Here is a VMware virtual appliance for DansGuardian on CentOS 5.2

The virtual appliance is composed of:
* CentOS 5.2
* VMware Tools
* Squid 3
* DansGuardian

Click on below links to download the virtual appliance.
1. centos-dansguardian-virtualappliance.vmx
2. centos-dansguardian-virtualappliance.vmdk

You can use this virtual appliance to do things like:
1. Do phrase matching, PICS filtering and URL filtering.
2. Restrict list of sites.

Username: root
Password: dans12

Steps to configure the virtual appliance:-
1. yum install squid*

2. /etc/rc.d/init.d/squid restart

3. Enable packet forwarding in /etc/sysctl.conf. Set net.ipv4.ip_forward = 1.

4. Make changes to /etc/squid/squid.conf. A copy of the original files are kept with the extension .orig *

5. Yum install dansguardian or do the ./configure if you want the 2.10.0 version

6. Make changes in /etc/dansguardian/dansguardian.conf. A copy of the original files are kept with the extension .orig *

7. Enable A. squid B. iptables C. dansguardian using ntsysv

8. Configure iptables to redirect requests from port 80 to port 8080 using following commands**:-
a. iptables -t nat -A PREROUTING -i eth1 -p tcp -m tcp -d ! <ip-address-of-i-interface> –dport 80 -j REDIRECT –to-ports 8080
b. iptables-save > /etc/sysconfig/iptables
c. service iptables restart

Improving the performance of squid:
Edit squid.conf with these settings:-
maximum_object_size_in_memory 8 MB earlier it was 8KB
cache_mem 800 MB earlier it was 8 MB

Improving the performance of dansguardian:
Edit dansguardian.conf with these settings:-
urlcachenumber = 5000  (default is 1000)
urlcacheage = 9000 (default is 900)

* The difference between original and copied file can be seen using “diff orig_file new_file”
** This will make sure that requests for web sites hosted on this server will not get redirected to port 8080

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