When you see the message “kafka node -1 disconnected”, it indicates that the Kafka broker with the ID “-1” has disconnected from the cluster. This can occur due to various reasons such as network issues, server failure, or misconfiguration.
To resolve this issue, you need to investigate the cause of the disconnection and take appropriate actions. Here are some steps you can follow:
- Check the network connectivity: Ensure that there are no network connectivity issues between the disconnected Kafka node (-1) and the rest of the cluster. Network interruptions or firewall rules can lead to disconnections.
- Verify server availability: Make sure that the Kafka broker with ID -1 is running and reachable. Check if the server hosting this broker is functioning correctly and not overloaded.
- Review Kafka configuration: Check the Kafka configuration file (e.g., server.properties) to ensure that the broker configuration is accurate. Verify that the broker ID (-1) is correctly assigned and matches the node it represents. Also, check for any misconfiguration related to network settings or advertised listeners.
- Inspect Kafka server logs: Look into the Kafka server logs to identify any error messages or warnings related to the disconnected node. These logs can provide valuable insights into the cause of the disconnection.
Here’s an example of how the troubleshooting process might look like:
- Check the network connectivity by trying to ping the IP address of the disconnected Kafka node (-1). If the ping fails, investigate the network infrastructure and firewall settings.
- SSH into the server hosting the Kafka broker with the ID -1 and verify if the Kafka process is running. Run the command “ps aux | grep kafka” to check for any running Kafka processes.
- Open the Kafka configuration file (e.g., server.properties) and confirm that the broker ID (-1) matches the actual node that is disconnected.
- Browse through the Kafka server logs located in the log directory (as specified in the configuration file) and look for any error messages or warnings related to the disconnected node.
By following these steps and investigating the specific details of your Kafka setup, you can determine the cause of the disconnection and take appropriate actions to resolve it.