Issue 1:
Dubbo version: master

JDK version: 1.8

Reproduce

SPI config file:

META-INF/dubbo/internal/com.limore.ExtensionConflict

impl1=com.limore.impl.ExtensionConflictImpl1

META-INF/dubbo/com.limore.ExtensionConflict

impl1=com.limore.impl.ExtensionConflictImpl2

Note: the SPI file in different directory

then use ExtensionLoader load ExtensionConflict

ExtensionLoader.getExtensionLoader(ExtensionConflict.class).getExtension("impl1") // return ExtensionConflictImpl1

result: no exception occured, ExtensionConflictImpl2 loaded by class loader, but returned ExtensionConflictImpl1

Expectation: throw 'Duplicate extension' exception

The Reason

ExtensionLoader#L764 throw 'duplicate extension' exception, and ExtensionLoader#LL706 collect the exception, but there is no any code process the collected exceptions. reference ExtensionLoader#L661 and ExtensionLoader#L628 method.

Issue 2:
I have searched the issues of this repository and believe that this is not a duplicate.

I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

Dubbo version: 2.7.1

Operating System version: windows10, zk: ubuntu 18.04

Java version: 1.8

Steps to reproduce this issue

I am following the instruction of README.md and the provider sucessfully reigster to zk but consumer cannot consume properly.

