Blast Furance

We made a blast furnace, following David Gingery’s The Charcoal Foundry. Here are some pictures of the firing process. We haven’t melted or cast any metal yet.

Slow initial burn to drive out most of the water

Blast furnace in action to completely dry it

You can tell we’re trained professionals by the fan setup

Blast furnace meat is best meat

Richard looking dubiously at the furnace

DIY Hard drive carrying case

Today’s project was a hard drive carrying case. I wanted something to securely store hard drives. When I looked around on ebay and amazon, I saw some nice cases and some crappy plastic molded ones. Even the terrible ones were at least $50, so I made my own.

HDD Carrying Case Exerior

I bought a used ammo case at the rather excellent local army surplus store. Then I padded all sides. I had spare EVA foam “puzzle piece” style mats from a gym setup lying around. I cut out the pieces with scissors. That’s it.  I was expecting more steps, but nothing needed glued in place. I was planning on adding inserts for the empty slots, but it seems secure enough. If you’re making one, you could also glue the top onto the lid, so you don’t have to take it out manually.

HDD Case Interior

Getting the Adafruit Pro Trinket 3.3V to work in Arch Linux

I’m on Linux, and here’s what I did to get the Adafruit Pro Trinket (3.3V version) to work. I think most of this should work for other Adafruit boards as well. I’m on Arch Linux, but other distros will be similar, just find the right paths for everything. Your version of udev may vary on older distros especially.

  1. Install the Arduino IDE. If you want to install the adafruit version, be my guest. It should work out of the box, minus the udev rule below. I have multiple microprocessors I want to support, so this wasn’t an option for me.
  2. Copy the hardware profiles to your Arduino install. pacman -Ql arduino shows me that I should be installing to /usr/share/aduino.  You can find the files you need at their source (copy the entire folder) or the same thing is packaged inside of the IDE installs.
  3. Re-configure “ATtiny85” to work with avrdude. On arch, pacman -Ql arduino | grep "avrdude.conf says I should edit /usr/share/arduino/hardware/tools/avr/etc/avrdude.conf. Paste this revised “t85” section into avrdude.conf (credit to the author)
  4. Install a udev rule so you can program the Trinket Pro as yourself (and not as root).
  5. Add yourself as an arduino group user so you can program the device with usermod -G arduino -a <username>. Reload the udev rules and log in again to refresh the groups you’re in. Close and re-open the Arduino IDE if you have it open to refresh the hardware rules.
  6. You should be good to go! If you’re having trouble, start by making sure you can see the correct hardware, and that avrdude can recognize and program your device with simple test programs from the command link. The source links have some good specific suggestions.

Sources:
http://www.bacspc.com/2015/07/28/arch-linux-and-trinket/
http://andijcr.github.io/blog/2014/07/31/notes-on-trinket-on-ubuntu-14.04/

The life-changing magic of tidying up

Summary of “the life-changing magic of tidying up”:

Marie Kondo writes the “KonMari” method. The book ends up being as much about her mistakes in learning how to tidy as it is about how to tidy. The book conveys a certain positive energy that makes me want to recommend it, but the author also brings that energy in reaction to a kind of previous stress which accompanied tidying, which she does not seem to have completely dropped–if you are mysteriously anxious and feel you MUST discard everything after reading her book, this may be why.

The primary point she makes is meant to cure it: Decide what to keep and what to discard by physically touching each item, and asking if it brings you joy.

The rest of the method:

  • Positivity. Everything in your house loves and wants to help you. If it is time to send off some of the items on their next adventure, this is no reason to be sad or anxious. You had a great time meeting, and they and you were both happy.
  • Tidy all at once (at least by category, but preferably in a multi-day binge).
  • Physically gather the category in once place, touching everything and asking if it brings you joy.
  • Find out what you’ll keep and discard before putting things away or organizing.
  • Organizing: ??? [I didn’t get any big takeaways here].

Marie Kondo’s best advice is realizations from her past mistakes–the sort of methods which seems reasonable to try, but end up being wrong for subtle reasons. They are:

  • Tidy by category, not place. Otherwise, you won’t realize everything you have.
  • “Storage” is storing things neatly, and lets you have more and more things. This is different than tidying, which is about bringing things in harmony, and having only things you love. Becoming better at “storage” can make you unhappy.

She also has encountered her clients making mistakes. For each category of things (clothes, books, etc) there are many reasons clients may not want to throw something out. Most of the book is meant to illustrate why these things are useless, and why throwing them out is okay and will make you happier.

The fun part is that many clients were more confident and more in touch with what they valued and who they wanted once they had only possessions they loved.

Continue reading

DDoS

za3k.com was the site of a DDoS attack. I’m pretty sure this was because my wordpress installation was compromised, and the hacker who took control of my server was herself DDoSed.

More updates to come, but the short story is that I’ll be formalizing my install and eventually containerizing + hardening everything

Archiving all bash commands typed

This one’s a quickie. Just a second of my config to record all bash commands to a file (.bash_eternal_history) forever. The default bash HISTFILESIZE is 500. Setting it to a non-numeric value will make the history file grow forever (although not your actual history size, which is controlled by HISTSIZE).

I do this in addition:

Archiving all web traffic

Today I’m going to walk through a setup on how to archive all web (HTTP/S) traffic passing over your Linux desktop. The basic approach is going to be to install a proxy which records traffic. It will record the traffic to WARC files. You can’t proxy non-HTTP traffic (for example, chat or email) because we’re using an HTTP proxy approach.

The end result is pretty slow for reasons I’m not totally sure of yet. It’s possible warcproxy isn’t streaming results.

  1. Install the server
  2. Make a warcprox user to run the proxy as.
  3. Make a root certificate. You’re going to intercept HTTPS traffic by pretending to be the website, so if anyone gets ahold of this, they can fake being every website to you. Don’t give it out.
  4. Set up a directory where you’re going to store the WARC files. You’re saving all web traffic, so this will get pretty big.
  5. Set up a boot script for warcproxy. Here’s mine. I’m using supervisorctl rather than systemd.
  6. Set up any browers, etc to use localhost:18000 as your proxy. You could also do some kind of global firewall config. Chromium in particular was pretty irritating on Arch Linux. It doesn’t respect $http_proxy, so you have to pass it separate options. This is also a good point to make sure anything you don’t want recorded BYPASSES the proxy (for example, maybe large things like youtube, etc).

Mail filtering with Dovecot

This expands on my previous post about how to set up an email server.

We’re going to set up a few spam filters in Dovecot under Debian. We’re going to use Sieve, which lets the user set up whichever filters they want. However, we’re going to run a couple pre-baked spam filters regardless of what the user sets up. Continue reading