Message Delivery Tab

Context

On this tab, you define for a notification how you want PCo to deliver notification messages.

For tag-based notifications, this tab is displayed as standard. For method notifications, the Message Delivery tab is only displayed if you have selected the Asynchronous checkbox on the Server Method Definitions tab (OPC UA server or PCo Web server) for the relevant method.

Procedure

  1. On the Plant Connectivity Management Console screen, select a notification and click on the Message Delivery tab.
  2. In the Reliability screen area, enter the required data for reliable message delivery using the following table:

    Field

    Description

    Max. Number of Retries

    You can enter the maximum number of retries here. The default value is 0. This means that the retry process is switched off for newly created notifications. In this case, the retry interval is not relevant and is therefore set to 0.

    Retry Interval (Seconds)

    Here you can specify the number of seconds before the next attempt to send the message. The default value is 0 seconds.
  3. In the Failed Message Persistence screen area, specify how you want failed notification messages to be stored. The failed messages are displayed in the agent instance on the Message Failures tab. You have the following options:

    • Keep All Messages

      Saves all failed messages.

    • Keep First Message

      Saves the first failed message and ignores subsequent messages.

    • Keep Last Message

      Saves the most recent failed message and removes previous messages.

    • Keep Messages Until Expiry

      You use this setting to specify that all failed messages that are older than the time you entered in the Delete Messages After field are to be deleted. For example, if you entered 60 min and a new failed message comes along, all stored failed messages that are older than 60 minutes are deleted.

    • Keep No Messages

      Does not save any failed messages.

  4. In the Lifetime screen area, specify how long you want messages to be kept in the queue.

    If the notification message cannot be delivered after the specified duration has elapsed, it is displayed in the agent instance on the Expired Messages tab.

  5. In the Message Bundling screen area, you can activate the message bundling function by selecting at least one of the checkboxes:

    • Fixed Number of Messages

    • Maximum Accumulation Time

    Message bundling is a procedure in which notification messages can no longer be sent individually; instead, they are bundled in one large notification message and sent together to the connected destination system.

    For more information, see Message Bundling.

  6. Select the Process Notification Messages Exactly Once in Order checkbox if you want to use this function for the notification. By selecting the checkbox, you can define that the notification messages of this notification are sent individually and exactly in the order in which you put them into the queue. For more information, see Process Notification Messages Exactly Once in Order.

Next Steps

Agent Instance: Displaying Messages.