[solved] Stupid noob mistake, rebuilt system and deleted my user account

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Edit: Nevermind, solved. I was able to ssh in from a different computer, login with the new account, zfs-rollback /persist/etc/nixos/configuration.nix, and recreate the deleted user account. Crisis averted, wew :blush:

Hello, I just did a nixos-rebuild switch and deleted my user account from /etc/passwd. I’m still logged in, still have my home directory, but can’t rollback to the previous generation since my logged-in account is no longer in the passwd database (no sudo). Is there any way to undo this?

TLDR: In configuration.nix users section, I added the name= property, thinking it was just metadata similar to the description= property, not realizing it was the actual account id.

The configuration.nix change I made that caused this:

Original:

  users = {
    mutableUsers = false;
    defaultUserShell = "/var/run/current-system/sw/bin/zsh";
    users = {
      root = {
        # disable root login here, and also when installing nix by running `nixos-install --no-root-passwd`
        # https://discourse.nixos.org/t/how-to-disable-root-user-account-in-configuration-nix/13235/3
        hashedPassword = "!";  # disable root logins, nothing hashes to !
      };
      bgibson = {
      	isNormalUser = true;
      	description = "My Account";
        passwordFile = "/persist/etc/users/bgibson";
        extraGroups = [ "wheel" "networkmanager" ];
        #openssh.authorizedKeys.keys = [ "${AUTHORIZED_SSH_KEY}" ];
      };
    };
  };

New broken:

  users = {
    mutableUsers = false;
    defaultUserShell = "/var/run/current-system/sw/bin/zsh";
    users = {
      root = {
        # disable root login here, and also when installing nix by running `nixos-install --no-root-passwd`
        # https://discourse.nixos.org/t/how-to-disable-root-user-account-in-configuration-nix/13235/3
        hashedPassword = "!";  # disable root logins, nothing hashes to !
      };
      bgibson = {
      	isNormalUser = true;
        name = "Byron Gibson"
      	description = "My Account";
        passwordFile = "/persist/etc/users/bgibson";
        extraGroups = [ "wheel" "networkmanager" ];
        #openssh.authorizedKeys.keys = [ "${AUTHORIZED_SSH_KEY}" ];
      };
    };
  };

That deleted my account bgibson (uid=1001) and created a new one Byron Gibson (uid=1003). Is there any way to revert this while I’m still logged in?

I’m running root on tmpfs, and everything else on ZFS, so this should be undo-able. However, without sudo I can’t do a zfs rollback to a prior snapshot of /etc/nixos/configuration.nix.

It occurs to me I can su into the new user account and use that account’s sudo ability to recreate my original account. But how do you su into an account with a space in the name? Edit: doesn’t look like su works without my logged in userid existing in /etc/passwd.

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