[Nix-dev] smartd configuration change

[Peter Simons]

Nixos smartd users, please note that the configuration scheme has
changed in this commit:

  https://github.com/NixOS/nixos/commit/415ff3c39a6b39e571ddece06faef0cc84a5c86c

smartd used to expect a list of devices to monitor. After this patch, it
expects a list of attribute sets, which may have two attributes:

 - device: path to the device (required)
 - options: smartd options to apply to this particular device (optional)

A concrete example configuration would be:

  services.smartd = {
    enable = true;
    devices = [ { device = "/dev/sda"; } { device = "/dev/sdb"; options = "-d sat"; } ];
  };

Furthermore, the config option 'deviceOpts' can be used to configure options
that are applied to *every* device.

Take care,
Peter