Failed to connect to Azure event hub(AEH) from Java using kafka client

@Kalikiri, Karthik - Thanks for the question and using MS Q&A platform.

It seems like you are facing an issue while connecting to Azure Event Hub from Java using Kafka client. The error message you provided indicates that the connection is being reset by the AEH server.

To troubleshoot this issue, you can check the logs of your Kafka client application. You can also check the logs of the AEH server to see if there are any errors or warnings related to the connection.

Additionally, you can try the following steps to resolve the issue:

• Check if the connection string used by your Kafka client application is correct and has the necessary permissions to access the AEH namespace.
• Check if the firewall rules are configured correctly to allow traffic from your Kafka client application to the AEH namespace.
• Check if the SSL/TLS certificate used by your Kafka client application is valid and trusted by the AEH server.
• Check if the Kafka client application is using the recommended configurations for connecting to AEH. You can refer to the following document for the recommended configurations: https://docs.microsoft.com/en-us/azure/event-hubs/apache-kafka-configurations

If none of the above steps resolve the issue, you may open a support ticket for further assistance.

I hope this helps! Let me know if you have any further questions.

@PRADEEPCHEEKATLA-MSFT Thank you for your response, I am opening a support ticket but below are the answers to your questions

• Check if the connection string used by your Kafka client application is correct and has the necessary permissions to access the AEH namespace.

     **yes, it's correct, application successfully authenticated as per logs shared**
  

• Check if the firewall rules are configured correctly to allow traffic from your Kafka client application to the AEH namespace.

    **There is no firewall and TLS handshake was completed and java application authenticated**
  

• Check if the Kafka client application is using the recommended configurations for connecting to AEH.

    **Application is not using TLS client certificate but access key. Authentication works as per     logs shared.**
  

@Kalikiri, Karthik - Thank you for providing the additional information. It's good to know that the connection string and firewall rules are correct, and that the Kafka client application is using the recommended configurations for connecting to AEH.

Since the issue still persists, it's a good idea to open a support ticket with Azure support. They will be able to investigate the issue further and provide you with a solution.

In the meantime, you can also try the following steps:

Check if there are any network issues between your Kafka client application and the AEH namespace. You can use tools like ping and traceroute to check the network connectivity.

Check if there are any issues with the Kafka client application itself. You can try running the application on a different machine or network to see if the issue persists.

Check if there are any issues with the AEH namespace. You can try creating a new AEH namespace and connecting to it from your Kafka client application to see if the issue persists.

I hope this helps! Let me know if you have any further questions.

@Kalikiri, Karthik - We haven’t heard from you on the last response and was just checking back to see if you have a resolution yet. In case if you have any resolution please do share that same with the community as it can be helpful to others. Otherwise, will respond with more details and we will try to help.

@PRADEEPCHEEKATLA-MSFT We are working with the support team, will update here once we have a complete resolution.