[Bug] No such extension org.apache.dubbo.rpc.Protocol by name tri.default

[jockercheng91]

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Apache Dubbo Component

Java SDK (apache/dubbo)

Dubbo Version

Apache dubbo： 3.3.0

Steps to reproduce this issue

only one provider：
@DubboService(registry = "epasregistry")
public class Dubbo3HelloServiceImpl implements HelloService {

@Override
public String sayHello(String name) {
    long l = System.currentTimeMillis();
    System.out.println(l);
    return String.valueOf(l) + "-" + name;
}

}

properties：
dubbo.protocols.dubbo.name=dubbo
dubbo.protocols.dubbo.port=50051
dubbo.protocols.dubbo.dispatcher=message
dubbo.protocols.dubbo.threads=500
dubbo.protocols.dubbo.ext-protocol=tri,
dubbo.protocols.dubbo.serialization=fastjson2
dubbo.protocols.dubbo.payload=20485760

启动报错：

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2025-09-28 17:12:13.948 [main] ERROR o.s.boot.SpringApplication - Application run failed
java.lang.IllegalStateException: No such extension org.apache.dubbo.rpc.Protocol by name tri.default, no related exception was found, please check whether related SPI module is missing.
at org.apache.dubbo.common.extension.ExtensionLoader.findException(ExtensionLoader.java:768)
at org.apache.dubbo.common.extension.ExtensionLoader.createExtension(ExtensionLoader.java:775)
at org.apache.dubbo.common.extension.ExtensionLoader.getExtension(ExtensionLoader.java:575)
at org.apache.dubbo.common.extension.ExtensionLoader.getExtension(ExtensionLoader.java:549)
at org.apache.dubbo.config.ServiceConfig.findConfiguredPort(ServiceConfig.java:1107)
at org.apache.dubbo.config.ServiceConfig.buildUrl(ServiceConfig.java:831)
at org.apache.dubbo.config.ServiceConfig.doExportUrlsFor1Protocol(ServiceConfig.java:615)
at org.apache.dubbo.config.ServiceConfig.doExportUrls(ServiceConfig.java:600)
at org.apache.dubbo.config.ServiceConfig.doExport(ServiceConfig.java:555)
at org.apache.dubbo.config.ServiceConfig.export(ServiceConfig.java:343)
at org.apache.dubbo.config.deploy.DefaultModuleDeployer.exportServiceInternal(DefaultModuleDeployer.java:495)
at org.apache.dubbo.config.deploy.DefaultModuleDeployer.exportServices(DefaultModuleDeployer.java:442)
at org.apache.dubbo.config.deploy.DefaultModuleDeployer.startSync(DefaultModuleDeployer.java:177)
at org.apache.dubbo.config.deploy.DefaultModuleDeployer.start(DefaultModuleDeployer.java:159)
at org.apache.dubbo.config.spring.context.DubboDeployApplicationListener.onContextRefreshedEvent(DubboDeployApplicationListener.java:167)
at org.apache.dubbo.config.spring.context.DubboDeployApplicationListener.onApplicationEvent(DubboDeployApplicationListener.java:153)
at org.apache.dubbo.config.spring.context.DubboDeployApplicationListener.onApplicationEvent(DubboDeployApplicationListener.java:52)
at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:178)
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:171)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:145)
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:429)
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:386)
at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:949)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:594)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:732)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:409)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:308)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1300)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1289)
at com.iflytek.edu.dubbo3.samples.muti.register.CompDubbo3Server.main(CompDubbo3Server.java:17)

Checked all the code, but no tri.default extension protocol was found. In what scenarios would this protocol be used by default? When the service publisher is explicitly specified with @DubboService(registry = "epasregistry", protocol = "dubbo"), it starts normally.

What you expected to happen

Expect normal startup and normal RPC calls.

Anything else

No response

Are you willing to submit a pull request to fix on your own?

• Yes I am willing to submit a pull request on my own!

Code of Conduct

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

[zrlw]

see Dubbo Multiple Protocol Example
https://github.com/apache/dubbo-samples/tree/master/2-advanced/dubbo-samples-multiple-protocols

[zrlw]

if u want enable servlet for triple at springboot3, dubbo-spring-boot-3-autoconfigure should also be added to pom.xml.

[jockercheng91]

What is the difference between the configurations:
dubbo.protocols.dubbo.name=dubbodubbo.protocols.dubbo.port=50052dubbo.protocols.dubbo.dispatcher=messagedubbo.protocols.dubbo.threads=500dubbo.protocols.dubbo.ext-protocol=tri,
and
dubbo.protocol.name=dubbodubbo.protocol.port=50052dubbo.protocol.dispatcher=messagedubbo.protocol.threads=500dubbo.protocol.ext-protocol=tri,
Why does an exception occur when using dubbo.protocols.dubbo.xxx? In the source code（ConfigManager）:
public ProtocolConfig getOrAddProtocol(String idOrName) {Optional protocol = getProtocol(idOrName);if (protocol.isPresent()) {return protocol.get();}
// Avoiding default protocol configuration overriding custom protocol configuration// due to getOrAddProtocol being called when they are not loadedidOrName = idOrName + ".default";protocol = getProtocol(idOrName);if (protocol.isPresent()) {return protocol.get();}
ProtocolConfig protocolConfig = addConfig(new ProtocolConfig(idOrName));
// addProtocol triggers refresh when other protocols exist in the ConfigManager.// so refresh is only done when ProtocolConfig is not refreshed.if (!protocolConfig.isRefreshed()) {protocolConfig.refresh();}return protocolConfig;}
The ".default" suffix was added to resolve conflicts with custom protocols. Why is the native protocol not found then?

[zrlw]

add ``` around your codes to keep the original format.

[zrlw]

The configuration format doesn't matter. Both dubbo.protocols.dubbo.xxx and dubbo.xxx do the same thing.