Creating a FreeBSD Jail

Introduction
Jails are a great way to secure your processes to a
[url=javascript:;]virtual[/url]
system. Though they have more overhead than chroot, (which basically just restricts the
[url=javascript:;]root[/url]
of a process) a
[url=javascript:;]jail[/url]
uses a virtual machine to house your process or processes. This means that far more restrictions can be placed on the jail, and there's no "breaking out" as can be done with chroot (see links in references).
A few notes first of all. It's very true what they say in the man page about it being easier to make a fat jail, and scale down to a thin one than vice versa. A few weeks of research (and many make worlds) have helped me discover that.
Also note that as of
[url=javascript:;]FreeBSD[/url]
5.4 (and likely 6.0) there is no IPv6 support for jails. This is unfortunate because jails tend to monopolize address space after making quite a few of them and address space is what IPv6 is all about. Sure there's NAT but everyone knows NAT is an ugly hack these days. I can only hope that IPv6 will be supported soon.
Jail Creation Techniques
From what I've seen there are three primary ways of creating jails.
MiniBSD
I've heard reports of people using [
https://neon1.net/misc/minibsd.html
MiniBSD] to do this, but I haven't had much luck with it, and I have yet to see a
[url=javascript:;]howto[/url]
explaining how they made it work, it's a great idea of making an initial thin jail but there's a million things that can go wrong since it's very minimal and the service(s) you are trying to run may have dependancy issues.
Using /stand/sysinstall
Other howtos tell to use /stand/sysinstall to go out to the net, download the system binaries, and install specific distributions from the installer. I've had little luck with this as well since you run into the problem of not having an interface set up for the installer to use. There's probably a way to do this but none of the howtos I tried did a very good job of explaining how.
Using make world
This is the way I'll use here in this tutorial and the way explained in the manpage. You can customize the make file to scale down your distribution and set some optomization flags for your system. The primary drawback is the time it takes to build the world which can be hours depending on your system.
Getting services to not listen to *
First off, we should make sure we get the system so that we have nothing listening on *, to check what what we need to modify issue this command
sockstat|grep "\*:[0-9]"
This should give you a synopsys of all the processes and
[url=javascript:;]ports

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