Running dubbo-samples

[LI123456mo]

Pre-check

• I am sure that all the content I provide is in English.

Apache Dubbo Component

Java SDK (apache/dubbo)

Details

Dubbo samples (2advanced -> tripple) refuses to run on my locals

The errors:

09:58:39.344 |-ERROR [main] g.springframework.boot.SpringApplication:851 -| Application run failed
java.lang.IllegalStateException: Failed to create nacos config service client. Reason: server status check failed.

09:58:39.291 |-ERROR [main] .support.nacos.NacosDynamicConfiguration: -| [DUBBO] Failed to create nacos config service client. Reason: server status check failed., dubbo version: 3.3.6, current host: 172.19.240.1, error code: 5-34. This may be caused by , go to https://dubbo.apache.org/faq/5/34 to find instructions.

09:58:29.061 |-ERROR [main] com.alibaba.nacos.common.remote.client:102 -| Send request fail, request = ConfigQueryRequest{headers={charset=UTF-8, Client-AppName=unknown, Client-RequestToken=c40520999c61e89c2f7eddb4c15c8e79, Client-RequestTS=1774421908738, exConfigInfo=true, notify=false}, requestId='null'}, retryTimes = 2, errorMessage = Client not connected, current status:STARTING

9:58:29.065 |-ERROR [com.alibaba.nacos.client.remote.worker.1] cos.common.remote.client.grpc.GrpcClient:102 -| Server check fail, please check server 127.0.0.1 ,port 9848 is available , error =java.util.concurrent.ExecutionException: com.alibaba.nacos.shaded.io.grpc.StatusRuntimeException: UNAVAILABLE: io exception
09:58:29.065 |-INFO [com.alibaba.nacos.client.remote.worker.1] com.alibaba.nacos.common.remote.client:63 -| [1e195d6b-5fb1-4e6f-a4f7-769148e82c46_config-0] Fail to connect server, after trying 2 times, last try server is {serverIp = '127.0.0.1', server main port = 8848}, error = unknown

Code of Conduct

• I agree to follow this project's Code of Conduct

[rikhmaier]

This is not a Triple protocol failure. The application is configured to use Nacos, but no reachable Nacos 2.x server is listening at 127.0.0.1:8848/9848.

The key lines are:

Server check fail, please check server 127.0.0.1, port 9848
Client not connected, current status: STARTING

Nacos 2.x uses:

• 8848 for its main HTTP/API port
• 9848 for client gRPC communication
• 9849 for server-to-server gRPC communication

For a local test, start Nacos in standalone mode and expose the required ports:

docker run -d \
  --name nacos-standalone \
  -e MODE=standalone \
  -p 8848:8848 \
  -p 9848:9848 \
  -p 9849:9849 \
  nacos/nacos-server:v2.5.1

Then verify that it is running:

docker ps --filter name=nacos-standalone
curl -fsS http://127.0.0.1:8848/nacos/v1/console/health/liveness

Also verify the gRPC port:

nc -vz 127.0.0.1 9848

If the Dubbo sample itself runs inside Docker, 127.0.0.1 refers to that application container, not the Nacos container. Put both containers on the same Docker network and configure the address using the Nacos service/container name, for example:

dubbo.registry.address=nacos://nacos:8848
dubbo.config-center.address=nacos://nacos:8848
dubbo.metadata-report.address=nacos://nacos:8848

Publishing only port 8848 is insufficient for a Nacos 2.x client; port 9848 must also be reachable. If the configured Nacos main port is changed from 8848, the client gRPC port is calculated as main port + 1000.

If this particular sample is not intended to use Nacos, remove/override its Nacos registry and config-center settings and configure the registry expected by that sample instead. The sample repository recommends reading the individual sample README and starting its required external services before launching it.

Nacos port documentation:
https://www.nacos.io/en/docs/v2.5/upgrading/200-compatibility/

Dubbo samples instructions:
https://github.com/apache/dubbo-samples

[LI123456mo]

Thanks for your feedback