NixOS-based rescue image, intended for a USB stick.
Should be able to download an image from releases, or clone and build locally.
Has a convenience target that will run the image in a VM to ensure it has the
tools you're used to: nix run.
Has ZFS and BTRFS tools. Tries to start an SSH server automatically.
Please note that by default this permits root access to my ssh
key (see
users.users.root.openssh.authorizedKeys.keyFiles in configuration.nix) and
uses root:rescue as the login credentials, so you may want to change those
settings.
The configuration is split into the general settings (packages, users, etc.) in
configuration.nix, which can be separately importable as
rescue.nixosModules.default, and hardware-configuration.nix (I should
probably choose a different name) which has the settings for putting it ont a
bootable drive.
The advantage here is that the module settings can be imported as a separate
boot target on a machine, which I was inspired to attempt by this
config.
For example, on one of my machines, I import this module, minimally modified
from that link, which gives me a NixOS Rescue boot target, complete with all
my settings configured in this flake. Once I've added this flake as an input, I
can just import this module in a config and have a machine automatically
provide a separate boot target. NB: if copying this, you'll likely want to
remove the @boot/ subvolume I added below.
{
pkgs,
rescue,
...
}: let
netboot = import (pkgs.path + "/nixos/lib/eval-config.nix") {
inherit (pkgs) system;
modules = [
(pkgs.path + "/nixos/modules/installer/netboot/netboot-minimal.nix")
rescue.nixosModules.default
];
};
in {
boot.loader.grub.extraEntries = ''
menuentry "NixOS Rescue" {
linux ($drive1)/@boot/rescue-kernel init=${netboot.config.system.build.toplevel}/init ${toString netboot.config.boot.kernelParams}
initrd ($drive1)/@boot/rescue-initrd
}
'';
boot.loader.grub.extraFiles = {
"rescue-kernel" = "${netboot.config.system.build.kernel}/bzImage";
"rescue-initrd" = "${netboot.config.system.build.netbootRamdisk}/initrd";
};
}