Squid is the most popular Proxy server for Linux systems. It also used for the web filtering. Its widely used for increasing web server speed by caching repeated data.
This article will help you to Install and Configure SQUID Proxy Server on CentOS, Redhat and Fedora Linux systems.
Step 1 – Install Squid
Squid packages are available in default yum repositories. Execute below command on your server to install SQUID proxy server.
yum install squid
Step 2 – Setup SQUID Service
Squid default runs on port 3128. If you want to start squid on different port, Edit squid configuration file and change http_port value. For example we are changing squid to run on port 8080.
After making changing let’s restart Squid service to reload the configuration changes
service squid restart
Step 3 – Block Specific Website with Squid
Let’s start with the additional configuration like blocking any website using squid proxy server. Add below rules to block specific website before any allow all rules. Below example will block yahoo.com and www.rediff.com.
acl blocksite1 dstdomain yahoo.com acl blocksite2 dstdomain www.rediff.com http_access deny blocksite1 http_access deny blocksite2
If you have a long list of domain names, Create a file /etc/squid/blockwebsites.lst and put domain names one per line and add below rule in squid configuration file.
acl blocksitelist dstdomain "/etc/squid/blockwebsites.lst" http_access deny blocksitelist
blockwebsites.lst file content example:
# cat /etc/squid/blockwebsites.lst yahoo.com www.rediff.com
Step 4 – Block Specific Keyword with Squid
Add below rules to block specific website before any allow all rules. Below example will block all pages having keyword yahoo or Gmail.
acl blockkeyword1 url_regex yahoo acl blockkeyword2 url_regex gmail http_access deny blockkeyword1 http_access deny blockkeyword2
If you have a long list of keywords, Create a file /etc/squid/blockkeywords.lst and put keywords one per line and add below rule in squid configuration file.
acl blockkeywordlist url_regex "/etc/squid/blockkeywords.lst" http_access deny blockkeywordlist
blockkeywords.lst file content example:
# cat /etc/squid/blockkeywords.lst yahoo gmail facebook
Congratulation’s you have successfully install and configured Squid proxy server. Read next article to Configure Squid for Mac Address Based Filtering.