US nuclar missiles secrets leak via soldiers using memorizing apps.
A two-hour conversation about Malthus with @tylercowen.
Classic card magic with Ricky Jay.
Batavia's graveyard, the crazy story of the shipwrecked flagship of the Dutch East India Company.
Inside a Ghost Gown of Abandoned Disney Castles.
Fungi and how they set our body temperature.
If you love the absurd:
I spent the morning felling another four trees that were taken over by bark beetles. In order to prevent the larvae from developping into bugs and then spreading to neighbouring trees, one has to remove all the bark from the tree. This quite tedious but it helps to have a really sharp knife that is designed for that purpose.
The inside of a piece of bark with bark beetle larvae from a tree that I had just felled because of them. You can see the channel at the top where the parent bugs laid the eggs, from which the larvae then gnaw their channels perpendicularly, getting larger along the way.
I usually don't consider myself a "fan" of anything, but when it comes to the work of @MaxCRoser at Our World in Data, and @robertwiblin as an interviewer, the term applies quite well.
So imagine what a treat for my ears the podcast with them both has been! Lots of background on one of the best sites on the interwebs. If you know it only for its statistics about the CoVid19-pandemic, make sure to check out their other topics as well!
A while back, my installation of HomeAssistant broke down and that caused some minor inconveniences, like lamp switches no longer working. Nevertheless, I only this week looked into what happened and whether I could recover the setup. The pairing of the lamps and switches is not something that one wants to repeat unnecessarily.
The most likely cause turned out to be it: The microSD-card in the RaspberryPi4 broke. They are known to do that, unfortunately. So I bought a new one, pulled an image from the old card and after a bit of fiddling, I was able to restore a snapshot that I had taken not long ago. All good.
I bought an additional microSD out of concern for the same thing happening to the other RasPi, the one that runs this very website.
ssh berr "dd if=/dev/mmcblk0" > berry.img
losetup --find --show -P berry.img
I had not known about the option -P before and it is exactly what I needed in this case: additional device files for the partitions within the disk image, not just a loop device for the iamge itself. So I could go on and check the filesystems' integrity:
fsck.vfat /dev/loop25p1
e2fsck -f /dev/loop25p2
Not surprisingly, there were several errors to be fixed in the main partition. After all, I was pulling the image from a running system that was continuously writing logs and stuff to the disk.
Then I tried to write the image to the new microSD-card.
dd if=berry.img of=/dev/mmcblk0 bs=2048
But this did not work because the new card was slightly smaller than the old one. Apparently 32GB are not what they used to be. Annoying!
So I had to figure out the number of sectors that remained on the new card for the Ext4-filesystem.
cfdisk /dev/loop25
cfdisk /dev/mmcblk0 # compare numbers in cfdisk
resize2fs /dev/loop25p2 61083647s
losetup --detach /dev/loop25
dd if=berry.img of=/dev/mmcblk0 bs=2048
Take out the card and re-insert.
fsck.ext4 /dev/mmcblk0p2 # passes the test now!
cfdisk /dev/mmcblk0 # mark first partition as bootable
And that's it. I did not test whether the card actually boots up because it would cause unnecessary downtime. I am reasonably confident it will work, should the need arise.
I quite enjoyed this whole small exercise. It had been a while and one always learns something new in the process.
Song lyrics rarely stick with me, but this sentence from Ane Brun's Do you remember always has:
Do you remember when we forgot
How to smile at each other
To believe that the other
Wants only what's good for you
Genuine goodwill is probably an essential ingredient for lasting friendships and relationships. And it is not even that hard to muster once one is aware of it and decides that this is the right attitude to take.
Some long time ago, probably around 2005, I got convinced that I should use vi for quick edits in the terminal, instead of nano which I had been using for this purpose, for historical reasons.
So I added this simple line to my .bash_aliases:
alias nano='vim'
And to this day I type nano when I just quickly want to edit a file, just out of muscle memory, and I would be very surprised if I would end up in actual nano, not vim.
The latest video by Kurzgesagt is about the asteroid impact that killed the dinosaurs, and is brilliant as usual. This frame made me pause and ponder on a side-track:
Doesn't the Burj Khalifa tower look surprisingly large compared to mount everest? It isn't even a fair picture, because the mountain does not rise 8.8km out of the ocean, but "only" about 3.5km above the surrounding valleys.
Thus, climbing Burj Khalifa (which is a thing people do) just five times is the same height as climbing Everest from base camp. Disregarding the lack of oxygen at high altitudes and that the tower is much steeper.
Human-made structures start to approach the size of mountains, pointing up, not only down.
