It was time to renew several certificates, and I noticed that Lets Encrypt’ new certbot (as of 0.10 or 0.11) was issuing single certificates for zones grouped together, with the Alt Name set for the other DNS entries for zones sharing a single IP.

What does this mean in English? Think of an SNI SSL setup “virtual host” working like a party line (if you’re old enough to remember what those are). Everyone gets a different “ring”, and picks up when appropriate. Well, since they’re all on the same line, Lets Encrypt (LE) now sticks them all on the same certificate.

While this likely cleans a few things up on their end- having possibly only one certificate for the entire set of hosts- you may not always want that. In fact it’s quite unlikely that you do.

For instance: I run several personal, business, and other’s domains on this colocated machine. Several are “vanity” domains, and have no place being seen when someone clicks “View Certificate” on a business site. “saab.party” is cute (at least I think so), but doesn’t need to be there, just because it’s on the same machine.

A counterargument might be “Don’t use LE for business”, but for smaller businesses- it makes sense if you are using it only for web security, and not for purchasing or selling items. Many smaller business are also configured as VirtualHosts, rather than having their own machine, or even their own IP. It just isn’t part of their actual business- which can be hard to remember for those of us who live vicariously through the internet.

For now, I’m going to group my LE update and new requests separately for (www.?)domain.tld groups, the way it used to work.

I figure I might as well follow up on yesterdays’ post:

• Writing Tech 2 binaries onto a PCMCIA card is as simple as ‘dd’.

All you need to do is load Linux on a machine with a supported PCMCIA cardbus interface, load drivers, and write the image to the drive’s /dev/ entry using ‘dd’.

I used conv=dsync just to be safe- but it worked perfectly, which is more than I can say than how I would feel about shelling out hundreds of dollars to do the same under Windows.

I was able to get data from the Impala (4th digit of VIN is production series, or, ‘W’ in this case), and found that the front passenger speed sensor is not reporting. Time to check the harness and sensor!

The local pub has a $2 Taco Tuesday special- Tacos are $2, and Burgers are $2 off. It’s become a bit of a weakly followed tradition in our household. As usual, they were delicious, even a bit overloaded. I certainly wouldn’t have ordered two if I had known.

I’ve got the battery installed in the Impala, which is running perfectly- but it is still throwing an ABS light. I have owned a Tech 2 for use with my SAABs, and I have a secondary GM card which is semi-generic for all GMs through 2010ish- which I had never used.

I tried to use it today, and no go- it’s not formatted properly. The Tech 2 hangs solid after downloading it, so that just doesn’t do.

The GM image is a single binary blob, and the Tech 2 only works with linear memory, so I’m going to boot from a Puppy/DSL USB drive and DD the image directly to the flash device.

It’s about 20 degrees out and dark, so I won’t be testing anything until tomorrow.

As someone who has been in charge of not only managing equipment, but specifications, and design- it’s just good sense to not always go for the cheapest product. Sometimes it works well, and sometimes it doesn’t even make it to the point of depreciation to make it a worthwhile venture. This is pretty well known- the axiom “measure twice, cut once” by doing appropriate research before purchase works quite well, but when it comes time to replace that hardware- how many times have you considered a new purpose for a device after replacement? It may still have a function to fill.

This picture above is a small project I’ve been meaning to undertake – adding a portable Ethernet/wireless repeater for use downstairs. This router was replaced recently with a smaller, feature rich unit by GL.iNet, so other than keeping it as a backup, I didn’t really have much use for it.. or did I?

It was running Advanced Tomato firmware, which worked great, but just wasn’t what I needed as it’s repeating capabilities just aren’t quite there- it’ll bridge, and it’s a decent AP, but that’s where it ends.

Having read of people bricking units, I decided to open it ahead of time, connecting a JTAG (USB to Serial) adapter so I had console access should things go wrong.

I had the unit erase the NVRAM, resetting to defaults, then rebooted, stopped it before chaining to the OS, started it as a TFTP server, and uploaded the latest DD-WRT firmware.

Now, I have nearly 100% signal strength downstairs, and a handy place to plug in wired devices if necessary. Total cost: about an hour of time, while still learning how to reuse equipment that can (barely) still be depreciated.

If you read the title, you may say “no kidding” to yourself, but sometimes we lose sight that there can be more than one way to approach a problem.

For instance, I have a car with a dead battery, and no matter how I tried to mend it with distilled water, trickle charging, discarge, etc- it just wasn’t coming back. I could trickle it up to 13v, but it was down to maybe 10v and ~85A the next day.

We all know that car batteries are expensive- most of them start at at least 3 digits ($100). I stopped by the well known auto shops nearby, and they were $120 to $160 with the core! I went searching for refurbished batteries, but nobody had Group 34 batteries available- it’s still winter and everyone else has a dead battery, too.

I stopped by Wal-Mart to get 4 quarts of Rotella 15-40W for $10 (great price), and saw that all of their Group 34 batteries were out (the cheapest of which was still $104.99), but they had Group 78.

Wal-Mart has a new “Value Power” brand made by Johnson Controls (They’re that company that makes the incredibly expensive “Optima” series). I checked the specifications on the “Value Power” 78- 600CCA, 750 above freezing. The Interstate battery I am looking to replace is 700CCA, and 800 above freezing, accordingly. Their duty cycles are nearly the same.

If you cross reference The BCI group sizes, we’ll find that they’re roughly the same dimensions- and more importantly, the posts are the same (positive is on the left when facing forward):

34 	10.30 6.80 7.90  L/H-POS
78 	10.30 7.10 7.30  L/H-POS

The dimensions, as we saw above are fairly compatible, and it even has the same little retainer “lip” for holding the battery in place.

I had already mentally measured the length of the cable under the hood when I pulled the battery (and how they mounted), which prompted me to then grab that $49.88 Group 78 battery with a pack of $2.79 “side mount charging post adapters”. The total cost? $57.27.

I was not only able to find what I needed, but I saved nearly half the expense by approaching my problem from a different direction by looking at the other resources I had available (car runs perfectly, by the way).