• A server may encounter problems without any user (or developer) noticing anything.
  For example:
  • a scheduled task may fail.
  • an automatic backup may fail.
  • a node may become inactive in an HFSQL cluster, ...
• A server can also perform operations automatically (automatic update, search for keys to optimize the queries, ...). The implementation and the status report of these operations require a notification.

• see the history of incidents/notifications that occurred on the server. For more details, see History of incidents/notifications.
• be informed in case of incident (by email or via the messaging of Control Centers). For more details, see Receiving the notifications (by email or WDBal).

Overview

• Date and time of incident.
• Message presenting the incident.
• Category of incident: Information, Warning, Critical, Error.
  • Information: Information about the events that occurred on the server.
    Example:
    • Automatic update of HFSQL server with reboot.
    • Suggestion for adding keys and composite keys to optimize the execution time of queries.
  • Warning: Events that do not trigger a failure but about which something must be done.
    Example: Resolution of a modification conflict for the replication. If several of them occur, the architecture of the application may have to be changed (otherwise, there is no need to worry).
  • Critical: Failures for which no error can be returned to the user.
    Examples: WLanguage error in a stored procedure used by a scheduled task, failure of the connection to a replicated server, ...
  • Error: Problem regarding the management of Windows cache.

• from the HFSQL Control Center.
• programmatically.

History of notifications displayed in the HFSQL Control Center

1. Start the HFSQL Control Center.
2. Select the requested server.
3. Go to the "Notifications" tab.
4. The list of notifications sent by the server is displayed. You can:
   • delete a notification.
   • refresh the list.

Accessing the history of notifications programmatically

PROCEDURE HFCS_RetrieveLastNotifications(sServer, sUser="Admin", sPassword=""): string
// Parameters for connecting to the server whose last notification must be retrieved
ctConnection is Connection
ctConnection.Provider = hAccessHFClientServer
ctConnection.Server = sServer
ctConnection.User = sUser
ctConnection.Password = sPassword
ctConnection.Database = "__System"

// By default, don't return anything
RETURN = ""
// Files of server notifications
dsAlert is Data Source
IF HDeclareExternal("Alert.fic", dsAlert, ctConnection) THEN
	// Last notification in date
	IF HReadLast(sdAlert, date) THEN
		// Retrieves the record
		RETURN = HRecordToString(sdAlert)
	END
	// Frees the declared file
	HCancelDeclaration(dsAlert)
	// Frees the connection
	HCloseConnection (ctConnection)
ELSE
	// Failure accessing the server
	Error("Error while retrieving the notifications: " + HErrorInfo(hErrFullDetails))
END

Overview

• via the HFSQL Control Center.
• programmatically.

HFSQL Control Center

1. Start the HFSQL Control Center.
2. Select the requested server.
3. In the ribbon, in the "Parameters" group, click "Server configuration".
4. In the list of possible configurations, click "Notifications". The window for configuring the notifications is displayed:
   
5. Configure the modes for sending notifications:
   • in the "Send by email" tab, specify the characteristics of the SMTP server that will be used to send the notifications by email.
   • in the "Send by messaging (WDBal)" section, specify the characteristics of the database of Control Centers that will be used to send the notifications.
   Remarks:
   • The "Retrieve the computer configuration" button is used retrieve the configuration of the current computer.
   • The database of Control Centers can be in Classic or in Client/Server mode.
6. Create the recipients of notifications:
   • The button is used to add a recipient for the sending by email. Specify the email address of the recipient and validate.
   • The button is used to add a recipient for the sending via the messaging (WDBal) of Control Centers. Select the relevant recipients and validate.
   • In the list of recipients, for each recipient, select the minimum severity level of the incidents for which you want to send notifications.
7. Click the "Apply" button to validate the configuration.

Programming