5 - Configuration (Central) Layer on Apache Dubbo

5-1 - Configuration Center Connection Failure

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

Possible Causes

The server where the configuration center is located is shut down or crashed.
The IP address or port number is incorrect.
A firewall is incorrectly blocking the port used by the configuration center.

Troubleshooting and Resolution Steps

Check the configuration of the configuration center’s IP address and port.
Verify whether the server is powered on and functioning properly.
Check if the firewall is allowing the port used by the configuration center.

5-2 - Failure in Registering/Unregistering Shutdown Hook Methods

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

Possible Causes

Custom hook methods may have exceptions in their business logic.

Troubleshooting and Resolution Steps

Check whether there are any runtime exceptions in the business logic of the custom hook methods.

5-3 - An unexpected error occurs when destroying method calls

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

Possible Causes

Custom destroy method, there are exceptions in business processing.

Troubleshooting and Resolution Steps

Check whether the custom destroy method has runtime exceptions in the business processing logic.

5-4 - Method not found in service interface

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

Possible Causes

The interface name/method called by the consumer does not exist.
The server has not correctly exposed the current interface.

Troubleshooting and Resolution Steps

Check whether the interface name/method called by the consumer exists.
Check whether it is listed in the services exposed by the server.

5-5 - Unable to get env variable

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

Possible Causes

Environment variables cannot be retrieved.

Troubleshooting and Resolution Steps

Check the variable name prompted to see if it is configured and can be properly read and loaded.

5-6 - Attribute conflict of interface types

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

Possible Causes

Improper configuration of the generic definition.

Troubleshooting and Resolution Steps

Check if the generic definition is correct.

5-7 - Unexpected error occurred while canceling export

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

Possible Causes

Unable to connect to the configuration center service.
The configured protocol, IP, or port is incorrect.
There is a version conflict between the configuration center client and server, preventing an effective connection.

Troubleshooting and Resolution Steps

Check if the status of the configuration center service is normal.
Verify that the configured protocol, IP, or port is correct.
Check if the version of the configuration center client in use is compatible with the server version.

5-8 - The protocol will use a randomly available port

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

Possible Causes

The port specified by the protocol is occupied, and a random port is selected for startup.

Troubleshooting and Resolution Steps

Check if the currently configured port is occupied by other applications.

5-9 - Service configuration export failed

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

Possible Causes

Unable to connect to the configuration center’s service.
Incorrect protocol, IP, or port configured.
Conflict between the version of the configuration center client and the server version, preventing a valid connection.

Troubleshooting and Resolution Steps

Check if the status of the configuration center service is normal.
Check if the configured protocol, IP, or port is correct.
Verify whether the version of the configuration center client being used is compatible with the server version.

5-10 - Service registration interface application mapping failed

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

Possible Causes

The service metadata exposed by the service does not match or has been tampered with the application.

Troubleshooting and Resolution Steps

Check whether the metadata content in the configuration center matches that within the application.

5-11 - Registration Instance Error

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

Possible Causes

The service of the configuration center cannot be connected.
The configured protocol, IP, or port is incorrect.
There is a conflict between the version of the configuration center client in use and the server version, preventing an effective connection.

Troubleshooting and Resolution Steps

Check if the service status of the configuration center is normal.
Verify that the configured protocol, IP, or port is correct.
Ensure that the version of the configuration center client used is compatible with the server version.

5-12 - Refresh instance and metadata error

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

Possible Causes

The configuration center service cannot be connected.
The configured protocol, IP, and port are incorrect.
There is a conflict between the version of the configuration center client used and the version of the server, preventing an effective connection.

Troubleshooting and Resolution Steps

Check whether the status of the configuration center service is normal.
Verify that the configured protocol, IP, and port are correct.
Check if the version of the configuration center client used is compatible with the server version.

5-13 - Unable to Destroy Model

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

Possible Reasons

Custom destroy method has exceptions in business processing.

Troubleshooting and Resolution Steps

Check whether the custom destroy method and business processing logic have any runtime exceptions.

