Move Nix Store to new partition
The tutorial will teach you how to relocate /nix
to a new
device on non NixOS Hosts. A summary of how this could be done on NixOS is at the bottom.
This has not been tested on NixOS but there may still be a way:
On *BSD/Linux Host
The device that /nix is on has no more space
$ du -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 182G 180G 2G 99% /
Stop nix daemon
$ sudo systemctl stop nix-daemon.service
Move backup /nix; mv /nix to /nix.bak
$ ls -alF /nix
total 1068
drwxr-xr-x 4 root root 4096 Jan 22 02:43 ./
drwxr-xr-x 26 root root 4096 Feb 8 12:17 ../
drwxrwxr-t 1555 root nixbld 1077248 Feb 8 12:05 store/
drwxr-xr-x 4 root root 4096 Jan 22 02:43 var/
$ cd /
$ tar -afp /nix.tgz /nix /nix.bak
$ sudo mv /nix /nix.bak # in case something goes horribly wrong
Mount new device. You will need to add this device to `/etc/fstab`
$ mount /nix
$ du -h
Filesystem Size Used Avail Use% Mounted on
/dev/sdb1 300G 0G 300G 0% /nix
Restore /nix from /nix.tgz; verify contents
$ cd /
$ sudo tar -xf /nix.tgz
$ nix-store --verify --check-contents
Start nix-daemon
$ sudo systemctl start nix-daemon.service
NixOS
Template:See also Add rescue-boot.nix to your imports section.
nixos-rebuild (and pray you have ~300mb free on /boot/)
run the installer from grub at any time.
adjust your configuration.nix so it expects /nix
to be at the new place, and nixos-rebuild boot, so it doesnt break after you move it
Now reboot and move it.