Scripts to setup a Raspberry Pi OS image **before** flashing to SD card

Setup Raspberry Pi OS Image Script.md

Gist moved to real repository: https://github.com/cinderblock/RaspberryPi-Image-Generator

@cinderblock I just downloaded fresh copy of Raspbian Buster Lite, unpacked it and did this:

Here is my chroot:

user@laptop:~/download$ ll chroot/
total 76
drwxr-xr-x  2 root root 4096 Feb 13 10:56 bin/
drwxr-xr-x  3 root root 4096 May 19 10:55 boot/
drwxr-xr-x  4 root root 4096 Feb 13 10:51 dev/
drwxr-xr-x 79 root root 4096 Feb 13 11:09 etc/
drwxr-xr-x  3 root root 4096 Feb 13 10:55 home/
drwxr-xr-x 16 root root 4096 Feb 13 10:58 lib/
drwx------  2 root root 4096 Feb 13 11:09 lost+found/
drwxr-xr-x  2 root root 4096 Feb 13 10:51 media/
drwxr-xr-x  2 root root 4096 Feb 13 10:51 mnt/
drwxr-xr-x  3 root root 4096 Feb 13 10:55 opt/
drwxr-xr-x  2 root root 4096 Feb  8 21:47 proc/
drwx------  2 root root 4096 May 19 10:56 root/
drwxr-xr-x  4 root root 4096 Feb 13 10:51 run/
drwxr-xr-x  2 root root 4096 Feb 13 10:58 sbin/
drwxr-xr-x  2 root root 4096 Feb 13 10:51 srv/
drwxr-xr-x  2 root root 4096 Feb  8 21:47 sys/
drwxrwxrwt  2 root root 4096 Feb 13 11:09 tmp/
drwxr-xr-x 10 root root 4096 Feb 13 10:51 usr/
drwxr-xr-x 11 root root 4096 Feb 13 10:51 var/

Check to make sure bash inside chroot is indeed an ARM binary:

user@laptop:~/download$ file chroot/bin/bash 
chroot/bin/bash: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 3.2.0, BuildID[sha1]=3e5e2847bbc51da2ab313bc53d4bdcff0faf2462, stripped

Check if I am cheating and somehow have copied qemu-static-binary into the chroot:

user@laptop:~/download$ ll chroot/usr/bin/qemu-arm-static
ls: cannot access 'chroot/usr/bin/qemu-arm-static': No such file or directory

Finally, chroot:

user@laptop:~/download$ sudo chroot ./chroot/ /bin/bash
root@laptop:/#

Boom, we are in.

@dimitry-ishenko I think I might have run into problems trying this on a VPS so maybe it's the weird execution environment? I was getting a number of warnings from qemu about unimplemented calls. Trying again on a bare metal machine (x86-64 Intel i7-4770) seems to work without copying.

I guess it could also be just that that kernel is still slightly older (but 4.15.0-101-generic isn't that old). /etc/os-release says Ubuntu18.04 but I thought I was stuck on 17 at some point...

@cinderblock IIRC unimplemented calls are due to older qemu-{arm,aarch64}-* binaries and are mostly harmless. I used to get them on my 18.04 box as well. Google the exact error message, that's how I've found the explanation