5-14 - Model startup error

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

Possible Causes

The connection is disconnected while the service is waiting to publish or subscribe.
Network connection timeout.

Troubleshooting and Resolution Steps

Check whether the connection between the application server and the configuration center is normal.
Check for network connection timeouts or other issues.

5-15 - Model Reference Error

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

Possible Causes

The methods of Dubbo’s core handling classes are misused or have been tampered with.

Troubleshooting and Resolution Steps

Check for misuse or decompilation modifications in the application.

5-16 - Unable to find any valid protocol

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

Possible Causes

The configured protocol is not supported.

Troubleshooting and Resolution Steps

The currently supported protocols include dubbo, rmi, hessian, http, webservice, thrift, redis, etc.

See also Configuration Reference Manual

5-17 - Parameter Value Format Error

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

Possible Reasons

The configuration value length is too long, generally set to within 200 characters.
The format of the configuration value is incorrect; currently supports numbers, -, _ and others.

Troubleshooting and Resolution Steps

Check if the content of the configuration value is too long; modify according to the prompt information.
Check if the content of the configuration value contains special characters, such as @#$%^& etc.; please refer to the prompt information for modifications.

5-18 - Notification Registration Event Failed

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

Possible Causes

The notification has been sent, but an unexpected error occurred in the business processing logic.
The configuration center cannot be connected, resulting in a timeout error.

Troubleshooting and Resolution Steps

Check the custom business logic implementation for any runtime exceptions.
Check whether the configuration center can be connected normally.

5-20 - Error occurred when stopping the dubbo module

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

Possible Causes

Custom implementation of the destroy method may have runtime exceptions in business logic.
The service was not stopped gracefully, which may lead to unhandled business logic.

Troubleshooting and Resolution Steps

Check the custom implementation of the destroy method and the business logic.
Verify if there are any time-consuming business processing logic when stopping the service.

5-21 - Exception occurred when destroying the service

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

Possible Causes

The service discovery instance has been destroyed.

The current method has been deprecated since version 3.1.

Troubleshooting and Resolution Steps

5-22 - An error occurred when initializing the registry

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

Possible Causes

The address of the registry is configured incorrectly.
The configured address information cannot be connected to the network properly.
The version of the configuration center client does not match the actual server version, leading to compatibility issues.

Investigation and Resolution Steps

Check if the configured address is correct.
Check if the network is smooth and can be connected using a third-party client.
Check for compatibility matching issues, and refer to third-party websites for version adaptation.

5-23 - Waiting for export/reference service to encounter an exception

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

Possible Causes

The registration center unexpectedly stops or cannot provide normal services when exporting/referencing services.

Troubleshooting and Resolution Steps

Check whether the registration center can be connected normally, and check whether the current client version is compatible with the server version.

Exceptions are handled within the export/reference single method, so theoretically this exception should not be thrown.

5-24 - Asynchronous waiting for service reference exceptions

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

Possible Causes

The registry center has crashed or is unable to provide normal services externally.

Troubleshooting and Resolution Steps

Check whether the registry center is connectable and verify if the current client version is compatible with the server version.

5-25 - Custom implementation causes undefined exceptions

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

Possible Causes

The custom implementation of the org.apache.dubbo.rpc.Protocol protocol throws a business logic exception during the method call destroy.

Troubleshooting and Resolution Steps

Check the destroy method of the custom implementation class code.

5-26 - Metadata has been exported

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

Possible Causes

The metadata has been exported in the current JVM.

Troubleshooting and Resolution Steps

5-27 - Incorrect usage of internal class API

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

Possible Causes

org.apache.dubbo.config.ReferenceConfig and org.apache.dubbo.common.config.ReferenceCache may be defined as non-singleton mode.

Troubleshooting and Resolution Steps

Check custom annotations or configurations that have defined the core application class as non-singleton mode, and check the scope configuration.

