1.异常描述

sprang cloud alibaba nacos + dubbo 部署在doker环境，在重启服务后dubbo接口无法使用,报错No provider available for the service

问题环境

pom

 <!-- Spring Boot --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-dependencies</artifactId> <version>2.2.5.RELEASE</version> <type>pom</type> <scope>import</scope> </dependency> <!--spring-cloud版本管理--> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Hoxton.RELEASE</version> <type>pom</type> <scope>import</scope> </dependency> <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-alibaba-dependencies</artifactId> <version>2.2.1.RELEASE</version> <type>pom</type> <scope>import</scope> </dependency>

讯享网

docker 配置

讯享网docker run -d --name orderServer --network=host

2. 异常分析

在服务停止时出现了以下异常

2020-09-17 16:52:04.135 [] [DubboShutdownHook] INFO org.apache.dubbo.registry.nacos.NacosRegistry - [DUBBO] Destroy unsubscribe url consumer://172.18.0.1/com.demo.service.OrderDubboService?application=pay-server&category=providers,configurators,routers&check=false&dubbo=2.0.2&init=false&interface=com.demo.service.OrderDubboService&methods=getOperationLogList,orderSave,getDetail,getTotalNumByParam,infoList,getExportList,list&pid=1&qos.enable=false&release=2.7.6&retries=-1&revision=1.1.0.RELEASE&side=consumer&sticky=false&timestamp=92&version=1.0.0, dubbo version: 2.7.6, current host: 172.18.0.1 Exception in thread "DubboShutdownHook" java.lang.RuntimeException: java.util.ConcurrentModificationException at org.apache.dubbo.common.function.ThrowableAction.execute(ThrowableAction.java:48) at org.apache.dubbo.common.lang.ShutdownHookCallbacks.lambda$callback$0(ShutdownHookCallbacks.java:70) at java.lang.Iterable.forEach(Iterable.java:75) at org.apache.dubbo.common.lang.ShutdownHookCallbacks.callback(ShutdownHookCallbacks.java:70) at org.apache.dubbo.config.DubboShutdownHook.callback(DubboShutdownHook.java:85) at org.apache.dubbo.config.DubboShutdownHook.run(DubboShutdownHook.java:73) Caused by: java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextNode(HashMap.java:1437) at java.util.HashMap$ValueIterator.next(HashMap.java:1466) at java.util.Collections$UnmodifiableCollection$1.next(Collections.java:1042) at org.apache.dubbo.registry.support.AbstractRegistryFactory.destroyAll(AbstractRegistryFactory.java:85) at org.apache.dubbo.config.DubboShutdownHook.destroyAll(DubboShutdownHook.java:128) at org.apache.dubbo.config.bootstrap.DubboBootstrap.destroy(DubboBootstrap.java:1039) at org.apache.dubbo.config.bootstrap.DubboBootstrap$1.callback(DubboBootstrap.java:191) at org.apache.dubbo.common.function.ThrowableAction.exe

判断可能是dubbo服务连接没有正常关闭，导致连接没有断开重启之后出现访问不到的情况

然后就百度了下docker 环境下dubbo 如何优雅的关闭

1，使用

讯享网kill -15

2，在Dockerfile修改java 启动的命令

CMD ["java","-jar","-Duser.timezone=GMT+08","user.jar"]

还是会出现

最后尝试升级dubbo版本

spring-cloud-alibaba由2.2.1.RELEASE升级为2.2.2.RELEASE问题解决

spring-cloud-alibaba内置dubbo版本由2.7.6升级为2.7.8

讯享网 <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-alibaba-dependencies</artifactId> <version>2.2.2.RELEASE</version> <type>pom</type> <scope>import</scope> </dependency>