Smartmontools

smartmontools is a package which provides tools for monitoring drives which support the S.M.A.R.T. system for monitoring hard drive health.

It includes the smartd and smartctl programs. smartd can be enabled on NixOS systems with the services.smartd module.

Example

/etc/nixos/configuration.nix

{
  services.smartd = {
    enable = true;
    devices = [
      {
        device = "/dev/sda"; # FIXME: Change this to your actual disk; use lsblk to find the appropriate value
      }
    ];
  };
}