linux下，zookeeper安裝並啟動起來了，
將log4j.properties放在工程的classpath下，然后啟動工程，發現控制台報錯：
2017-03-02 19:52:32,270 INFO [org.apache.zookeeper.ZooKeeper] - Initiating client connection, connectString=192.168.153.128:2181 sessionTimeout=30000 watcher=org.I0Itec.zkclient.ZkClient@1d6ba2b
2017-03-02 19:52:32,288 INFO [org.apache.zookeeper.ClientCnxn] - Opening socket connection to server 192.168.153.128/192.168.153.128:2181. Will not attempt to authenticate using SASL (unknown error)
2017-03-02 19:52:53,291 WARN [org.apache.zookeeper.ClientCnxn] - Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect
java.net.ConnectException: Connection timed out: no further information
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:739)
at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:361)
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1081)
2017-03-02 19:52:54,394 INFO [org.apache.zookeeper.ClientCnxn] - Opening socket connection to server 192.168.153.128/192.168.153.128:2181. Will not attempt to authenticate using SASL (unknown error)
經檢查，是linux下防火牆未關閉，使用一下命令關閉防火牆:
service iptables stop
查看防火牆狀態：
service iptables status
參考資料：https://www.cnblogs.com/hfultrastrong/p/7876198.html