NTP Client

Each gokrazy instance comes with a built-in NTP client (see Instance Config → GokrazyPackages for more details on system packages) which sets the system clock once the network is up.

NTP servers

The NTP client determines which servers to query in the following order:

  1. Servers specified on the command line, if any
  2. NTP servers provided by the network’s DHCP server, if any
  3. The default *.gokrazy.pool.ntp.org server pool

If your DHCP server is configured to provide NTP servers (DHCP option 42), they are used automatically — no configuration required. If they cannot be reached, the default pool is used temporarily.

To use your own NTP servers instead, specify them as positional command-line flags:

{
    "Hostname": "dynamic",
    "Packages": [
        "github.com/gokrazy/fbstatus",
        "github.com/gokrazy/hello",
        "github.com/gokrazy/serial-busybox",
        "github.com/gokrazy/breakglass",
    ],
    "PackageConfig": {
        "github.com/gokrazy/gokrazy/cmd/ntp": {
            "CommandLineFlags": [
                "ntp.example.org",
                "192.168.178.1"
            ]
        }
    }
}

Real-time clock

If your device has a real-time clock (RTC), the NTP client keeps it updated, so that the correct time is available directly after a reboot. Devices without an RTC start with an approximately correct clock restored from the last shutdown until the network is up. This requires a writable perm partition, where the time of the last shutdown is stored.