Most people use a NAT router at home for connecting to the Internet, and most consumer-grade NAT routers offer some limited version of DHCP for automatically handing out IP addresses to desktops and laptops and game consoles and smartphones and some limited version of DNS for making sure all the devices on the network know what all the other devices are called. However, the feature set and functionality of these cut-down DHCP and DNS instances are almost always too limited to handle more than the simplest of network designs; sometimes, you need to be able to do more. For example, if you wanted to set up a separate DHCP zone for handing out addresses to untrusted wireless clients versus trusted clients, or if you wanted to do something more awesome like implement the Upside-Down-Ternet, you’d need something a lot more configurable than the little NAT router’s applications.

There are lots of options, but it’s easiest to just pull out the big guns and set up BIND9, the current version of the DNS software that powers the Internet, along with the ISC’s DHCP server. DNS and DHCP are like peas and carrots, as the saying goes—DHCP hands out the addresses, but doesn’t communicate to other network hosts who has what address; DNS knows how to correlate names to addresses but doesn’t hand out addresses itself. In this post, we’ll set up DNS and DHCP on Ubuntu, and then configure them to work together.

(NB. This blog entry ended up being bloody huge, because I don’t just list the configuration options to set but rather go into detail on what each one does. I’d intended to bang the post out in a single evening, but instead it’s taken a couple of hours over three days to complete. I hope it is informative and helpful!)

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This is an old post. It may contain broken links and outdated information.

The first thing I ever saw of Minecraft was this video of an impossible waterslide which stretched up across the sky and down through footless caverns. I was entranced, and started playing shortly after that. Minecraft is primarily a sandbox game where you dig for resources and build things, all in glorious faux 8-bit graphics. Of late its creators have tried to turn it into a really bad Zelda clone, but fortunately it’s possible to ignore all the worthless stupid shit they keep adding and instead play it in the proper manner. It can be played single- and multiplayer, and while I normally hate playing with anyone online, Minecraft is my exception.

In October of 2010 I decided to download the Minecraft server application and take a stab at running my own Minecraft server, so that my buddies and I could have a private place to build things without worrying about random crazy people from the Internet kknocking down our sandcastles. There were some errors along the way, but I’ve settled on some guidelines and methods that have worked out very well for me.

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This is an old post. It may contain broken links and outdated information.

All the cool kids have web servers, but all the REALLY cool kids have web servers with the ability to send e-mail. In days of yore, when dragons roamed the Internet and a web page with a graphical background was considered a novelty, sending e-mail from your home was as easy as setting up sendmail (or your preferred MTA) and letting ‘er rip. Things are different these days, though, as spammers long ago ruined it for everyone and made doing your own e-mail a lot more difficult.

If you’re doing your web hosting through an actual hosting provider, then chances are you already have some avenue available for your web server or its applications to send e-mail; if you’re hosting out of your basement or closet, though, like I am, it can be a little more complicated. The first obstacle is that most ISPs will block the standard SMTP TCP ports; even if you get past that (by having an unblocked business-class connection, for example), damn near every operating e-mail system in the world blacklists the IP address ranges used by ISPs for customer connections, in order to stop infected home PCs from drowning them with viagra spam.

Here again spammers have peed in the pool, because no mail server will just happily relay messages.

The solution is mail relaying, where you send e-mail to a trusted e-mail server, which then sends it on to your recipient. Here again spammers have peed in the pool, because no mail server on the Internet is set up to just happily relay messages—in fact, any mail server that is configured as a so-called “open relay” will quickly find itself blacklisted by every other mail server.

But there is an easy way that your web server and its appliations can send e-mail outside of your LAN, and that way is to relay your mail through Google. Specifically, through a Google Apps Standard e-mail address.

This is a tutorial that’s been done elsewhere in lots of different ways—googling around for “postfix gmail relay” or “relay postfix through google apps” will net you scads and scads of results. I’m going to add to the pile by going through the method that I settled on. I was interested in setting up e-mail because I wanted to be notified of changes to the Bigdinosaur.org Minecraft wiki, and DokuWiki has a nice customizable notification system.

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