[14/05/19 08:26:04:004 CST] main INFO logger.LoggerFactory: using logger: org.apache.dubbo.common.logger.log4j.Log4jLoggerAdapter
[14/05/19 08:26:05:005 CST] main WARN config.AbstractConfig: [DUBBO] There's no valid metadata config found, if you are using the simplified mode of registry url, please make sure you have a metadata address configured properly., dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:05:005 CST] main INFO utils.Compatibility: Running in ZooKeeper 3.4.x compatibility mode
[14/05/19 08:26:05:005 CST] main INFO imps.CuratorFrameworkImpl: Starting
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:zookeeper.version=3.4.13-2d71af4dbe22557fda74f9a9b4309b15a7487f03, built on 06/29/2018 00:39 GMT
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:host.name=DLCN34609493A.apj.global.corp.sap
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:java.version=1.8.0_201
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:java.vendor=Oracle Corporation
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:java.home=C:\Program Files\Java\jdk1.8.0_201\jre
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:java.class.path=C:\Program Files\Java\jdk1.8.0_201\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\rt.jar;C:\Users\I508530\Desktop\Git\dubbo_jcorn\target\classes;C:\Users\I508530\.m2\repository\org\apache\dubbo\dubbo\2.7.1\dubbo-2.7.1.jar;C:\Users\I508530\.m2\repository\org\springframework\spring-context\4.3.16.RELEASE\spring-context-4.3.16.RELEASE.jar;C:\Users\I508530\.m2\repository\org\springframework\spring-aop\4.3.16.RELEASE\spring-aop-4.3.16.RELEASE.jar;C:\Users\I508530\.m2\repository\org\springframework\spring-beans\4.3.16.RELEASE\spring-beans-4.3.16.RELEASE.jar;C:\Users\I508530\.m2\repository\org\springframework\spring-core\4.3.16.RELEASE\spring-core-4.3.16.RELEASE.jar;C:\Users\I508530\.m2\repository\commons-logging\commons-logging\1.2\commons-logging-1.2.jar;C:\Users\I508530\.m2\repository\org\springframework\spring-expression\4.3.16.RELEASE\spring-expression-4.3.16.RELEASE.jar;C:\Users\I508530\.m2\repository\org\javassist\javassist\3.20.0-GA\javassist-3.20.0-GA.jar;C:\Users\I508530\.m2\repository\io\netty\netty-all\4.1.25.Final\netty-all-4.1.25.Final.jar;C:\Users\I508530\.m2\repository\com\google\code\gson\gson\2.8.5\gson-2.8.5.jar;C:\Users\I508530\.m2\repository\org\yaml\snakeyaml\1.20\snakeyaml-1.20.jar;C:\Users\I508530\.m2\repository\org\apache\curator\curator-recipes\4.0.1\curator-recipes-4.0.1.jar;C:\Users\I508530\.m2\repository\org\apache\curator\curator-framework\4.0.1\curator-framework-4.0.1.jar;C:\Users\I508530\.m2\repository\org\apache\curator\curator-client\4.0.1\curator-client-4.0.1.jar;C:\Users\I508530\.m2\repository\com\google\guava\guava\20.0\guava-20.0.jar;C:\Users\I508530\.m2\repository\org\apache\zookeeper\zookeeper\3.4.13\zookeeper-3.4.13.jar;C:\Users\I508530\.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\I508530\.m2\repository\org\slf4j\slf4j-log4j12\1.7.25\slf4j-log4j12-1.7.25.jar;C:\Users\I508530\.m2\repository\log4j\log4j\1.2.16\log4j-1.2.16.jar;C:\Users\I508530\.m2\repository\jline\jline\0.9.94\jline-0.9.94.jar;C:\Users\I508530\.m2\repository\org\apache\yetus\audience-annotations\0.5.0\audience-annotations-0.5.0.jar;C:\Users\I508530\AppData\Local\JetBrains\Toolbox\apps\IDEA-U\ch-0\183.5912.21\lib\idea_rt.jar
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:java.library.path=C:\Program Files\Java\jdk1.8.0_201\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\Program Files\Java\jdk1.8.0_201\bin;C:\Program Files\Java\jdk1.8.0_201\jre\bin;C:\ProgramData\chocolatey\bin;C:\Program Files\Git\bin;C:\Users\I508530\Desktop\protoc\bin;C:\Users\I508530\AppData\Local\Microsoft\WindowsApps;;C:\Users\I508530\AppData\Local\Programs\Microsoft VS Code\bin;.
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:java.io.tmpdir=C:\Users\I508530\AppData\Local\Temp\
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:java.compiler=<NA>
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:os.name=Windows 10
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:os.arch=amd64
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:os.version=10.0
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:user.name=I508530
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:user.home=C:\Users\I508530
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Client environment:user.dir=C:\Users\I508530\Desktop\Git\dubbo_jcorn
[14/05/19 08:26:05:005 CST] main INFO zookeeper.ZooKeeper: Initiating client connection, connectString=114.116.164.43:2181 sessionTimeout=60000 watcher=org.apache.curator.ConnectionState@3ec300f1
[14/05/19 08:26:06:006 CST] main-SendThread(ecs-114-116-164-43.compute.hwclouds-dns.com:2181) INFO zookeeper.ClientCnxn: Opening socket connection to server ecs-114-116-164-43.compute.hwclouds-dns.com/114.116.164.43:2181. Will not attempt to authenticate using SASL (unknown error)
