＆quot“端口8761已经在使用中”。 - 港口实际上是免费的

Question

我正在使用Eureka Discovery Server工作，当我运行应用程序时，我会得到：

2022-05-29 20:37:54.830 ERROR 19252 --- [  restartedMain] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Web server failed to start. Port 8761 was already in use.

Action:

Identify and stop the process that's listening on port 8761 or configure this application to listen on another port.


Process finished with exit code 0

但是，端口实际上是免费的。我检查资源监视器以及通过CMD检查。 我尝试过的其他事情：

• 更改Discovery Server的端口，并且仍然会得到同样的东西。
• 重新启动PC。
• 结束任务与JDK

发现服务器的属性文件如下：

server.port=8761
spring.application.name=discoveryservice

eureka.client.registerWithEureka=false
eureka.client.fetchRegistry=false

eureka.client.serviceUrl.defaultZone = http://localhost:8761/eureka
eureka.instance.prefer-ip-address=true

spring.security.user.name=test
spring.security.user.password=test

使用-debug：运行应用程序：

2022-05-30 19:28:46.410 DEBUG 17276 --- [  restartedMain] o.s.b.d.LoggingFailureAnalysisReporter   : Application failed to start due to an exception

org.springframework.boot.web.server.PortInUseException: Port 8761 is already in use
    at org.springframework.boot.web.server.PortInUseException.lambda$throwIfPortBindingException$0(PortInUseException.java:70) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.web.server.PortInUseException.lambda$ifPortBindingException$1(PortInUseException.java:85) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.web.server.PortInUseException.ifCausedBy(PortInUseException.java:103) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.web.server.PortInUseException.ifPortBindingException(PortInUseException.java:82) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.web.server.PortInUseException.throwIfPortBindingException(PortInUseException.java:69) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.start(TomcatWebServer.java:228) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.web.servlet.context.WebServerStartStopLifecycle.start(WebServerStartStopLifecycle.java:43) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356) ~[spring-context-5.3.19.jar:5.3.19]
    at java.base/java.lang.Iterable.forEach(Iterable.java:75) ~[na:na]
    at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:740) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:415) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1312) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301) ~[spring-boot-2.6.7.jar:2.6.7]
    at com.don.discoveryserver.DiscoveryServerApplication.main(DiscoveryServerApplication.java:12) ~[classes/:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:568) ~[na:na]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.6.7.jar:2.6.7]
Caused by: java.lang.IllegalArgumentException: standardService.connector.startFailed
    at org.apache.catalina.core.StandardService.addConnector(StandardService.java:238) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.addPreviouslyRemovedConnectors(TomcatWebServer.java:282) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.start(TomcatWebServer.java:213) ~[spring-boot-2.6.7.jar:2.6.7]
    ... 21 common frames omitted
Caused by: org.apache.catalina.LifecycleException: Protocol handler start failed
    at org.apache.catalina.connector.Connector.startInternal(Connector.java:1075) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.apache.catalina.core.StandardService.addConnector(StandardService.java:234) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    ... 23 common frames omitted
Caused by: java.net.BindException: Address already in use: bind
    at java.base/sun.nio.ch.Net.bind0(Native Method) ~[na:na]
    at java.base/sun.nio.ch.Net.bind(Net.java:555) ~[na:na]
    at java.base/sun.nio.ch.ServerSocketChannelImpl.netBind(ServerSocketChannelImpl.java:337) ~[na:na]
    at java.base/sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:294) ~[na:na]
    at org.apache.tomcat.util.net.NioEndpoint.initServerSocket(NioEndpoint.java:274) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.apache.tomcat.util.net.NioEndpoint.bind(NioEndpoint.java:229) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.apache.tomcat.util.net.AbstractEndpoint.bindWithCleanup(AbstractEndpoint.java:1227) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.apache.tomcat.util.net.AbstractEndpoint.start(AbstractEndpoint.java:1313) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.apache.coyote.AbstractProtocol.start(AbstractProtocol.java:614) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    at org.apache.catalina.connector.Connector.startInternal(Connector.java:1072) ~[tomcat-embed-core-9.0.62.jar:9.0.62]
    ... 25 common frames omitted

2022-05-30 19:28:46.410 ERROR 17276 --- [  restartedMain] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Web server failed to start. Port 8761 was already in use.

Action:

Identify and stop the process that's listening on port 8761 or configure this application to listen on another port.


Process finished with exit code 0