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Version: v4 (Stable)

Data Server Properties

This box defines the properties of a data server.

See also: Data Server Definition

Identification​

Identifier​

The data server identifier is a unique name among the defined data servers. It is used as the alphanumeric identifier of the data server in strings containing a reference to the data server. This is notably the case in the alphanumeric identifier of a tag which is expressed in the form:

<Data server identifier>. <Identifier of the variable in the data server>.

Because the identifier of the data server is used as an external reference, it is preferable not to modify it. It is however possible to modify it by first clicking on the button to allow editing of the edit field.

Display name​

Enter in this field the name that will be displayed in the ALERT tree to designate the data server. If no name is defined, the name displayed will be the identifier of the data server defined above.

The displayed name is multilingual. The language selected for input is the language selected for the user interface (see General display options).

Icon​

The icon displayed is the one that is used to represent the data server in the ALERT tree. Click on the "Edit" button to select a new graphical representation of the data server.

Connector​

Type​

This field displays the type of connector used by the data server. Once defined, this type can not be changed.

The "Configuration" button allows you to configure the global settings of the connector that are independent of the defined source. It is validated only if the connector has such parameters.

The "Initialization" button resets the connector. It is enabled only if the connector accepts this command.

The "Importation" button allows you to call the import module of the selected connector to import tags. It is validated only if the connector handles tag importation.

Source​

This field displays the selected data source for the data server. To modify this source, click on the button to the right of the field. This button is enabled only if the connector allows modification of the source.

To view and modify the properties attached to the source, click on the "Properties" button. This button is enabled only if the connector has source-specific properties.

Data sources​

When a data source is specified for the selected connector, this tab defines the path(s) to the data source in question, under the form of a URL describing the full path to the source for each server hosting a replication of the source.

If it is allowed by the connector, it is possible to define one or more redundant servers for the data source. If a server stops responding, ALERT automatically selects the next server from the list. The selected server at a given time is indicated by the ">" symbol in the first column of the list. You can change the order of the list by clicking on the buttons and to the right of the list.

Edit​

Click on this button to change the path to the server (URL) selected in the list.

Add​

Click on this button to add a redundant server for the data source. The URL for accessing this redundant server will be added to the list.

This button is enabled only if the connector is capable of handling redundant sources.

Delete​

Click on this button to delete the selected server (URL) from the list. The base server (1st server in the list) can not be deleted.

Properties​

Click on this button to configure the specific properties of the data source, regardless of its location.

Synchronized list in redundancy​

This check box indicates that the list of servers is synchronized or not. Uncheck this box if the list of servers is not the same on redundant stations.

Options​

This tab displays options that are predefined in the general options of the application and that can be redefined at the data server level. When the "Default" check box is selected, the corresponding parameter retains the value of the default option defined at the level of the parent grouping (if it exists) or of the default general option.

Polling parameters​

Redefinition of the parameters defined in the default options of the parent grouping (if it exists) or in the general supervision options (see Supervision options).

  • Timeout to restart polling (sec): Timeout triggered when the connection with the data server breaks before attempting to restore it. If this value is zero, there is no automatic restoration of the connection with the data server.

  • Response timeout (sec): Maximum waited time for each polled tag on the data server.

  • Read if not notified after subscription: Option to read tags that have not been notified after being polled (see Supervision options).

  • Polling activation: This option authorizes the active polling of the data source when the station is not active (redundant station). This option avoids double scanning on redundant workstations, thus reducing network load. It can be combined with the alarm synchronization option to maintain control over alarms (display, acknowledgment) on the inactive workstation.

Redefinition of the parameters defined in the default options of the parent grouping (if it exists) or in the general supervision options (see Supervision options).

  • Tag link failure if invalid value (quality "bad"): This option allows a link failure to be declared at the tag level ( displayed on the line of the tag in the list) when the value of this tag is not valid despite a good connection, following for example a bad quality indication in OPC.

  • Handling tag link failure: This option allows you to define the default processing to be performed when tags of the data server are declared in link failure ( displayed on the line of the tag in the list).

    Select the desired processing from the drop-down list:

    • No processing

    • Reconnection attempts The software will attempt to reinitialize the link with the tags declared in link failure, cyclically according to the defined "timeout to restart polling" (if this timeout is not zero).

