zookeeper：配置的集群信息是domain：端口2888：端口3888； domain为内网静态ip；每次启动都不能相互连接报错误：
[myid:3] – WARN [WorkerSender[myid=3]:QuorumCnxManager@382] – Cannot open channel to 1 at election address zook1/10.100.20.73:3888
java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:579)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:368)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.toSend(QuorumCnxManager.java:341)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.process(FastLeaderElection.java:449)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.run(FastLeaderElection.java:430)
at java.lang.Thread.run(Thread.java:745)
修改了下：将hosts文件中配置了：外网ip domain； 内网ip domain； 重新启动zookeeper集群，就能正常连接；
诡异的是：我重新删除hosts文件中的配置：外网ip domain 删除， 然后重启zookeeper集群，竟然能正常连接。。。。
汗颜！！！！！！！！！！！！！！！！！！我测试了几遍 诡异诡异？？啥原因呢?部署了两套zookeeper集群都是这现象！！
/etc/hosts文件配置后，不是立马生效么？？？？？？？？？？？？？？？？？？？