This driver is a simple driver. It provides additional functionality to enable Geo SCADA Expert to interface with specific supported devices using a particular protocol. To interact successfully with such devices, you need to:
- Install and run the driver
- Ensure that the driver is licensed
- Configure the required database items and settings on the driver
- Ensure that the database items (and any database items on which they depend) have valid, saved, configuration and are 'In Service'.
Intended Audience
This guide is designed for use by engineers who are responsible for configuring NTP-related settings. It can also be used by system administrators who can use the NTP driver’s diagnostic features for fault finding.
Document Scope
This guide explains how to configure Geo SCADA Expert’s NTP Driver to monitor a Network Time Protocol (NTP) server. It also provides information on NTP stratum ranking and the NTP driver’s diagnostic features.
Prerequisite Reading
This guide contains technical information that is intended for users that are sufficiently familiar with Geo SCADA Expert configuration and operation. Before reading this driver guide, ensure that you are familiar with:
- Geo SCADA Expert configuration practices, procedures, and the configuration of properties that are common to many database items. For more information, see the Geo SCADA Expert Guide to Core Configuration, and the Geo SCADA Expert Guide to Core Point Configuration.
- Driver structure, components, and configuration properties, pick actions, and status attributes that are common to many drivers. For more information, see the Geo SCADA Expert Guide to Drivers.
- Simple driver composition, configuration order, and configuration properties and logging options that are common to many simple drivers. For more information, see the Geo SCADA Expert Guide to Simple Drivers.
The Network Time Protocol (NTP) is an Internet protocol that is used for synchronizing the system clocks on computer systems. The Geo SCADA Expert NTP Monitor Driver monitors the accuracy of such synchronization.
We recommend that you run NTP, or an equivalent time synchronization mechanism, on your Geo SCADA Expert system. This will synchronize the system clocks of the computers on your system.
If required, on systems that are running NTP, you can also run the Geo SCADA Expert NTP Monitor Driver and configure NTP Monitor items in the database to enable you to assess the accuracy with which those system clocks are being synchronized.
This Guide to the NTP Monitor Driver explains:
- How to configure NTP Monitor-specific features and items in the Geo SCADA Expert database (see Configuring NTP Monitor Devices in Geo SCADA Expert).
- The stratum ranking that affects the accuracy with which system clocks are synchronized (see Understanding NTP Stratum Ranking and how this Affects Clock Accuracy).
- NTP Monitor-specific aspects that may be of interest to system administrators and engineers when investigating unexpected system behavior (see NTP Monitor Specific Status Display Attributes).
NOTE: There are no driver-specific pick actions for database items on this particular driver. However, users with the required privileges can add custom pick actions to a database item by using the User Methods tab on the relevant configuration Form (see Using the User Methods Tab to Define Custom Actions in the Geo SCADA Expert Guide to Core Configuration). See a system administrator for the documentation associated with such custom actions (also known as ‘methods’).
On the Modules tab of the Geo SCADA Expert Server Status Tool, this particular driver is listed as the NTP driver. The logging options that are available to the driver are common to many simple drivers—for information, see Driver Log File Options that are Common to Many Simple Drivers in the Geo SCADA Expert Guide to Simple Drivers.
ATTENTION: This note only applies to machines that are running Windows Server 2012 R2 or earlier versions of Windows. With such versions of Windows, the W32Time service is not a full-featured NTP solution. Therefore, for high accuracy environments (such as ones in which time needs synchronizing to within an accuracy of 1 to 2 seconds), use an NTP client to maintain accurate time, and disable Windows Time (W32Time).
Windows Time uses the Simple Network Time Protocol (SNTP), which is a simplified version of Network Time Protocol (NTP). As such, high accuracy tolerances such as that mentioned above are outside of the design specification of the W32Time service. For more information, see https://support.microsoft.com/en-us/kb/939322.
(With computers that are running Windows Server 2016 and newer operating system versions, high accuracy time can be achieved using W32Time, providing that certain criteria are satisfied. For more information, see https://support.microsoft.com/en-us/kb/939322.)
For information on running NTP (as oppose to the NTP Monitor driver) and on synchronizing system clocks using NTP, see the NTP website (http://www.ntp.org).