nix run nixpkgs.nix-info don't work in generated ISO

[davidak]

[root@targets-host:~]# nix run nixpkgs.nix-info -c nix-info -m
warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels/nixos' does not exist, ignoring
warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels' does not exist, ignoring
error: file 'nixpkgs' was not found in the Nix search path (add it using $NIX_PATH or -I)

[root@targets-host:~]# nix-channel --list
nixos https://nixos.org/channels/nixos-19.03

[zimbatm]

It looks like there are multiple issues with nix-info:

It fails when the channel hasn't been populated. nix-channel --update work around that issue.

It doesn't report the nixpkgs version that was used to build the current system. Which is what we are interested in for nixos bug reports.

[davidak]

I tried with the official installer iso. It works there.

Maybe nix-info should be installed on any NixOS installation or even be included in Nix with nix info? Whould that solve this issue and also when the system has no internet connection?

[zimbatm]

Actually I misread your logs. The issue here is that nix run is not able to find the channel and evaluate nixpkgs in the first place. That's fine, not all systems should come with a channel pre-loaded as it's quite large.

[davidak]

That's fine, not all systems should come with a channel pre-loaded as it's quite large.

That makes sense. But it should still be possible to create useful bugreports, so nix-info should work, even in such cases.

I'll create an issue upstream since this is not a nixos-generators problem.