May 25, 2005

OpenVPN for tunneling IPv6

One particularly useful OS X hack I've done recently was setting up openvpn as an IPv6 gateway for my machine at the office.

When I signed on with my company, they stuck a PC on my desk. I immediately wiped the drive and installed FreeBSD on it. FreeBSD is a good server-class OS, but the Mac has utterly spoiled me. So I actually bought myself a Mac Mini to use at work. It will be a while before there's any IT budget for a new machine for me, and in the meantime the mini is just fine, and it was very inexpensive, as things go.

I like IPv6 quite a bit. It's a great way to leave behind all of the restrictions and inconveniences that NAT impose. Anywhere I have a routable IPv4 address, I can set up 6to4 and do things like directly ssh to machines at home on the inside LAN.

Well, at work I don't have a public IPv4 address. To make a long story short, tunneling IPv6 over IPv4 just wasn't going to fly with the corporate firewall. I didn't want to make a big issue or anything, so I decided to tunnel over UDP. The easiest way to do that, of course, is with openvpn. So to make a long story short, I was able to set up IPv6 connectivity between my office machine and the house pretty easily.

Then along came the mac. What to do? Well, the mac is Unix-y enough that building and installing openvpn is no problem at all. Rather than fetch and install the LZO library, I simply added "--disable-lzo" to the configure command, then a make and make install. One last task is to obtain a tunnel driver for OS X.

Posted by nsayer at 02:44 PM | Comments (3)

Not much going on

I still have on my to-do list the conversion of the site to Serendipity. I would love to use WordPress, but they don't support PostgreSQL.

I've actually been doing lots of hacking lately on the house. I added a reverse osmosis system under the kitchen sink, then ran a branch from the output side of that over to the fridge and installed an ice maker. What struck me while I was doing all this was how little there was on the web about those subjects. I thought you could find anything on the Internet.

The RO system was straightforward enough. The whole system is piped with 3/8 inch and 1/4 inch Polyethylene tubing. The tubing connects from point to point with quick connect fittings (with the one exception being the connection to the water supply - that one is a compression fitting).

The hard part was figuring out how to connect the reject water output up to the sink drain. I wound up adding a dishwasher drain connection fitting to replace a piece of PVC under the side of the sink without the disposer. Then a baffling set of tubing and adapters took it from the barbed dishwasher fitting down to the 3/8" reject water tube. No sane plumber would have done it that way, but it doesn't leak, and I can get away with it because that water is not under pressure (the reject water hose comes from an air gap built in to the faucet and is gravity-fed to the drain).

After the RO system was installed and set up, I turned it off, emptied the tank and cut the supply tubing on its way to the faucet and put a T, a short piece of Polyethylene tubing and a valve, all quick-connect. Then I waited for the weekend so I could get a friend to climb under the house and run the polyethylene tubing from a hole in the sink cabinet over to the wall behind the fridge. I bought a small 'ice maker hookup box' from Home Depot to mount in the drywall behind the fridge. That was made with a 1/2" screw connection, but it was easy to add some adapters to turn that into another 3/8" quick connect fitting, ready to receive the 3/8" poly tubing. The "user" side of the box has a standard 1/4" compression fitting for soft copper pipe to the fridge.

It took a couple hours before I was convinced that none of the fittings were leaking. They warned against overtightening the copper compression fittings, but it turns out their warnings, IMHO, were overstated. I had to tighten those damn things pretty tight before they stopped leaking. The other leaky spot was the adapter from the 1/2" threaded copper valve to the quick connect adapter. You need lots of teflon tape for a plastic-to-copper screw connection, I guess.

My wife is exstatic about the whole set up. We have really good tasting water and ice cubes that don't make "floaties" in the water (or iced tea).

Posted by nsayer at 02:03 PM | Comments (2)