2018-08-09 05:12:36,104 [myid:1] - WARN  [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@588] - Cannot open channel to 3 at election address server3/124.226.216.249:3881
java.net.ConnectException: Connection refused (Connection refused)
        at java.net.PlainSocketImpl.socketConnect(Native Method)
        at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
        at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
        at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
        at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
        at java.net.Socket.connect(Socket.java:589)
        at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:562)
        at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:614)
        at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:843)
        at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:913)
2018-08-09 05:12:36,104 [myid:1] - INFO  [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumPeer$QuorumServer@167] - Resolved hostname: server3 to address: server3/

这种情况一般是两种：

1 端口的防火墙没开

2 如果是放在云上的话，zoo.cfg里面的ip要是内网地址，不能是别名或者公网地址