How to install and configure Cogent DataHub

WHEN TO USE THIS

Use this guide if:

• You are connecting an OPC UA server to Factbird.
• You are using Cogent DataHub as the data gateway.
• You need to publish production data to Factbird using MQTT.

PREREQUISITES

Before starting:

• Cogent DataHub has been downloaded.
• You have access to an OPC UA server (for example, Kepware).
• Factbird has provided the MQTT host, client ID, topic, and client certificate.
• You have permission to configure the OPC UA server and Cogent DataHub.

STEPS

1. Install Cogent DataHub™

   • Run the Cogent DataHub installer.
   • Select the required components:
     • OPC UA (Unified Architecture)
     • MQTT Client

   • Complete the installation.
     
     
     
     
     
     
     
     

      

   Note

   • During initial setup, DataHub installs under the current Windows user.
   • For production environments, Factbird recommends configuring DataHub to run as a Windows service after testing is complete. 
     

2. Configure the general settings

   • Open Cogent DataHub.
   • Disable Do not transmit insignificant changes.
     
     
     
     
      

   This ensures data is transmitted when only the timestamp changes, which is required by Factbird.

3. Configure the OPC UA connection

   • Create a new OPC UA connection.
   • Enter the OPC UA server endpoint URL.
   • Configure the required security settings.
   • Test the connection.
   • Trust the server certificate when prompted.
   • Approve the DataHub client certificate on the OPC UA server.
   • Test the connection again.
     
     
     
     

   Once connected:

   • Set the Read Method to Synchronous Cache Read.
   • Optionally configure a Data Domain Name.
   • Select the OPC UA nodes that should be transferred to Factbird.
     
     
     
     
     
      

4. Configure the MQTT connection

   • Create a new MQTT Client connection.
     
     
   • Configure the connection using the values provided by Factbird:
     • Host Name
     • Port 8883
     • SSL enabled
     • Client certificate
     • Client ID
     • MQTT Topic
       
       
       

   Configure the message settings:

   • Quality of Service: At least Once (QoS 1)
   • Retain Messages: Disabled
   • Message Format: Advanced

   
   
   
   
   
   Import the Factbird MQTT message template.
    

5. <?xml version="1.0" encoding="utf-8"?> <AdvancedFormatTemplate xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">   <Name>FactBirdPub AWS</Name>   <Parser>     <Name>FactBirdPub</Name>     <ReceiveProcessingScript>app.ProcessJson();</ReceiveProcessingScript>     <EnableReceiveProcessor>false</EnableReceiveProcessor>     <EnableSendDocument>false</EnableSendDocument>     <IsEnabled>true</IsEnabled>     <IsDefaultPublisher>true</IsDefaultPublisher>     <PublishFormats>       <JsonPublishFormat>         <Name>FactBird</Name>         <Text>&lt;% var JTimestamp = DateTime.UtcNow.ToJsonTime(); %&gt; {   "values": [   &lt;%                   var point; var i; for (i = 0; i &lt; points.Length; i++)                   {                     point = points[i];                                   v__output.Append(i == 0 ? "" : ",");%&gt;{                                        "id": "&lt;%= point.BaseName %&gt;",             "v": &lt;%= point.JsonValue %&gt;,             "t": &lt;%= point.JsonTimestamp %&gt;,             "q": &lt;%= (int)point.Quality &gt;= 192? "true":"false" %&gt;                                 }                 &lt;% } %&gt;],                 "timestamp": &lt;%= JTimestamp %&gt; }</Text>         <IsMultiPoint>true</IsMultiPoint>         <IsDefaultPublishFormat>true</IsDefaultPublishFormat>       </JsonPublishFormat>     </PublishFormats>   </Parser> </AdvancedFormatTemplate>

   
    

6. Apply the new Template. The “Publish” tab should now contain the script.
   
    
7. Verify the data transfer
   • Open View Data to confirm values are being received from the OPC UA server.
   • Verify data is being published to Factbird.
     

8. Configure event data (optional)

   If automatic stop causes or other event-driven features are required:

   • Create a second OPC UA connection.
   • Configure the Read Method as Subscription.
   • Create a second MQTT connection.
   • Use the plc/event/<client-id> topic.
   • Configure the separate client certificate and Client ID supplied by Factbird.
     
     
     
9. Deploy to production
   • Verify the configuration.
   • Configure Cogent DataHub to run as a Windows service.
   • Restart the service if required.

EXPECTED RESULT

After completing these steps:

• Cogent DataHub is connected to the OPC UA server.
• Production data is published securely to Factbird using MQTT.
• Event data is available if configured.
• Data continues to be transmitted after restarting the Windows service.

TROUBLESHOOTING

Issue: The OPC UA connection test fails.

• Try: Verify the endpoint URL.

• Try:Trust the server certificate.
• Try:Approve the DataHub client certificate on the OPC UA server.

Issue: Data is visible in OPC UA but not in Factbird.

• Try: Verify the MQTT host, topic, Client ID, and certificate.

• Try: Confirm Synchronous Cache Read is configured.
• Try: Ensure Do not send insignificant changes is disabled.

Issue: Changes do not take effect.

• Try: Click Apply after making configuration changes.

• Try: Restart Cogent DataHub if required.

STILL NEED HELP?

Contact Support and include:

• Your Cogent DataHub version.
• The OPC UA server type.
• Screenshots of the OPC UA and MQTT configuration.
• The Event Log.
• Any connection error messages.

RELATED ARTICLES

• User guide - Connecting OPC server
• Setting up Kepware