Setting up XML-DA Server

Due to the major changes in IIS 7 (introduced with certain Windows operating systems), you must manually set its properties and settings to be able to connect to an OPC XML-DA Server from any client. You are also required to set up a DCOM. This topic helps you set up IIS 7 and DCOM to run OPC XML-DA servers to provide OPC data to clients.

Installation/Configuration

To properly run OPC XML-DA Server on the newer operating systems, follow these steps:

  1. Install .NET Framework 1.1 and update it with SP1. Microsoft .NET Framework 1.1 with SP1 must be installed on Windows where you want to have XML-DA Server working. Please refer to the Microsoft Download Center to download installation packages.
  2. Install an OPC Server with enabled XML-DA support (ICONICS Simulator 3.12, ICONICS Modbus Ethernet OPC Server, etc.).
  3. Reconfigure IIS 7, as described below in Reconfiguring IIS 7.
  4. Properly setup DCOM permissions for OPC Server as described below in Setting up DCOM Permissions.

Reconfiguring IIS 7

After successful installation of .NET Framework 1.1 SP1 and XML-DA enabled OPC Server follow the steps to below to reconfigure IIS7.

  1. Open the IIS 7 console by pressing WIN+R buttons and running command ‘inetmgr’.
  2. Go to the very top level in the tree control on the left-hand side.
  3. Open ‘ISAPI and CGI Restrictions’ in IIS Area.
  4. Allow ASP.NET v1.1.4322 by double-clicking a row and in the opened dialog window by checking ‘Allow extension path to execute’ checkbox.
  5. Go back to the very top level of the left-side tree again and open ‘ISAPI Filters’ in IIS Area.
  6. There add new ISAPI Filter, name it ‘ASP.NET 1.1’ and as executable enter ‘C:\Windows\Microsoft.NET\Framework\v1.1.4322\aspnet_filter.dll’.
  7. Now expand Sites -> Default Web Site in the tree control and select your XML-DA Server (e.g. Simulator-XML-DA,Modbus Ethernet-XML-DA).
  8. Open Basic Settings by clicking the option in the Action pane on the right-hand side.
  9. In the dialog window, click on the ‘Select…’ button for the Application Pool and change it to ASP.NET 1.1. Confirm all changes.
  10. Go back to the level of your XML-DA Server and select Authentication.
  11. Enable ‘Anonymous Authentication’.
  12. Press WIN+R to bring up the run dialog and restart IIS by running the ‘iisreset’ command (without quotes).

Setting up DCOM Permissions

To ensure that the server starts automatically when an OPC client application requests data from the OPC XML-DA server, you have to set lower restrictions in default DCOM setting. To properly set up DCOM, please refer to the application notes "GENESIS32 - DCOM on Windows XP and Server 2003 in a Domain" and "GENESIS32 - DCOM on Windows XP and Server 2003 in a Workgroup", where the settings are similar to those in the newer operating systems.

 

NOTE: There is a bug in IIS 7 that does not save all settings sometimes. After the restart, please try to connect any client to the XML-DA server. If it does not connect, please check all IIS 7 and DCOM settings again. Also, do not forget to properly set up the firewall.