nixpkgs/nixos/modules/services/networking/ntpd.nix

91 lines
1.7 KiB
Nix

{ config, pkgs, ... }:
with pkgs.lib;
let
inherit (pkgs) ntp;
stateDir = "/var/lib/ntp";
ntpUser = "ntp";
configFile = pkgs.writeText "ntp.conf" ''
# Keep the drift file in ${stateDir}/ntp.drift. However, since we
# chroot to ${stateDir}, we have to specify it as /ntp.drift.
driftfile /ntp.drift
${toString (map (server: "server " + server + " iburst\n") config.services.ntp.servers)}
'';
ntpFlags = "-c ${configFile} -u ${ntpUser}:nogroup -i ${stateDir}";
in
{
###### interface
options = {
services.ntp = {
enable = mkOption {
default = true;
description = ''
Whether to synchronise your machine's time using the NTP
protocol.
'';
};
servers = mkOption {
default = [
"0.pool.ntp.org"
"1.pool.ntp.org"
"2.pool.ntp.org"
];
description = ''
The set of NTP servers from which to synchronise.
'';
};
};
};
###### implementation
config = mkIf config.services.ntp.enable {
# Make tools such as ntpq available in the system path
environment.systemPackages = [ pkgs.ntp ];
users.extraUsers = singleton
{ name = ntpUser;
uid = config.ids.uids.ntp;
description = "NTP daemon user";
home = stateDir;
};
jobs.ntpd =
{ description = "NTP Daemon";
wantedBy = [ "ip-up.target" ];
partOf = [ "ip-up.target" ];
path = [ ntp ];
preStart =
''
mkdir -m 0755 -p ${stateDir}
chown ${ntpUser} ${stateDir}
'';
exec = "ntpd -g -n ${ntpFlags}";
};
};
}