Different channel generation

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1

Hi!

I installed NixOS 21.11 (minimal ISO) in a VM and used NixOps inside latest docker nixos/nix image to deploy a new configuration/generation without specifying a particular channel anywhere.
The output of nix-channel --list is:
nixos nixos-21.11 release nixos-21.11.337975.eabc3821918
Somehow in the GRUB boot menu the generations 1-4 alternate between 21.11 and 22.05pre, and I’m wondering why?

edit:
Turns out the docker image is on 22.05pre:
bash-4.4# nix-channel --list
nixpkgs nixpkgs-unstable release nixpkgs-24.05pre583512.01737456dfe4

Kind regards,
Paul

2

This is the tag for nixos-unstable. Likely the nixops operations are running under unstable.

3

Yes, I figured that had to be it indeed.

Related question:

The manual states:

If you wish to change the channel used by the system-level configuration ( /etc/nixos/configuration.nix ), ensure you run the correct nix-channel command as root:

Is it not possible to declare the channel in configuration.nix explicitly?

4

With flakes, absolutely.

pre-flakes. The convention was NIX_PATH=nixpkgs=/path/to/nixpkgs. If you do echo $NIX_PATH, it should point to file paths, that’s where nixpkgs is coming from. nix-channel command just happened to update those paths, which gives the sense of “updating”.

But I haven’t used nixops too much, so i can’t comment on that workflow.

5

Thanks for your quick responses!

Is the flake interface stable yet? I’m relatively new to Nix, does it make sense to learn using flakes instead of derrivations?

6

Flakes are pretty good.

Nixops is a cool tool, but all development is going into nixops 2.

Quick Plug for

Which is a flake only deployment tool which is actively being worked on.

Use the source Luke…
May the flakes be with you, always!