[14/05/19 08:26:06:006 CST] main INFO imps.CuratorFrameworkImpl: Default schema
[14/05/19 08:26:06:006 CST] main INFO zookeeper.ZookeeperTransporter: [DUBBO] No valid zookeeper client found from cache, therefore create a new client for url. zookeeper://114.116.164.43:2181/ConfigCenterConfig?address=zookeeper://114.116.164.43:2181&check=true&configFile=dubbo.properties&group=dubbo&highestPriority=false&namespace=dubbo&prefix=dubbo.config-center&timeout=3000&valid=true, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:06:006 CST] main-SendThread(ecs-114-116-164-43.compute.hwclouds-dns.com:2181) INFO zookeeper.ClientCnxn: Socket connection established to ecs-114-116-164-43.compute.hwclouds-dns.com/114.116.164.43:2181, initiating session
[14/05/19 08:26:06:006 CST] main-SendThread(ecs-114-116-164-43.compute.hwclouds-dns.com:2181) INFO zookeeper.ClientCnxn: Session establishment complete on server ecs-114-116-164-43.compute.hwclouds-dns.com/114.116.164.43:2181, sessionid = 0x1016cfd22560023, negotiated timeout = 40000
[14/05/19 08:26:06:006 CST] main-EventThread INFO state.ConnectionStateManager: State change: CONNECTED
[14/05/19 08:26:06:006 CST] main WARN config.ConfigurationUtils: [DUBBO] You specified the config centre, but there's not even one single config item in it., dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:06:006 CST] main WARN config.ConfigurationUtils: [DUBBO] You specified the config centre, but there's not even one single config item in it., dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:06:006 CST] main INFO config.AbstractConfig: [DUBBO] There's no valid monitor config found, if you want to open monitor statistics for Dubbo, please make sure your monitor is configured properly., dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:06:006 CST] main ERROR server.Server: [DUBBO] qos-server can not bind localhost:22222, dubbo version: 2.7.1, current host: 172.30.158.141
java.net.BindException: Address already in use: bind
at sun.nio.ch.Net.bind0(Native Method)
at sun.nio.ch.Net.bind(Net.java:433)
at sun.nio.ch.Net.bind(Net.java:425)
at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:223)
at io.netty.channel.socket.nio.NioServerSocketChannel.doBind(NioServerSocketChannel.java:128)
at io.netty.channel.AbstractChannel$AbstractUnsafe.bind(AbstractChannel.java:558)
at io.netty.channel.DefaultChannelPipeline$HeadContext.bind(DefaultChannelPipeline.java:1358)
at io.netty.channel.AbstractChannelHandlerContext.invokeBind(AbstractChannelHandlerContext.java:501)
at io.netty.channel.AbstractChannelHandlerContext.bind(AbstractChannelHandlerContext.java:486)
at io.netty.channel.DefaultChannelPipeline.bind(DefaultChannelPipeline.java:1019)
at io.netty.channel.AbstractChannel.bind(AbstractChannel.java:254)
at io.netty.bootstrap.AbstractBootstrap$2.run(AbstractBootstrap.java:366)
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:404)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:465)
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:884)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.lang.Thread.run(Thread.java:748)
[14/05/19 08:26:06:006 CST] main WARN protocol.QosProtocolWrapper: [DUBBO] Fail to start qos server: , dubbo version: 2.7.1, current host: 172.30.158.141
java.net.BindException: Address already in use: bind
at sun.nio.ch.Net.bind0(Native Method)
at sun.nio.ch.Net.bind(Net.java:433)
at sun.nio.ch.Net.bind(Net.java:425)
at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:223)
at io.netty.channel.socket.nio.NioServerSocketChannel.doBind(NioServerSocketChannel.java:128)
at io.netty.channel.AbstractChannel$AbstractUnsafe.bind(AbstractChannel.java:558)
at io.netty.channel.DefaultChannelPipeline$HeadContext.bind(DefaultChannelPipeline.java:1358)
at io.netty.channel.AbstractChannelHandlerContext.invokeBind(AbstractChannelHandlerContext.java:501)
at io.netty.channel.AbstractChannelHandlerContext.bind(AbstractChannelHandlerContext.java:486)
at io.netty.channel.DefaultChannelPipeline.bind(DefaultChannelPipeline.java:1019)
at io.netty.channel.AbstractChannel.bind(AbstractChannel.java:254)
at io.netty.bootstrap.AbstractBootstrap$2.run(AbstractBootstrap.java:366)
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:404)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:465)
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:884)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.lang.Thread.run(Thread.java:748)