5-28 - No available annotations found

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

Possible Causes

No reliable annotations found under the scanned package configuration. Mainly @DubboService or @Service

Troubleshooting and Resolving Steps

Check the current version in use; prior to 2.7.7 it scanned for @Service annotations, and thereafter for @DubboService

5-29 - Scan package not configured

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

Possible Causes

The parameter value of the @EnableDubbo.scanBasePackages annotation is not configured.

Troubleshooting and Resolution Steps

Simply configure @EnableDubbo.scanBasePackages.

5-30 - Duplicate Bean Definition Declaration

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

Possible Causes

The declared object ID or name is duplicated.

Troubleshooting and Resolution Steps

Modify the name to make it unique based on the fully qualified class name output in the console.

5-31 - Status Check Error

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

Possible Causes

The status of the currently running server; the system’s CPU usage is too high or memory and other indicators are too low.

Troubleshooting and Resolution Steps

Check the current memory usage status of the server and the CPU usage along with other indicators. There may be a risk of downtime.

5-32 - Error Occurred When Apollo Disconnected

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

Possible Causes

The Apollo configuration center may be down or the network may be disconnected.

Troubleshooting and Resolution Steps

Check the status of the Apollo server and verify if the network communication is functioning properly.

5-33 - Exception Occurred During Apollo Configuration Update Event

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

Possible Causes

Incorrect usage of Apollo Configuration API.

Troubleshooting and Resolution Steps

Please refer to the documentation on the dynamic configuration center regarding the Apollo section.

5-34 - Error Occurred in NACOS

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

Possible Causes

Incorrect use of the NACOS configuration API.

Troubleshooting and Resolution Steps

Please refer to the description of the NACOS section in the dynamic configuration center usage documentation.

5-35 - Container initialization failure

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

Possible Causes

Undefined interface org.apache.dubbo.container.Container SPI implementation.

Note: Currently tested in the org.apache.dubbo.container.Main class.

Troubleshooting and Resolution Steps

5-36 - Error occurred during filter validation

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

Possible Causes

An exception occurs in the business code within the overridden invoke method of the custom filter extension class.

Troubleshooting and Solutions

Use ps -eaf |grep <error service>
You can analyze the stack trace using some third-party tools or by using jstack [PID] > jstack.log for diagnosis.

5-37 - Dynamic configuration listener processing error

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

Listener event handling failed when the file changed

Possible Reasons

File permissions have changed or directory permissions have changed.

Troubleshooting and Resolution Steps

You can locate the code based on the stack information from the console.

5-38 - Configuration parameter undefined

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

Possible Reasons

Configuration parameter undefined

Troubleshooting and Resolution Steps

Mainly used in test cases, configure the parameters according to the prompt details.

5-39 - Error occurred with Dubbo Config Bean Initializer

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

Possible Causes

Source code or modifications made

Troubleshooting and Resolution Steps

Check that the business code hasn’t modified the core classes or the order in which they are loaded. For example: org.apache.dubbo.config.spring.context.DubboConfigBeanInitializer

5-40 - Dubbo configuration bean not found

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

Possible Causes

Source code or modification

Troubleshooting and Resolution Steps

Check that the business code has not modified the source code of core classes or altered the loading order. For example: org.apache.dubbo.config.spring.context.DubboConfigBeanInitializer

5-41 - Failed to Read SSL Certificate

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

Possible Reasons

Abnormal SSL certificate configuration

Troubleshooting and Resolution Steps

Check the SSL certificate configuration and see if the corresponding file exists

5-42 - Dubbo Certificate Issuance Failure

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

Possible Causes

Dubbo failed to request the remote CA to issue a certificate.

Troubleshooting and Resolution Steps

Check CA connection configuration
Check CA operational status
Check CA logs

5-43 - Dubbo certificate issuance connection is insecure

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

Possible Causes

The connection between Dubbo and the remote CA is insecure.

Troubleshooting and Resolution Steps

Check whether the Dubbo process has been correctly configured with the CA certificate information and the method for obtaining the OIDC (OpenID Connect) Token.