I installed NixOS 18.03 from Ubuntu on another partition following the NixOS manual's "2.4. Installing from another Linux distribution" section. Everything went fine, but I did a couple idiotic things [?], namely:
Forgot to add the extra GRUB boot loader entry for the Ubuntu installation before
nixos-install. Added it as an afterthought after install, and did a reboot (of course, no Ubuntu entry)
Did not enable any networking in
configuration.nix, and ended up with no network configuration commands after reboot to connect to wifi. The catch 22 is that
nixos-rebuild switchrequires a network connection, so I couldn't finalize any changes.
So my thinking was that I can boot from a NixOS Live CD (17.03),connect to our wifi and somehow rebuild the config of the installation.
It is more than possible that I am missing something essential, have incorrect assumptions above etc; fairly new at nix and NixOS.
EDIT: I forgot to include how my partitions are set up and what I tried before successfully installing NixOS.
Partitions (mountpoints from Ubuntu):
sda ├─sda1 ntfs Recovery # some Win7 artifact ├─sda2 vfat /boot/efi ├─sda3 vfat NIXBOOT # boot partition (esp, boot) ├─sda4 ext4 onyx # NixOS data ├─sda5 swap # Ubuntu swap │ └─cryptswap1 swap [SWAP] ├─sda6 ext4 # (Arch install) ├─sda7 ext4 / # Ubuntu install ├─sda8 swap nixswap └─sda9 ext4 home
I didn't want to mess up the Ubuntu boot partition, so I created another one (
/dev/sda3). My plan was to later include a menu entry in Ubuntu's GRUB for NixOS, but for now, install, reboot and test booting NixOS from GRUB console (
sudo PATH="$PATH" NIX_PATH="$NIX_PATH" `which nixos-install` --root /mnt --no-bootloader
After reboot, I couldn't see anything on the NixOS boot partition. Went back to Ubunut, installed without
--no-bootloader, remembered to add an entry for Ubuntu and reboot. (It was only after this that I realized that
systemd-boot and GRUB are two completely different things...)
UPDATE: I was able to get back to Ubuntu by selecting the Ubuntu boot partition as an alternative boot device in BIOS, and the usual GRUB menu came up. I may just redo the install with the right config.