Squid is the most popular Proxy server for Unix like operating systems. It also used for web filtering. Its widely used for increasing web server speed by caching repeated data.
This tutorial helps you to install Squid proxy server on your Debian 9 Stretch system. Also provide basic configuration details of the Proxy server to allow traffic, restrict specific websites with keyword or domain names.
Step 1 – Install Squid on Debian
Login to your Debian 9 system using root or sudo privileges user. Then run the following commands on the console to install Squid on Debian 9 system from the default package repository.
sudo apt update sudo apt install squid
Step 2 – Configure Squid Port
Squid default runs on port 3128. It is your choice to keep running squid on default port or change it to some different port. To change port edit squid configuration file and changehttp_port value.
After making changing let’s restart Squid service to reload the configuration changes
sudo service squid restart
Step 3 – Allow All Traffic
Sometimes you are required to allow all traffic on your proxy server. In Squid server open Squid configuration file. Comment the http_access deny all line and add the http_access allow all entry this file.
http_access allow all #http_access deny all
Step 4 – 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 the 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 5 – 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 the 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.