81 - Unit Test Helper Module (Registry) on Apache Dubbo

81-1 - ZK Startup Exception

Mon, 01 Jan 0001 00:00:00 +0000

Possible Causes

There is a compatibility issue between the server version of ZK and the client version, preventing connection.
The ZK service is not started properly, or it cannot provide services externally due to firewall or other reasons.

Troubleshooting and Resolution Steps

Confirm that the client version matches the server version.
Ensure that ZK can start normally and provide services externally.

You can analyze stack information using third-party tools or jstack [PID] > jstack.log for the diagnosis.

81-2 - ZK Destruction Exception

Mon, 01 Jan 0001 00:00:00 +0000

Possible Causes

The current instance has been destroyed completely.
Network issues or disconnections.

Troubleshooting and Resolution Steps

You can use some third-party tools or jstack [PID] > jstack.log to analyze the stack information for diagnosis.

81-3 - Unable to download file via URL

Mon, 01 Jan 0001 00:00:00 +0000

Possible Reasons

The URL mapping file does not exist.
The URL cannot be connected.

Troubleshooting and Resolution Steps

Check if the URL mapping file exists.
Verify if it can be accessed normally through a browser or other tools.

81-4 - Embedded ZooKeeper Runtime Exception

Mon, 01 Jan 0001 00:00:00 +0000

Possible Causes

The ZooKeeper service is running abnormally or has crashed.
The version of the ZooKeeper client is incompatible with the version of the server and cannot connect.
The application server is disconnected from the ZooKeeper service.
Restricted firewall or third-party protection tools.

Troubleshooting and Resolution Steps

Check the health status of the ZooKeeper service and the server it is on.
Check for compatibility issues between the ZooKeeper client version and the server’s startup version, keeping the versions consistent.
Check if the port between the application server and the ZooKeeper service is open.
Check the settings of the firewall or third-party protection tools to see if they have been blocked.