All-in-one guide for those looking to create a low cost firewall appliance
Setting up your own OpenVPN Firewall appliance with FreeBSD (scribd.com)
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- OpenVPN – getting it running
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- Setting up a LAMP Server on FreeBSD
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or install pfSense, end up with the same end result, and save yourself a ton of time. :)
You can learn a lot by doing it manually though, if you have the time to spare.