Issue 1:
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: 2.7.6

Java version: JDK8

DUBBO客户端与服务端建立连接超时，然后抛出异常。请问是否可以添加上重试的特性？

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: 2.7.3

Operating System version: win10

Java version: 1.8

SpringBootVersion: 2.0.6 2.0.9

nacos server: 1.1.3

AlibabaCloudStarterNacosDiscovery: 2.0.0

Steps to reproduce this issue

boostrap.yml

spring:
application:
name: demo-banana
cloud:
nacos:
discovery:
server-addr: 127.0.0.1:8848
namespace: 8e135e43-4e66-462b-9039-300f6f8f55c2
config:
server-addr: 127.0.0.1:8848

application.yaml

server:
port: 8200
management:
endpoints:
web:
exposure:
include: "*"

dubbo.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://dubbo.apache.org/schema/dubbo
http://dubbo.apache.org/schema/dubbo/dubbo.xsd">

<!-- 提供方应用信息，用于计算依赖关系 -->
<dubbo:application name="${spring.application.name}" logger="slf4j"/>
<dubbo:config-center address="nacos://127.0.0.1:8848" namespace="public" config-file="dubbo.properties" group="DEFAULT_GROUP"/>
<!-- <dubbo:registry address="nacos://127.0.0.1:8848"/>-->
<dubbo:reference interface="com.example.apple.export.AppleExport" lazy="true" />
</beans>

4.dubbo.properties

dubbo.registry.address=nacos://127.0.0.1:8848

Pls. provide [GitHub address] to reproduce this issue.

Expected Result

启动成功

Actual Result

启动失败

If there is an exception, please attach the exception trace:

[2019-08-16 08:39:37.717] INFO org.apache.catalina.core.AprLifecycleListener : The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: [D:\SDK\JDK8\bin;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;D:\Developer\Jetbrains\IntelliJ IDEA\jbr\\bin;D:\Developer\Jetbrains\IntelliJ IDEA\jbr\\bin\server;C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\Program Files (x86)\Intel\Intel(R) Management Engine Components\iCLS\;C:\Program Files\Intel\Intel(R) Management Engine Components\iCLS\;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Windows\System32\OpenSSH\;C:\Program Files (x86)\Intel\Intel(R) Management Engine Components\DAL;C:\Program Files\Intel\Intel(R) Management Engine Components\DAL;D:\SDK\JDK8\bin;D:\SDK\Python3;C:\Users\xiaolei.fu\AppData\Local\Microsoft\WindowsApps;D:\Common\BandZip\;D:\Developer\Microsoft VS Code\bin;D:\Developer\Jetbrains\IntelliJ IDEA\bin;;.]
[2019-08-16 08:39:37.821] INFO org.apache.catalina.core.ContainerBase.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
[2019-08-16 08:39:37.834] INFO com.alibaba.cloud.sentinel.SentinelWebAutoConfiguration : [Sentinel Starter] register Sentinel CommonFilter with urlPatterns: [/*].
[2019-08-16 08:39:38.510] INFO com.alibaba.nacos.client.naming : initializer namespace from System Property :null
[2019-08-16 08:39:38.510] INFO com.alibaba.nacos.client.naming : initializer namespace from System Environment :null
[2019-08-16 08:39:38.510] INFO com.alibaba.nacos.client.naming : initializer namespace from System Property :null
[2019-08-16 08:39:38.516] DEBUG com.alibaba.nacos.client.naming : failover switch is not found, failover00-00---000-VIPSRV_FAILOVER_SWITCH-000---00-00
[2019-08-16 08:39:38.796] INFO org.apache.catalina.core.StandardService : Stopping service [Tomcat]
[2019-08-16 08:39:38.801] WARN org.apache.catalina.loader.WebappClassLoaderBase : The web application [ROOT] appears to have started a thread named [com.alibaba.nacos.naming.client.listener] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
sun.misc.Unsafe.park(Native Method)
java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
java.util.concurrent.LinkedBlockingQueue.poll(LinkedBlockingQueue.java:467)
com.alibaba.nacos.client.naming.core.EventDispatcher$Notifier.run(EventDispatcher.java:114)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
java.lang.Thread.run(Thread.java:748)