Host Keys and SSHing to EC2

I do a lot of work on EC2, where I ssh into a few instances I use for specific purposes. Each time I did this I'd get a prompt like:

$ ssh_ec2nf
The authenticity of host 'ec2-54-224-39-217.compute-1.amazonaws.com
(54.224.39.217)' can't be established.
ED25519 key fingerprint is SHA256:...
This host key is known by the following other names/addresses:
    ~/.ssh/known_hosts:591: ec2-18-208-226-191.compute-1.amazonaws.com
    ~/.ssh/known_hosts:594: ec2-54-162-24-54.compute-1.amazonaws.com
    ~/.ssh/known_hosts:595: ec2-54-92-171-153.compute-1.amazonaws.com
    ~/.ssh/known_hosts:596: ec2-3-88-72-156.compute-1.amazonaws.com
    ~/.ssh/known_hosts:598: ec2-3-82-12-101.compute-1.amazonaws.com
    ~/.ssh/known_hosts:600: ec2-3-94-81-150.compute-1.amazonaws.com
    ~/.ssh/known_hosts:601: ec2-18-234-179-96.compute-1.amazonaws.com
    ~/.ssh/known_hosts:602: ec2-18-232-154-156.compute-1.amazonaws.com
    (185 additional names omitted)
Are you sure you want to continue connecting (yes/no/[fingerprint])?

The issue is that each time I start my instance it gets a new hostname (which is just derived from the IP) and so SSH's trust on first use doesn't work properly.

Checking that "185 additional names omitted" is about the number I'd expect to see is ok, but not great. And it delays login.

I figured out how to fix this today:

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Risers for Foot Percussion

The ideal seat height for foot percussion is significantly higher than a typical chair. I've tried a few things over the years:
  • Stacking chairs: works great, until you come to a venue without any stackable chairs.

  • Drum stool: good (unless you buy a very cheap wobbly one like I did) but heavy and not good for flying with.

  • Adjustable booster: ok, though unavoidably bulky and the one I made is also too heavy for flying.

At Hashdance Weekend Kelsey had a set of furniture risers she let me borrow, and I liked them a lot! I decided to get a pair.

They do slide around a bit, though, because they're hard plastic on the bottom:

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Electric Lunchbox

People are often a lot more interested in hot meals, and my kids are no exception. I've tried a bunch of options here including putting rocks in thermoses (turns out kindergarteners worry more than you might think about whether they'll accidentally eat rocks that are bigger than their mouths), bringing a microwave and toaster (good, but too bulky for school especially when you count the battery), and ramen (great, but Lily only likes one kind and I'm worried she'll get sick of it). We recently got an electric lunchbox (this one because it was on sale, but there are a bunch) and it's pretty great!

It's insulated, and we prepare it the night before and put it in the fridge:

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Quarter Inch Cables are Devious

The quarter inch jack ("phone connector") is probably the oldest connector still in use today, and it's picked up a very wide range of applications. Which also means it's a huge mess in a live sound context, where a 1/4" jack could be any of:
  • Unbalanced or balanced line level (~1V). Ex: a mixer to a powered speaker.

  • Unbalanced instrument level (~200mV), high impedance. Ex: electric guitar.

  • Unbalanced piezo level (~50mV), high impedance. Ex: contact pickup on a fiddle.

  • Unbalanced speaker level (~30V). Ex: powered amplifier to passive speaker.

  • Stereo line level (2x ~1V). Ex: output of keyboard.

  • Stereo headphone level (2x ~3v). Ex: headphone jack.

  • Send and return line level (~2x 1V). Ex: input to and output from an external compressor.

  • Switch (non-audio). Ex: damper pedal on a keyboard, which would be normally open or normally closed.

  • 1V per octave (~5V). Ex: older modular synth.

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Cheesecake Frosting

To most Americans, "cream cheese" is savory. You put it on bagels, perhaps with egg, capers, or cured fish. You don't put it on dessert, right?

Except "cream cheese frosting" is a (delicious!) thing, most traditionally for carrot and red velvet cake. I think this incongruity is holding cream cheese frosting back, and it needs better branding. Specifically, I think we should call it "cheesecake frosting". It's essentially no-bake cheesecake already, and it's reasonably close in flavor and texture since they're both mostly cream cheese with sugar and fat.

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Attending LessOnline

The internet has massively decreased the cost and effort of publishing. While "random people writing on the internet" doesn't sound like a good source of information, this would fit the majority of my favorite writers. Except most aren't "random people" anymore: by writing publicly over time readers have learned what these authors are good at and when to pay attention; the writers have built reputations. And with extensive practice at getting ideas across and quick feedback from the world on how successful they were, many bloggers have progressed from people who really like writing to people who write very effectively.

The team behind LessWrong is organizing LessOnline, a "celebration of blogging, truthseeking, and original seeing", the weekend of May 30th in Berkley. Many of my favorite writers will be there, including Kelsey Piper (formerly the Unit of Caring, now a journalist), Scott Alexander (formerly Slate Star Codex, now Astral Codex Ten), Patrick McKenzie (Bits About Money), Zvi Mowshowitz (Don't Worry About The Vase), and Julia Wise (Otherwise). [1]

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