nichts/docs/dualboot.md

Dualbooting NixOS and FreeBSD

Out of curiosity, I decided to dual-boot NixOS and FreeBSD on my laptop, sharing one disk. I document the process here for future reference:

Linux install

First, flash a stick with NixOS, then boot into it, wipe your disk, create two partitions, one being boot, the other your main NixOS partition. Then, follow these commands:

sudo su

cryptsetup luksFormat /dev/diskname/partition

cryptsetup open /dev/diskname/partition crypt

mkfs.btrfs -L nixos /dev/mapper/crypt

mount /dev/mapper/crypt /mnt

btrfs create subvolume /mnt/nix
btrfs create subvolume /mnt/home
btrfs create subvolume /mnt/persist

mkdir /mnt/boot
mount /dev/partition # boot partition

Then, copy my nixos flake to /mnt, you can remove it from there later on.

git clone https://github.com/bloxx12/nichts /mnt

In there, change the file system uuids to the correct ones, you can see them using

sudo blkid

Then, install NixOS itself:

nixos-install --impure --flake /mnt/nichts#<hostname> -j 1 --cores 2

Wait for that to finish, then reboot.

If your system works, great! if not, redo from the beginning.

After that, set up FreeBSD the following way: