Synchronization Schedule dialog box

Clicking the Sync Schedule command opens the Synchronization Schedule for interface dialog box:

The Synchronization Schedule area configures whether the Sync Engine initiates synchronization scans for the interface on a periodic schedule. If Synchronize automatically using the following schedule is selected, the Period boxes specify how often the Sync Engine runs a synchronization scan for the interface.

Note: Even though scheduling may be automatic, the handling of differences between PI points and data source tags is still subject to the settings on the Rules dialog box. They may not necessarily be automatic.

When an interface is registered with PI APS, automatic scheduling is the default selection and the default period is a recommended interval built into the PI APS Connector for the interface. The synchronization period may be changed to an interval appropriate for your environment. You can restore the default synchronization period at any time by clicking the Use Default button.

Changing an enabled interface's configuration from manual to periodic scheduling can have a side effect: if the interface has not been synchronized since the Sync Engine last started, the first periodic synchronization scan for the interface is initiated when the periodic scheduling setting is applied.

The Do not synchronize automatically button prevents periodic scheduling of synchronization scans for the interface. When this button is selected, synchronization scans only occur when initiated by clicking Sync Now on the toolbar or by the PI APS Synchronization Trigger service.

Note: Most users choose the Synchronize automatically using the following schedule option. Unless synchronization triggers are configured, the second option requires you to click Sync Now on the main window toolbar to start a synchronization scan.

The Synchronization Trigger area configures and displays the conditions that the PI APS Synchronization Trigger service monitors. The PI APS Synchronization Trigger service can monitor the file system on the PI APS computer for changes to existing files or creation of new files. When the condition for a trigger occurs, the PI APS Synchronization Trigger service sets the SyncImmediately flag for the interface instance, which notifies the Sync Engine that a synchronization scan is needed. See section Synchronization scheduling for additional information.

The Sync Trigger Configuration area either defines the conditions to monitor for a new trigger or edits an existing trigger.

Every trigger for an interface instance must have a unique name. Enter a name for the trigger in the Name box.

Presently, the PI APS Synchronization Trigger service only monitors file system events and, therefore, File is the only choice in the Type list. In future releases, other choices may be added.

For a File trigger, enter the full path to the file to monitor in the Trigger on box. The directory part of the path in this box must be an existing directory. The file name part of the path can contain the name of a specific file or may contain wildcards. If the file name part contains wildcards, all files in the last directory in the path that match the pattern are monitored. To assist in construction of the path in this box, click to open the Path Builder dialog box.

In the Path Builder dialog box, click a folder in the list. The path to the selected folder replaces the directory part of the path in the Full Path box. The File Mask box sets the file name part of the path in the Full Path box. To monitor specific files, change the File Mask box to a pattern that matches the file names or a file name with no wildcards. If the File Mask or Full Path box is invalid (for example, the File Mask box contains illegal characters), the background changes to yellow.

When the Full Path box shows the path you want, click OK to close the dialog box and transfer the path into the Trigger On box in the Synchronization Schedule for interface dialog box.

Returning to the Synchronization Schedule for interface dialog box, the Attribute list contains these choices:

• File Changed: The PI APS Synchronization Trigger service monitors the modification time property of files that match the path in the Trigger On box. When a file modification time property changes, the SyncImmediately flag is set for the interface instance. Any write to a file, even if the file contents are not actually changed, updates the file modification time property.

• Size Changed: The PI APS Synchronization Trigger service monitors the size property of files that match the path in the Trigger On box. When a file size property changes, the SyncImmediately flag is set for the interface instance.

• File Created: The PI APS Synchronization Trigger service monitors the last directory in the path in the Trigger On box. When a file is created that matches the file name part of the path, the SyncImmediately flag is set for the interface instance.

If a trigger event occurs while the PI APS Synchronization Trigger service is not running, the event is lost. When the PI APS Synchronization Trigger service starts, it loads all configured triggers. However, it does not know if a synchronization scan should be initiated for possibly lost trigger events. Select the Sync once on startup check box to configure the PI APS Synchronization Trigger service to assume that trigger events occurred while it was not running. When the PI APS Synchronization Trigger service loads a configured trigger with Sync once on startup selected, the SyncImmediately flag is set for the interface instance.

While it runs, the PI APS Synchronization Trigger service loads new configured triggers and reloads edited triggers. If the Sync once on startup option is selected in these cases, the SyncImmediately flag is also set for the interface instance.

Click Add to add a new trigger to the Configured Sync Triggers list.

Note: When triggers are added, edited, or deleted, the changes are not immediately stored in the Module Database. The PI APS Synchronization Trigger service cannot see changes to triggers until you click OK or Apply to store the new trigger configurations in the Module Database. The PI APS Synchronization Trigger service reviews the Module Database every 30 seconds for trigger configuration changes.

The Configured Sync Triggers list shows the triggers that are defined for the selected interface. To change a trigger, click the trigger in the list and then click Edit. The selected trigger is loaded into the Sync Trigger Configuration area where the configuration can be changed. While an existing trigger is in the Sync Trigger Configuration area, the Save and Cancel buttons are available. Click Save to update the trigger in the Configured Sync Triggers list and end editing mode. Click Cancel to end editing mode without saving any changes to the trigger.

To remove a trigger, click the trigger in the list and then click Delete.