[Nix-dev] Troubleshooting boot failures & rollbacks

[stewart mackenzie]

Hi,

try using `$ nixos-rebuild boot` to test out your system first.

$ man nixos-rebuild

...
       boot
           Build the new configuration and make it the boot default
(as with nixos-rebuild switch),
           but do not activate it. That is, the system continues to
run the previous configuration
           until the next reboot.

       test
           Build and activate the new configuration, but do not add it
to the GRUB boot menu. Thus, if
           you reboot the system (or if it crashes), you will
automatically revert to the default
           configuration (i.e. the configuration resulting from the
last call to nixos-rebuild switch
           or nixos-rebuild boot).
...

kr/sjm