[14/05/19 08:26:06:006 CST] main INFO zookeeper.ZookeeperRegistry: [DUBBO] Load registry cache file C:\Users\I508530\.dubbo\dubbo-registry-first-dubbo-consumer-114.116.164.43:2181.cache, data: {cn.jcorn.dubbo.api.GreetingService=empty://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=routers&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=15580&release=2.7.1&side=consumer&sticky=false&timestamp=1557836659355 empty://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=configurators&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=15580&release=2.7.1&side=consumer&sticky=false&timestamp=1557836659355 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=17480&register=true&release=2.7.1&side=provider&timestamp=1557834311569 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=14608&register=true&release=2.7.1&side=provider&timestamp=1557830137270 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=14616&register=true&release=2.7.1&side=provider&timestamp=1557830522802 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=demo-provider&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=20900&register=true&release=2.7.1&side=provider&timestamp=1557836234121 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=demo-provider&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=24724&register=true&release=2.7.1&side=provider&timestamp=1557835560283 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=5976&register=true&release=2.7.1&side=provider&timestamp=1557830110613 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=5972&register=true&release=2.7.1&side=provider&timestamp=1557830616062 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=21724&register=true&release=2.7.1&side=provider&timestamp=1557836633787 dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=demo-provider&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=3056&register=true&release=2.7.1&side=provider&timestamp=1557835269408}, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:06:006 CST] main INFO zookeeper.ZookeeperTransporter: [DUBBO] find valid zookeeper client from the cache for address: zookeeper://114.116.164.43:2181/org.apache.dubbo.registry.RegistryService?application=first-dubbo-consumer&dubbo=2.0.2&interface=org.apache.dubbo.registry.RegistryService&pid=11864&release=2.7.1&timestamp=1557836766196, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:06:006 CST] main INFO zookeeper.ZookeeperRegistry: [DUBBO] Register: consumer://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=consumers&check=false&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:06:006 CST] main INFO zookeeper.ZookeeperRegistry: [DUBBO] Subscribe: consumer://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=providers,configurators,routers&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:07:007 CST] main INFO zookeeper.ZookeeperRegistry: [DUBBO] Notify urls for subscribe url consumer://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=providers,configurators,routers&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, urls: [dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=17480&register=true&release=2.7.1&side=provider&timestamp=1557834311569, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=14608&register=true&release=2.7.1&side=provider&timestamp=1557830137270, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=14616&register=true&release=2.7.1&side=provider&timestamp=1557830522802, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=demo-provider&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=20900&register=true&release=2.7.1&side=provider&timestamp=1557836234121, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=demo-provider&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=24724&register=true&release=2.7.1&side=provider&timestamp=1557835560283, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=5976&register=true&release=2.7.1&side=provider&timestamp=1557830110613, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=5972&register=true&release=2.7.1&side=provider&timestamp=1557830616062, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-provider&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=21724&register=true&release=2.7.1&side=provider&timestamp=1557836633787, dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=demo-provider&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&default.deprecated=false&default.dynamic=false&default.register=true&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&methods=sayHello&pid=3056&register=true&release=2.7.1&side=provider&timestamp=1557835269408, empty://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=configurators&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, empty://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=routers&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532], dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] main WARN transport.AbstractClient: [DUBBO] Failed to start NettyClient DLCN34609493A/172.30.158.141 connect to the server /172.30.158.141:20880 (check == false, ignore and retry later!), cause: client(url: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&codec=dubbo&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&heartbeat=60000&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557834311569&side=consumer&sticky=false&timestamp=1557836765532) failed to connect to server /172.30.158.141:20880 client-side timeout 3000ms (elapsed: 3005ms) from netty client 172.30.158.141 using dubbo version 2.7.1, dubbo version: 2.7.1, current host: 172.30.158.141
