squid Proxy Server 3.1 Beginner's Guide
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Time for action – using a request protocol to construct access rules


Let's say we want to deny all FTP requests from a particular subnet, known as, research labs. The configuration should look similar to the following:

acl ftp_requests proto FTP
acl research_labs src 192.0.2.0/24
http_access deny research_labs ftp_requests

The previous configuration lines will instruct Squid to deny all the FTP requests from the network 192.0.2.0/24.

Note

Please note that some firewalls block active FTP by default. Please check http://www.ncftp.com/ncftpd/doc/misc/ftp_and_firewalls.html for more information.

Apart from the previously mentioned standard schemes, we have a Squid specific URL scheme called cache_object, which is used for the cache manager (cachemgr) interface. By default, the cache manager can only be accessed from the Squid proxy server itself because of the following code in squid.conf:

acl manager proto cache_object
acl localhost src 127.0.0.1/32
http_access allow manager localhost
http_access...