Previously, if the currently installed Nix is too old to evaluate
Nixpkgs, then nixos-rebuild would fail and the user had to upgrade Nix
manually. Now, as a fallback, we run ‘nix-store -r’ to obtain a binary
Nix directly from the binary cache.
This allows doing any necessary actions that were not in the installed
nixos-rebuild (such as downloading a new version of Nix). This does
require us to be careful that nixos-rebuild is backwards-compatible
(i.e. can run in any old installation).
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
We don't want to hardcode configuration options that the current kernel chose
for us when mounting the filesystem, since the defaults can change in the
future.
IIUC, <nixos> is going to be deprecated someday in the future, and as
most of those references are already replaced I guess it's safe to
replace it here as well, as it is only relevant on new/updated
installations.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
It's already set in hardware-configuration.nix so this just confuses
people.
Also get rid of boot.initrd.kernelModules, since
hardware-configuration.nix is supposed to figure that out as well.
Commit 31203732b3 dropped the reference to
<nixos> from NIX_PATH (nixos/modules/programs/environment.nix) and thus
prevents systems that are not using channels from rebuilding.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
So, we get the old behaviour of nixos-hardware-scane if we run the
following command:
nixos-generate-config --no-filesystems --show-hardware-config
This allows to use scripts in order to fetch NixOS specific hardware
information, without the need to duplicate code elsewhere.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
The attributes swapDevices and imports add a space character after the
eqals sign, which is unnecessary. I know, I'm a pedantic douche bag but
it hurts my eyes.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
This is to get back the old behavior of nixos-hardware-scan, which
didn't include fileSystems and swapDevices.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
If this option is given, nixos-generate-config will write the
configuration to /etc/nixos under the given root, and only emit
fileSystems attributes for filesystems under the given root directory.
The typically use case is at installation time, where you can say:
$ nixos-generate-config --root /mnt
which will create /mnt/etc/nixos/{configuration.nix,hardware-configuration.nix}.
Also add a --force flag to force overwriting configuration.nix.
Having configuration.nix generation hidden underneath nixos-option
never made sense, also given that there was another command to
generate part of the configuration (nixos-hardware-scan). Now
nixos-generate-config produces both configuration.nix and
hardware-configuration.nix. The latter is overwritten while the
former is not.
