Chrony

`services.chrony.autotrimThreshold`

Maximum estimated error threshold for the rtcautotrim command. When reached, the RTC will be trimmed. Only used when is enabled.

Type: positive integer, meaning >0

Default

30

Example

10

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.directory`

Directory where chrony state is stored. Type: string

Default

"/var/lib/chrony"

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.enable`

Whether to synchronise your machine's time using chrony. Make sure you disable NTP if you enable this service.

Type: boolean

Default

false

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.enableMemoryLocking`

Whether to add the -m flag to lock memory.

Type: boolean

Default

"config.environment.memoryAllocator.provider != \"graphene-hardened\""

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.enableNTS`

Whether to enable Network Time Security authentication. Make sure it is supported by your selected NTP server(s).

Type: boolean

Default

false

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.enableRTCTrimming`

Enable tracking of the RTC offset to the system clock and automatic trimming. See also

::: {.note} This is not compatible with the rtcsync directive, which naively syncs the RTC time every 11 minutes.

Tracking the RTC drift will allow more precise timekeeping, especially on intermittently running devices, where the RTC is very relevant. :::

Type: boolean

Default

true

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.extraConfig`

Extra configuration directives that should be added to chrony.conf

Type: strings concatenated with "\n"

Default

""

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.extraFlags`

Extra flags passed to the chronyd command. Type: list of string

Default

[ ]

Example

["-s"]

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.initstepslew.enabled`

Allow chronyd to make a rapid measurement of the system clock error at boot time, and to correct the system clock by stepping before normal operation begins.

Type: boolean

Default

true

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.initstepslew.threshold`

The threshold of system clock error (in seconds) above which the clock will be stepped. If the correction required is less than the threshold, a slew is used instead.

Type: floating point number or signed integer

Default

1000

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.package`

The chrony package to use. Type: package

Default

pkgs.chrony

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.serverOption`

Set option for server directives.

Use "iburst" to rapidly poll on startup. Recommended if your machine is consistently online.

Use "offline" to prevent polling on startup. Recommended if your machine boots offline or is otherwise frequently offline.

Type: one of "iburst", "offline"

Default

"iburst"

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix

`services.chrony.servers`

The set of NTP servers from which to synchronise.

Type: list of string

Default

config.networking.timeServers

Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/services/networking/ntp/chrony.nix