Charles Curley's Weblog

Living in a small town in Wyoming, I often face limited choices at the supermarket. We have two, but they're both small and they both tend toward the lowest common denominator. So often I can't get things I want here, or I can but it just isn't fresh.

The solution to that problem is, of course, to shop in the Big City. The best time to shop at a Walmart Super Center is at 05:00 when it isn't crowded. But how do you get refrigerated or frozen stuff home?

The solution to that problem is a refrigerator. I'm not talking about a cooler filled with ice. Ice melts, coolers leak, etc. A cooler cannot guarantee a given temperature. Nor do I mean a cooler fitted with a thermoelectric cooler. They get at best a 40° Fahrenheit difference in temperature (often less), which makes them useless if the temperature in the car is above 90°. I'm talking about a real refrigerator with a compressor, temperature controls, and lots of insulation.

I'm talking about the Model FP430 EdgeStar Portable Fridge/Freezer. I've had one for a while, and it works quite well. I buy a half of a buffalo from time to time, and once in a while I need an overflow freezer. My EdgeStar has done that duty very well. When it's not doing that, and temperatures are warm, it sits in the back of the car.

I've had one problem with it. Hidden in the 12 volt plug is an odd size fuse. I managed to blow that fuse, and could not find a replacement. The workaround is to splice a blade fuse holder into the line, and replace the fuse in the plug with an aluminum dummy.

I have a 2009 Subaru Forester, and I'm very pleased with it. It has three power point (cigarette lighter to us dinosaurs) sockets, one of which is in the cargo bay. That one provides up to 20 amps, which is what the EdgeStar's fuse is rated for. The power points are controlled by the ignition switch, which is a good thing: you can't run the battery down by leaving the fridge plugged in. The bad news is that you really can only run the fridge from the car when the engine is running, i.e. when you're driving.

There are two ways to work around the latter. The simplest is to plug the refrigerator into the mains when you aren't driving it. That helps conserve the car's battery. That's great for pre-cooling before you load up and depart. It does not work very well in a Walmart parking lot. Nor does it work when you go camping. At least, not where I go camping.

By the way, if I do plug the car into the mains for any reason, I loop part of the extension cord through the driver door handle or over the driver's windshield wiper so I don't forget it's there three days later….

The solution to that is a deep cycle battery such as those sold for marine and RV auxiliary power, or for solar power installations. You also need an alligator clip to power point cable, which most automotive stores carry. Add a fuse to that cable. You should put the battery inside a battery container, partly to contain leaks, but more to have a cover on the battery's terminals.

For charging the battery from the mains, a 1.5 amp trickle charger does just fine. For faster charging, get a higher capacity charger. However, the faster the charger the more likely it is to damage the battery by charging too fast. I find a 1.5 amp charger will recharge my battery in 24 to 36 hours.

Now, should you live in an area prone to power outages, you have a battery backed up refrigerator or freezer. The fridge will automatically fail over to the battery should it lose power from the mains.

You can get solar panels. A 5 watt panel does not require a charge controller, but it simply will not keep up with the fridge. 60 watt panels are large enough to be awkward in a car, and require a charge controller. But one such should extend the battery charge for quite a while. You want a heavy duty extension cord long enough so you can park in the shade but still put the panel out in the sun, but not so long that the voltage drop kills you.

The next trick is charging the battery while the car is moving. Get a vehicle to vehicle battery booster cable. These go from power point to power point. I use a Black&Decker Simple Start, catalog number BBC2CB. It has smarts on it, and delivers about 8 amps. Buy a twofer, and then you can leave the whole setup plugged in, and you don't have to muck with it while you are traveling or camping. They also double as part of one's emergency kit.

I took this setup with me last October to visit a friend who lives off-grid in Arizona. I was there for three days, and didn't run my car engine. Temperatures in the car got to over 95° daily. The fridge was still running from the deep cycle battery after those three days.

People act as though remote work is some new invention. Especially managers who think the only way to measure productivity is to look into your cubicle to see if your feet are on your desk.

Nope, remote work has been around for centuries, millennia, longer. Colonial ventures like the East India companies raised it to a peak. It's just that now with the Internet we can communicate and co-ordinate much better than earlier remote workers could.

I have to wonder... I signed up for Technorati, which had its own glitches. I then "claimed" my blog. My account page indicates that on December 2, they found the tokens they wanted on this blog. My claim is still, six weeks on, awaiting review.

Methinks Technorati could use some competition.

Update, 2010-01-28: Now I have the same message, "We have successfully crawled your blog and found the claim token, and your claim is now awaiting review. You may now remove the claim token from your feed." That's now dated January 19th, the day after I posted the above. Coincidence?

Update, 2010-03-01, three months on: I just got an email saying that Techorati had a problem with my blog. It appears they can't find the claim token. Well, doh! They said I could take it out (see the update above), so I did. Did they expect me to leave it there or something?

And, as further evidence of stupidity, there's nothing on the claim status page that tells me how to re-install the token. It's as simple as "Here, put this HTML on your blog's boilerplate...." or "See this page for complete instructions"

I don't need this level of incompetence. Technorati can stuff it in a very dark place, where they might find their brain.

I run my own DNS servers at home. I have to, or I'd never find some of the computers on my home network. Running your own DNS server means occasionally updating the list of root servers.

DNS works by querying a name server. If the name server is authoritative for the zone you are interested in, it responds and that's that. If it isn't, it has to query the authoritative server and relay the response to the inquiring client. In order to do the latter, it has to locate the authoritative server. It does that by querying one or more "root" name servers. Root servers come and go, which means you need to fetch a list of them from time to time. Monthly is probably overkill.

Being the lazy bum that I am, I wanted to automate doing that.

It's easy enough to set up a monthly fetch of the file, using crontab and wget. Here's how I did it: I added these lines to my /etc/crontab:

# minute, hour, day of the month, month, and weekday
# 0-59,   0-23, 1-31,             1-12,  0-7 (0 & 7 = Sunday)
  23      0     3                 *      *   root cd /var/named/etc && wget -N ftp://ftp.internic.net/domain/named.root

The first two lines are comments, but they help me set up the timing correctly for entries. As you can see, the third line is triggered at the 23rd minute of the 0th hour (0:23) on the third day of every month. If you think monthly is too often, give it a comma delimited list, e.g. 3,6,9,12 for quarterly.

The next column indicates the user to run as. This column is unique to /etc/crontab; don't put it into other crontab files.

The last column is the command that is executed. I run named in a chrooted jail. The first thing, then, is to cd into the jail's /etc directory. If and only if that is successful, we get the file. The -N switch tells wget to test whether the file is newer than our copy, and only fetch it if it is newer.

That's it.

There are other files one could grab from time to time. OpenAFS users may want to grab the list of public AFS servers and snoop around in, say, NASA's AFS servers. Like so:

0  0    * *  0 root cd /etc/openafs/ && wget -N http://grand.central.org/dl/cellservdb/CellServDB

I will leave as an exercise for the student when and how often that runs.