Converting a Lookout Server Process Into a Client

You can create a client process separate from the server, or you can create a client process by converting an existing server process. This document describes how to convert a server process to a client process. The general guidelines for client processes are as follows:
· Client processes should not connect directly to hardware, and they should not contain any driver objects.
· Client connections should be made to the server process using absolute paths.
· Controls in a client process should be configured to work in an appropriate way with the server process.

Follow the steps in this document to ensure that your client process follows these guidelines.

Step 1. Create a Working Copy

You must make a copy of your server before you make changes.

Caution: Use caution if you must rename, change, or close processes that are already in operation. It is best to follow these steps only when a system is still in the development stage.
1. Launch Lookout and open your server process.
2. Select Object»Object Explorer.
3. Right-click on the server process, and select Properties.
4. Enter a new name for the client process and click OK.
5. Select File»Save As and be sure to save the process with a new client name—something different than the original server process name.
6. Select File»Open to open the original server process file again.
7. To distinguish client control panels from the original server control panels, change the title bars on each panel as follows:

a) Expand the Object Explorer view of the client process.
b) One at a time, right-click on each control panel object, select Properties, and change the Title field to reflect that this control panel is part of the client process, not the server process.

Step 2. Delete Driver Connections, Dependencies, and Objects

You cannot have driver objects in your client process. Driver objects are objects that connect to your hardware—they are listed under Object»Create»Drivers.
1. Reopen your original server process so that you can make changes to the new client without affecting the processes controlled by the server.
2. Using the expanded view of the client process in the Object Explorer, right-click on a driver object and select Edit Connections.
3. In the connections dialog box, double-click on an item in the upper-right Existing connections section.
4. Click on Clear, then Accept. The dialog box shows “Connection deleted”, and the item disappears from the Existing connections list.
5. Repeat steps 3 and 4 for each existing connection, until there are no more existing connections, then click on the Quit button.
6. Repeat steps 2-5 until every connection to every driver object is cleared in the client process.
7. Select Object»Connection Browser and expand the view to see the list of objects in the client process.
8. For each driver object that is not grayed out, double-click on the object to see its input and output connections, which are shown in bold, with icons, in the left and right columns. These inputs and outputs are objects that reference the driver directly.
9. Right-click on an input or output object of a driver in the Connection Browser and choose Properties.
10. For each field in the dialog box that points to a driver object (often a yellow field), right-click and change the current path to an absolute path that points to that object in the server process. The absolute path takes the following form: \\servercomputername\processname\foldernames\driver.datamember where servercomputername is the network name of the computer running your server process; processname is the name of the server process; foldernames is the path through any folders that might contain the driver object in the target server process, separated by backslashes (such as folder1\folder2); and driver.datamember is the full name for the data member you want to display. (NOTE: A symbolic link should be used instead of absolute paths if your version of Lookout supports symbolic links. First, a link to the server process should be created in the client process. Then, all connections should be made to the link, rather than the driver objects. Please see the Lookout help files for additional information.)
11. Check to see if you still have any objects connected to the driver in the Connection Browser. If so, they are probably expressions (displays). Locate the expressions on the control panel, right-click and choose Object Properties, and change the paths to absolute paths as explained in step 10.
12. Repeat steps 7 through 11 for every input/output of every driver object in the client process.
13. Using the expanded view of the client process in the Object Explorer, right-click on each driver object and select Delete, until all driver objects are deleted from the client process.

Step 3. Convert Your Controls

Client control objects (Pot, Pushbutton, Radiobutton, Switch, and TextEntry objects) must be configured to operate appropriately with respect to the server process. You have several options for converting controls, as follows:
· If you do not want the client process to display a control or its value from the server process, simply delete the control from the process following these steps:

1. Select the control object on the client panel and press <Delete>.
2. Using the expanded client process view of Object Explorer, right-click on the control object and select Delete.

· If you want to permit an operator of the client process to view and manipulate a control that is part of the server process, follow these steps:

1. Using the expanded client process view of Object Explorer, right-click on the control object and select Properties.
2. Select Remote instead of Local in the Position source section of the dialog box, and enter the URL of that same control in the server process.

· If you want an operator of the client process to see a control value that is part of the server process but not be allowed to manipulate it, here are two options:

– Delete the control and insert an expression in its place following these steps:
1. Select the control object on the control panel and press <Delete>.
2. Using the expanded client process view of Object Explorer, right-click on the control object and select Delete.
3. Select Insert»Expression and use an absolute path in the dialog box.

– Change the properties of the client object so that it is set to a Remote Position source, as explained under the second bullet item in this section, then set its security level higher than that of the operator. Refer to your Lookout documentation for information on security.

Step 4. Save, Move, and Test Your Client

Follow these steps to prepare your client for operation.
1. Install a copy of your new client process on another networked computer that is running Lookout. You must copy the process files to the other computer.
2. Launch the client process on the other computer.
3. Select Alarms»Filter Options, and choose to show both Alarms & Events in the dialog box.
4. Monitor the events and alarms that show up in the alarm window.
5. Open and examine each control panel to find any data quality problems. A red X superimposed on any display is a warning about a data quality problem. Right-click on any such object and
6. examine its path, or use the Connection Browser to locate the connections and correct the problems.
7. Configure your control security and network security appropriately. Refer to your Lookout documentation for information on security configuration.
8. Make sure your Lookout system is registered to support the use of your new client. Select Options»System and click on the Change Client License button to view your client license information. Contact National Instruments if you need to add authorized client connections for Lookout, then return to the Client licensing dialog box and click on the Add button.
9. Save all of your processes, and put your new client into operation.

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