nixpkgs/nixos/modules/system/boot/timesyncd.nix
stuebinm 6afb255d97 nixos: remove all uses of lib.mdDoc
these changes were generated with nixq 0.0.2, by running

  nixq ">> lib.mdDoc[remove] Argument[keep]" --batchmode nixos/**.nix
  nixq ">> mdDoc[remove] Argument[keep]" --batchmode nixos/**.nix
  nixq ">> Inherit >> mdDoc[remove]" --batchmode nixos/**.nix

two mentions of the mdDoc function remain in nixos/, both of which
are inside of comments.

Since lib.mdDoc is already defined as just id, this commit is a no-op as
far as Nix (and the built manual) is concerned.
2024-04-13 10:07:35 -07:00

95 lines
3.8 KiB
Nix

{ config, lib, ... }:
with lib;
{
options = {
services.timesyncd = {
enable = mkOption {
default = !config.boot.isContainer;
defaultText = literalExpression "!config.boot.isContainer";
type = types.bool;
description = ''
Enables the systemd NTP client daemon.
'';
};
servers = mkOption {
default = config.networking.timeServers;
defaultText = literalExpression "config.networking.timeServers";
type = types.listOf types.str;
description = ''
The set of NTP servers from which to synchronise.
Note if this is set to an empty list, the defaults systemd itself is
compiled with ({0..4}.nixos.pool.ntp.org) apply,
In case you want to disable timesyncd altogether, use the `enable` option.
'';
};
extraConfig = mkOption {
default = "";
type = types.lines;
example = ''
PollIntervalMaxSec=180
'';
description = ''
Extra config options for systemd-timesyncd. See
[
timesyncd.conf(5)](https://www.freedesktop.org/software/systemd/man/timesyncd.conf.html) for available options.
'';
};
};
};
config = mkIf config.services.timesyncd.enable {
systemd.additionalUpstreamSystemUnits = [ "systemd-timesyncd.service" ];
systemd.services.systemd-timesyncd = {
wantedBy = [ "sysinit.target" ];
aliases = [ "dbus-org.freedesktop.timesync1.service" ];
restartTriggers = [ config.environment.etc."systemd/timesyncd.conf".source ];
# systemd-timesyncd disables DNSSEC validation in the nss-resolve module by setting SYSTEMD_NSS_RESOLVE_VALIDATE to 0 in the unit file.
# This is required in order to solve the chicken-and-egg problem when DNSSEC validation needs the correct time to work, but to set the
# correct time, we need to connect to an NTP server, which usually requires resolving its hostname.
# In order for nss-resolve to be able to read this environment variable we patch systemd-timesyncd to disable NSCD and use NSS modules directly.
# This means that systemd-timesyncd needs to have NSS modules path in LD_LIBRARY_PATH. When systemd-resolved is disabled we still need to set
# NSS module path so that systemd-timesyncd keeps using other NSS modules that are configured in the system.
environment.LD_LIBRARY_PATH = config.system.nssModules.path;
preStart = (
# Ensure that we have some stored time to prevent
# systemd-timesyncd to resort back to the fallback time. If
# the file doesn't exist we assume that our current system
# clock is good enough to provide an initial value.
''
if ! [ -f /var/lib/systemd/timesync/clock ]; then
test -d /var/lib/systemd/timesync || mkdir -p /var/lib/systemd/timesync
touch /var/lib/systemd/timesync/clock
fi
'' +
# workaround an issue of systemd-timesyncd not starting due to upstream systemd reverting their dynamic users changes
# - https://github.com/NixOS/nixpkgs/pull/61321#issuecomment-492423742
# - https://github.com/systemd/systemd/issues/12131
(lib.optionalString (versionOlder config.system.stateVersion "19.09") ''
if [ -L /var/lib/systemd/timesync ]; then
rm /var/lib/systemd/timesync
mv /var/lib/private/systemd/timesync /var/lib/systemd/timesync
fi
'')
);
};
environment.etc."systemd/timesyncd.conf".text = ''
[Time]
NTP=${concatStringsSep " " config.services.timesyncd.servers}
${config.services.timesyncd.extraConfig}
'';
users.users.systemd-timesync = {
uid = config.ids.uids.systemd-timesync;
group = "systemd-timesync";
};
users.groups.systemd-timesync.gid = config.ids.gids.systemd-timesync;
};
}