org.apache.dubbo.remoting.RemotingException: client(url: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&codec=dubbo&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&heartbeat=60000&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557834311569&side=consumer&sticky=false&timestamp=1557836765532) failed to connect to server /172.30.158.141:20880 client-side timeout 3000ms (elapsed: 3005ms) from netty client 172.30.158.141 using dubbo version 2.7.1
at org.apache.dubbo.remoting.transport.netty4.NettyClient.doConnect(NettyClient.java:136)
at org.apache.dubbo.remoting.transport.AbstractClient.connect(AbstractClient.java:186)
at org.apache.dubbo.remoting.transport.AbstractClient.<init>(AbstractClient.java:65)
at org.apache.dubbo.remoting.transport.netty4.NettyClient.<init>(NettyClient.java:57)
at org.apache.dubbo.remoting.transport.netty4.NettyTransporter.connect(NettyTransporter.java:37)
at org.apache.dubbo.remoting.Transporter$Adaptive.connect(Transporter$Adaptive.java)
at org.apache.dubbo.remoting.Transporters.connect(Transporters.java:75)
at org.apache.dubbo.remoting.exchange.support.header.HeaderExchanger.connect(HeaderExchanger.java:39)
at org.apache.dubbo.remoting.exchange.Exchangers.connect(Exchangers.java:109)
at org.apache.dubbo.rpc.protocol.dubbo.DubboProtocol.initClient(DubboProtocol.java:577)
at org.apache.dubbo.rpc.protocol.dubbo.DubboProtocol.buildReferenceCountExchangeClient(DubboProtocol.java:545)
at org.apache.dubbo.rpc.protocol.dubbo.DubboProtocol.buildReferenceCountExchangeClientList(DubboProtocol.java:532)
at org.apache.dubbo.rpc.protocol.dubbo.DubboProtocol.getSharedClient(DubboProtocol.java:457)
at org.apache.dubbo.rpc.protocol.dubbo.DubboProtocol.getClients(DubboProtocol.java:412)
at org.apache.dubbo.rpc.protocol.dubbo.DubboProtocol.refer(DubboProtocol.java:389)
at org.apache.dubbo.rpc.protocol.ProtocolListenerWrapper.refer(ProtocolListenerWrapper.java:67)
at org.apache.dubbo.rpc.protocol.ProtocolFilterWrapper.refer(ProtocolFilterWrapper.java:116)
at org.apache.dubbo.qos.protocol.QosProtocolWrapper.refer(QosProtocolWrapper.java:72)
at org.apache.dubbo.rpc.Protocol$Adaptive.refer(Protocol$Adaptive.java)
at org.apache.dubbo.registry.integration.RegistryDirectory.toInvokers(RegistryDirectory.java:408)
at org.apache.dubbo.registry.integration.RegistryDirectory.refreshInvoker(RegistryDirectory.java:265)
at org.apache.dubbo.registry.integration.RegistryDirectory.refreshOverrideAndInvoker(RegistryDirectory.java:224)
at org.apache.dubbo.registry.integration.RegistryDirectory.notify(RegistryDirectory.java:218)
at org.apache.dubbo.registry.support.AbstractRegistry.notify(AbstractRegistry.java:399)
at org.apache.dubbo.registry.support.FailbackRegistry.doNotify(FailbackRegistry.java:364)
at org.apache.dubbo.registry.support.FailbackRegistry.notify(FailbackRegistry.java:355)
at org.apache.dubbo.registry.zookeeper.ZookeeperRegistry.doSubscribe(ZookeeperRegistry.java:169)
at org.apache.dubbo.registry.support.FailbackRegistry.subscribe(FailbackRegistry.java:290)
at org.apache.dubbo.registry.integration.RegistryDirectory.subscribe(RegistryDirectory.java:157)
at org.apache.dubbo.registry.integration.RegistryProtocol.doRefer(RegistryProtocol.java:386)
at org.apache.dubbo.registry.integration.RegistryProtocol.refer(RegistryProtocol.java:367)
at org.apache.dubbo.rpc.protocol.ProtocolListenerWrapper.refer(ProtocolListenerWrapper.java:65)
at org.apache.dubbo.rpc.protocol.ProtocolFilterWrapper.refer(ProtocolFilterWrapper.java:114)
at org.apache.dubbo.qos.protocol.QosProtocolWrapper.refer(QosProtocolWrapper.java:70)
at org.apache.dubbo.rpc.Protocol$Adaptive.refer(Protocol$Adaptive.java)
at org.apache.dubbo.config.ReferenceConfig.createProxy(ReferenceConfig.java:366)
at org.apache.dubbo.config.ReferenceConfig.init(ReferenceConfig.java:305)
at org.apache.dubbo.config.ReferenceConfig.get(ReferenceConfig.java:231)
at cn.jcorn.dubbo.consumer.Application.main(Application.java:15)
Exception in thread "main" java.lang.IllegalStateException: Failed to check the status of the service cn.jcorn.dubbo.api.GreetingService. No provider available for the service cn.jcorn.dubbo.api.GreetingService from the url zookeeper://114.116.164.43:2181/org.apache.dubbo.registry.RegistryService?anyhost=true&application=first-dubbo-consumer&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557834311569&side=consumer&sticky=false&timestamp=1557836765532 to the consumer 172.30.158.141 use dubbo version 2.7.1
