Why unlock using flash drive: Because you don’t have keyboard or monitor connected to your RPi, do you? Information: I was using Pezz’s gist, which helped me a lot. Thank you very much, Pezz. Why Arch linux: because I wanted to try Arch, default kernels of Raspbian and Pidora lack(lacked? Maybe already have) needed encryption modules. SD card preparation Download Arch linux image from here: RPi downloads
On your desktop check list of devices:
$ ls -lah /dev | grep sd brw-rw---T 1 root disk 8, 0 Aug 11 15:43 sda brw-rw---T 1 root disk 8, 1 Aug 11 15:43 sda1 brw-rw---T 1 root disk 8, 2 Aug 11 15:43 sda2 brw-rw---T 1 root disk 8, 3 Aug 11 15:43 sda3 brw-rw---T 1 root disk 8, 4 Aug 11 15:43 sda4 Now insert SD card into card reader on desktop, and check list once again. You’ll see a new device we’ll write Arch linux image to.
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