这是启动机器上

[root@storm01 data]# zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /export/servers/zookeeper/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[root@storm01 data]# zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /export/servers/zookeeper/bin/../conf/zoo.cfg
Mode: follower
[root@storm01 data]#

以前都可以启动，但是现在有一个台不能启动了

[root@storm1 conf]# zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /export/servers/zookeeper/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[root@storm1 conf]# zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /export/servers/zookeeper/bin/../conf/zoo.cfg
Error contacting service. It is probably not running.

查看日志zookeeper.out日志

java.lang.Exception: shutdown Follower
        at org.apache.zookeeper.server.quorum.Follower.shutdown(Follower.java:164)
        at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:850)
2017-03-29 18:00:31,402 [myid:3] - INFO  [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:FollowerZooKeeperServer@140] - Shutting down
2017-03-29 18:00:31,402 [myid:3] - INFO  [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:QuorumPeer@774] - LOOKING
2017-03-29 18:00:31,402 [myid:3] - INFO  [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:FastLeaderElection@818] - New election. My id =  3, proposed zxid=0xf00000005
2017-03-29 18:00:31,405 [myid:3] - INFO  [WorkerReceiver[myid=3]:FastLeaderElection@600] - Notification: 1 (message format version), 2 (n.leader), 0xf00000005 (n.zxid)

解决方式
提升zoo.cfg配置文件tickTime值，或者initLimit值也可以，这是因为允许followerk连接并同步到leader的初始化连接时间（具体时间tickTime*initLimit），如果超过这个时间就表示失败。
如果不愿意改配置文件，只要在tickTime*initLimit内启动所有机器的zookeeper即可