at org.apache.dubbo.config.ReferenceConfig.createProxy(ReferenceConfig.java:390)
at org.apache.dubbo.config.ReferenceConfig.init(ReferenceConfig.java:305)
at org.apache.dubbo.config.ReferenceConfig.get(ReferenceConfig.java:231)
at cn.jcorn.dubbo.consumer.Application.main(Application.java:15)
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO config.DubboShutdownHook: [DUBBO] Run shutdown hook now., dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO support.AbstractRegistryFactory: [DUBBO] Close all registries [zookeeper://114.116.164.43:2181/org.apache.dubbo.registry.RegistryService?application=first-dubbo-consumer&dubbo=2.0.2&interface=org.apache.dubbo.registry.RegistryService&pid=11864&release=2.7.1&timestamp=1557836766196], dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO zookeeper.ZookeeperRegistry: [DUBBO] Destroy registry:zookeeper://114.116.164.43:2181/org.apache.dubbo.registry.RegistryService?application=first-dubbo-consumer&dubbo=2.0.2&interface=org.apache.dubbo.registry.RegistryService&pid=11864&release=2.7.1&timestamp=1557836766196, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO zookeeper.ZookeeperRegistry: [DUBBO] Unregister: consumer://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=consumers&check=false&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO zookeeper.ZookeeperRegistry: [DUBBO] Destroy unregister url consumer://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=consumers&check=false&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO zookeeper.ZookeeperRegistry: [DUBBO] Unsubscribe: consumer://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=providers,configurators,routers&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO zookeeper.ZookeeperRegistry: [DUBBO] Destroy unsubscribe url consumer://172.30.158.141/cn.jcorn.dubbo.api.GreetingService?application=first-dubbo-consumer&category=providers,configurators,routers&default.lazy=false&default.sticky=false&dubbo=2.0.2&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&release=2.7.1&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] Curator-Framework-0 INFO imps.CuratorFrameworkImpl: backgroundOperationsLoop exiting
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO zookeeper.ZooKeeper: Session: 0x1016cfd22560023 closed
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Close dubbo connect: 172.30.158.141:0-->/172.30.158.141:20880, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557830522802&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=demo-provider&remote.timestamp=1557835269408&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557830137270&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557830616062&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557830110613&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] main-EventThread INFO zookeeper.ClientCnxn: EventThread shut down for session: 0x1016cfd22560023
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557834311569&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=first-dubbo-provider&remote.timestamp=1557836633787&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=demo-provider&remote.timestamp=1557836234121&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO dubbo.DubboProtocol: [DUBBO] Destroy reference: dubbo://172.30.158.141:20880/cn.jcorn.dubbo.api.GreetingService?anyhost=true&application=first-dubbo-consumer&bean.name=providers:dubbo:cn.jcorn.dubbo.api.GreetingService&check=false&default.deprecated=false&default.dynamic=false&default.lazy=false&default.register=true&default.sticky=false&deprecated=false&dubbo=2.0.2&dynamic=false&generic=false&interface=cn.jcorn.dubbo.api.GreetingService&lazy=false&methods=sayHello&pid=11864&register=true&register.ip=172.30.158.141&release=2.7.1&remote.application=demo-provider&remote.timestamp=1557835560283&side=consumer&sticky=false&timestamp=1557836765532, dubbo version: 2.7.1, current host: 172.30.158.141
[14/05/19 08:26:10:010 CST] DubboShutdownHook INFO server.Server: [DUBBO] qos-server stopped., dubbo version: 2.7.1, current host: 172.30.158.141

and https://github.com/apache/incubator-dubbo-samples/tree/master/dubbo-samples-zookeeper leads to the same result.

dubbo appear to another address, no matter which zk instance I use, there is always a host at 172.30.158.141. but in my properties there is 127.0.0.1 or other ip address.

At dubbo admin there provider registered but consumer appears then soon disappear.

Like apache/dubbo-admin#376 , probider has never disappear but no consumer.