Installing DataHub v7 on a system running v6

Running Cogent DataHub v7.0 and OPC DataHub v6.4 on the same computer

Cogent DataHub v7.0 is designed to install and run side-by-side with OPC DataHub and Cascade DataHub v6.4 on the same computer. In order to do this, v7.0 maintains its own independent configuration. If you want to carry your v6.4 configuration forward to v7.0, you must copy your existing configuration to the v7.0 configuration directory. When v7.0 first runs, it will ask you whether you want to make a copy of your existing configuration. If you answer “Yes” then your existing configuration will be copied and upgraded to the v7.0 format. Please note: If you copy the configuration, you will need to change some of the defaults. Since DataHub v6.4 and Cogent DataHub v7.0 provide many features in common, their default configurations will conflict when they are run at the same time. In addition, in order to support the added features of v7.0, the default TCP port values have changed. This can potentially cause the WebView subsystem in v7.0 to fail until the configuration has been modified. Even if you choose not to copy the v6.4 configuration, there are some possible conflicts you should know about when running both versions on the same computer.

Affected subsystems in DataHub v7.0

  • Tunnel/Mirror: Due to limitations placed on TCP port numbers by Microsoft Silverlight, the default port number for the Tunnel/Mirror subsystem has changed from 4600 to 4502.
  • Web Server: Cogent DataHub version 7.0 installs the updated HTML files and all of the supporting files for DataHub WebView in a directory that is separate from v6.4.
  • Web Server: Cogent DataHub v7.0 and DataHub v6.4 both attempt to listen to port 80 for HTTP requests.
  • OPC Server: OPC DataHub v6.4 and Cogent DataHub register different PROGIDs. OPC client configurations will need to be updated.
  • DDE Service Name: OPC DataHub v6.4 and Cogent DataHub both declare the same DDE service name, “datahub”. You will need to change one of the service names if you are running both DataHub versions on the same computer and trying to have Excel read data from one or both of them.

Possible conflicts between DataHub v7.0 and v6.4

If you choose to copy the v6.4 configuration
When you copy the v6.4 configuration to v7.0, it will preserve the TCP port numbers and web server document root path from your v6.4 configuration. This will mean that DataHub WebView will not be able to run until you make the following changes.

  1. TCP port numbers – In order to have programs like WebView work correctly, you will need to change the TCP port numbers in your v7.0 configuration.
    1. Run the Cogent DataHub v7.0
    2. Open the Tunnel/Mirror properties tab and change the Tunnel/Mirror Master port settings to 4502 (plain-text) and 4503 (secure) respectively.

    Please note: The TCP port conflict only occurs if both the v7.0 and v6.4 DataHubs are configured to accept incoming TCP connections on the same port number. In other words, if you have both your v7.0 and v6.4 DataHub listening on the same TCP port number. If you are only making outgoing TCP connections (for example, you only make tunnel/mirror slave connections out to a DataHub running on another computer), then the v7.0 and v6.4 configuration for your outgoing slave connections can have the same TCP port number defined for the master DataHub.

  2. Web server document root directory – In order to start WebView or the other web demos, the web server root directory for v7.0 will need to be changed to point to the Cogent DataHub installation directory instead of the v6.4 install directory:
    1. Open the Web Server tab and change the document root directory to:
      C:\Program Files\Cogent\Cogent DataHub\plugin\WebServer\html
    2. The path for the Error log, Access log and SSL certificate file may also need to be changed as well.
  3. Web server port number – In order to avoid a conflict between the v6.4 web server and the v7.0 web server one of them needs to be using a different port number:
    • To change the web server port number, open the web server tab and change the port number from the default port 80 to another number, such as 81.

If you choose NOT to copy the v6.4 configuration
Even if you choose not to copy over the v6.4 configuration files, you need to understand that there may be a possible conflict if you want to run both v6.4 and v7.0 at the same time, on the same computer. Specifically, this is related to the DataHub web server that comes with each version. You cannot have two programs using the same TCP port, so you will need to configure one of the DataHub’s web server to use a different port number.

  1. Web server port number – In order to avoid a conflict between the v6.4 web server and the v7.0 web server one of them needs to be using a different port number:
    • To change the web server port number, open the web server tab and change the port number from the default port 80 to another number, such as 81.
  2. DDE service name – If you are running both OPC DataHub v6.4 and Cogent DataHub v7.0 on the same computer then both of them will declare the same DDE service name, “datahub”. If you then try to drag and drop data from the DataHub into Excel, you may find that Excel reports a conflict. The solution is to change the service name in one of the DataHub configurations:
    • To change the DDE service name, open the DDE tab, select the DDE service name from the list and click the Edit button.

OPC Server Changes

Since Cogent DataHub v7.0 can be run on the same computer as OPC DataHub v6.4, they must register different OPC server names. OPC DataHub uses the PROGID “cogent.opcdatahub.1”. Cogent DataHub uses the PROGID “cogent.datahub.1”. If you are upgrading a system from v6.4 to v7.0, any OPC clients in the system must be reconfigured to attach to the PROGID of Cogent DataHub.

Copying configuration files by hand

If the configuration is not correctly copied during the first run for some reason, you can copy the OPC DataHub v6.4 configuration by hand:

  1. Stop the Cogent DataHub software.
  2. Remove all of the files in the Cogent DataHub configuration directory, except for “licenses.lic”: WinXP/2003 – c:\Documents and Settings\\Application Data\Cogent DataHub
    Windows 7 – c:\Users\\AppData\Roaming\Cogent DataHub
  3. Copy all of the files from the v6.4 OPC DataHub configuration directory into the Cogent DataHub configuration directory (except for “licenses.lic” if one already exists).
  4. Rename “Cogent DataHub\OPC DataHub.cfg” to “Cogent DataHub\Cogent DataHub.cfg”
  5. Restart the Cogent DataHub v7.0.

Resetting the Cogent DataHub configuration

If you want to reset the Cogent DataHub to its default state, you can simply delete the existing configuration files. This will not affect your configuration files for v6.4:

  1. Stop the Cogent DataHub software.
  2. Remove all of the files in the Cogent DataHub configuration directory, except for “licenses.lic”: WinXP/2003 – c:\Documents and Settings\\Application Data\Cogent DataHub
    Windows 7 – c:\Users\\AppData\Roaming\Cogent DataHub
  3. Restart the Cogent DataHub v7.0.

Contact Cogent is you have any questions

If you have any questions or concerns, please email support@skkynet.com