• Squid caching web proxy
• apt-cacher caching apt proxy
• BIND9 caching/local DNS server

Installing the squid web proxy

apt-get install squid squid-prefetch

You will then need to configure the ACL to allow access through the proxy from the local network.

nano /etc/squid/squid.conf

visible_hostname server1     #Line added
...
http_port 8080     #Line changed
...
cache_dir ufs /var/spool/squid 2000 16 256     #Line changed
...
acl local src 10.0.1.0/255.255.255.0     #Line added
http_access allow local     #Line added

This configures the squid cache to listen on port 8080 instead of 3128, allows access from all IPs in the range 10.0.1.1 – 10.0.1.255, and sets the cache size to 2000MB. Then you need to restart the squid service:
/etc/init.d/squid restart

You can then configure your end users’ machines to use http://server1:8080/ as their internet proxy. I recommend setting this for insecure (non-SSL) traffic only as I have noticed some odd behavior with SSL proxying.

In Firefox this is dead-simple:

1. Open the Preferences window from the application menu on OSX or the Options window from the Tools menu on Windows.
2. Choose the Advanced section at the top, followed by the Network tab.
3. Click the Settings button under the Connection header.
4. Choose the “Manual configuration” radio button and enter http://server1:8080/ in the HTTP Proxy box.

Safari on OSX uses the system-wide proxy settings:

1. Choose System Preferences from the Apple menu
2. Click the Network item under the Internet & Network heading
3. Select your primary connection, wireless or wired, from the left-hand list and click the Advanced button
4. Choose the Proxies tab, choose Manually in the drop-down menu, check the box next to Web Proxy
5. Enter server1 in the first box and 8080 in the second box