Ntp Platform Service Editor Qnx view (platform-NtpPlatformServiceEditorQnx)

An example of an embedded Ntp Platform Service Editor for the JACE controller is shown below. This is the default view for the NtpPlatformServiceQnx.

Ntp Platform Service Editor Qnx settings

Figure 1. Ntp Platform Service Editor Qnx view


This view provides access to some of the key settings of the NTP daemon (ntpd) of the QNX OS running on the host controller platform.

There are two main areas: Settings at top and Time Servers at bottom.

This controller component settings in the Ntp Platform Service Editor Qnx include the following properties:
PropertyValueDescription
Enabledtrue or false (default)If true, the host will use NTP to sync its clock with time values retrieved from other servers.
NTP Host ModesServer (default)

Server (default): In addition to being an NTP client, this host will act as an NTP server. This configuration allows local network devices to use the host as a source of NTP data. Local network devices will also be able to query this host for additional NTP runtime information.

Server (Time Only): In addition to being an NTP client, this host will act as an NTP server. This configuration allows local network devices to use the host as a source of NTP data. Unlike "Server", local network devices will be unable to query this host for additional NTP runtime information.

Client: This host will act as an NTP client only. The NTP data retrieved by this host from configured servers will not be available to local network devices.

Sync Local Clock to NTPtrue (default)If true, the host will start the Network Time Protocol daemon. This boolean does not directly say that NTP will be used as a time source on this platform, rather, it enables that option. Additional properties below will inform the NTP daemon how time information now available will be used.
Sync Time At Bootfalse (default)If true, when the JACE boots, before the stations starts or the ntpd starts, it executes the ntpdate command. This updates the system local time.
Use Local Clock as Backupfalse (default)If true, should the specified NTP server(s) become unavailable at the time of a poll, the time used is provided by the system clock. This prevents the timing of the polling algorithm in the ntpd (which is executed at specified/changing intervals) from being reset. A true value does not result in any change to the NTP daemon’s polling interval (frequency). In fact, by using the local system clock the NTP-calculated polling time would remain the same, and thus not result in more polling.
Generate NTP Statisticsfalse (default)If true, the NtpPlatformService reports whatever information it can about its operation. To access these statistics with the station opened in Workbench, right-click the NtpPlatformServiceQnx and select Views > SpyRemote. Keep in mind that the ntpd is a QNX process; thus Niagara has no control over what it reports.

Ntp Platform Service Editor Qnx Time Servers

Each entry in the Time Servers list specifies a server to which the host’s clock synchronizes when the service is Enabled (true), and Sync Local Clock to NTP is also true.

This also applies to any Niagara Portability Controller that implements NTP.

Controls below the list allow you to add and delete servers, as well as reorder up or down (to establish priority order, highest at top).

PropertyValueDescription
AddresstextFully qualified domain name, IP address, or host files alias for the NTP time server.
Peer Modedrop-down listPeer mode to use with the server, as either server or peer (symmetricActive).
Bursttrue or false (default)False by default. If true, when server is reachable, upon each poll a burst of eight packets are sent, instead of the usual one packet. Spacing between the first and second packets is about 16 seconds to allow a modem call to complete, while spacing between remaining packets is about two seconds.
Preferredtrue or false (default)If true, designates a server as preferred over others for synchronization. Note also that priority order (top highest, bottom lowest) is also evaluated if multiple servers are entered.
Min. PollnumberMinimum poll interval for NTP messages, from 4 to 16. Units are in “log-base-two seconds,” or 2 to the power of n seconds (NTP convention), meaning from 2 to the 4th (16 seconds) to 2 to the 16th (65,536 seconds).
Max. PollnumberMaximum poll interval for NTP messages, from 10 to 17. Units are in “log-base-two seconds,” or 2 to the power of n seconds (NTP convention), meaning from 2 to the 10th (1,024 seconds) to 2 to the 17th (131,072 seconds).

Actions

  • Sync Now defines the fully-qualified domain name of a public NTP server or else the IP address of any accessible NTP server. Use this action only to verify that a provided NTP server is reachable and responding. You cannot use this action while NTP is enabled.