    • Data server link failure (reconnection attempts) The data server will be declared to be in link failure ( displayed on the icon of the data server in the tree) and the software will attempt to reinitialize the link with the data server and all its variables, cyclically according to the defined "timeout to restart polling" (if this timeout is not zero).

Note:

A tag is declared in link failure ( displayed on the line of the tag in the list) in the following cases:

  • No response to the variable subscription from the data source, at the end of the timeout on request response defined at the level of the data server concerned.

  • Unknown variable in the data source (quality "Config error").

  • Poor quality, if the option "Tag link failure if invalid value..." is validated.

A data server is declared in link failure ( displayed on the icon of the data server in the tree) in the following cases:

  • Connection failure with data source (invalid address or non-active server application).

  • Link failure on at least one of its tags, if the option "Data server link failure..." is selected in the drop-down list.

  • All the declared tags of the data server are in link failure, or in "bad" quality if the option "DataServerFailIfAllBad" is validated.

When a data server is declared in link failure, the connection automatically switches to the next redundant source (if it is defined). If no redundant source is defined, or if none of the redundant sources is valid, the "Acquisition" LED turns red. If a redundant station is defined, and if automatic redundancy switching is enabled, the redundant station is activated.

Writing​

Redefinition of the parameters defined in the default options of the parent grouping (if it exists) or in the general options (Option.WriteDenied).

  • Writing to the source authorized: Option to transmit the values written in ALERT (by a command, a script, the API, ...). If this option is set to "No", the values changed in ALERT will not be transmitted to the server source.

Dynamic priority management​

Redefinition of the parameters defined in the default options of the parent grouping (if it exists) or in the general alarm options (see Alarm options).

  • Period for automatic increment (sec): Default value of the automatic increment cycle of the priority of an alarm of the data server awaiting to be transmitted.

Redundancy​

Redefinition of the parameters defined in the default options of the parent grouping (if it exists) or in the general redundancy options (see Redundancy options).

  • Alarm status synchronization: Default value of the alarm synchronization option for the tags of the data server.

  • Acknowledgment synchronization: Default value of the acknowledgment synchronization option for the tags of the data server.

Synchronization​

This tab displays the acknowledgment and masking synchronization options between the data source and ALERT.

  • Data source -> ALERT: Option to transmit to ALERT acknowledgments (or masks) made in the data source.

  • ALERT -> Data source: Option to transmit to the data source acknowledgments (or masks) made in ALERT.

  • User synchronization: When the operator who performed the acknowledgment (or masking) in the data source is identified and transmitted to ALERT but is not declared in ALERT, it is possible to create the operator in ALERT ("Create the user" option) or to select an operator from the drop-down list. Acknowledgment (or masking) will be assigned to the created or selected operator.

Advanced​

This tab displays advanced options of the data server.

Debug Trace​

Trace parameters for the analysis of problems detected on the data server.

  • Trace in file: Validation of the trace recording in a file.

  • Name with date: Validation of the creation of a trace file whose name contains the date.

  • Max size (kb): This edit field defines the maximum size of the file. When the file reaches this size, if the One circular file option is selected, the oldest records are deleted, if the Multiple files option is selected, a new file is created. An index is added to the name of the newly created file.

  • Max number of files: Defines the maximum number of files. When this number is reached, the oldest file is deleted.

  • Trace on screen: Validation of the display of a trace window. This trace window can also be displayed on a client computer.

  • Trace level: Maximum trace level. Higher is the trace level, more is traced information, the management of the trace levels being dependent on the implementation of the connector.

Default tag configuration (XML)​

XML string for the default configuration of tags that will be created in the data server. This string allows you to predefine some properties of created tags.

This string can be easily extracted from the file "taglist.xml" by copying the part corresponding to the predefined properties of a previously configured tag with the desired properties.

For example: "<eventcondition/>" forces the event condition of the tag to invalid.

Calls​

  • Cancel calls when stopping polling: when the polling is stopped for the data server (or for one of its alarms), this option offers the choice to stop the calls (for the data server or the alarm) or to continue the calls.

Alarms​

  • Auto ack on reset if alarm masked: This option allows masked alarms to be automatically acknowledged when they are reset. The default value for this option is set by the global option "Alarm.AutoAckOnResetIfMasked". This option can be overridden at the level of each data server tag.