ZooInspector 鏈接不到 Zookeeper 的解決方法

Zookeeper正常啓動後，在使用 ZooInspector 鏈接 Zookeeper 時出現了鏈接不上的問題。

[root@localhost bin]# zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /usr/local/zookeeper-3.4.11/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED

看打印出的信息是啓動成功了，但就是鏈接不上。

決解方法：

這時查看一下Zookeeper的啓動狀態或日誌文件：

[root@localhost bin]# zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /usr/local/zookeeper-3.4.11/bin/../conf/zoo.cfg
Error contacting service. It is probably not running.

能夠看到發生了錯誤，並無正常啓動。

再看一下日誌文件：

2017-12-13 17:56:37,514 [myid:] - INFO  [main-SendThread(localhost:2181):ClientCnxn$SendThread@1161] - Unable to read additional data from server sessionid 0x100000438d60007, likely server has closed socket, closing socket connection and attempting reconnect
2017-12-13 17:56:37,668 [myid:1] - WARN  [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumPeer$QuorumServer@190] - Failed to resolve address: slave-03
java.net.UnknownHostException: slave-03: 未知的名稱或服務
	at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
	at java.net.InetAddress$2.lookupAllHostAddr(InetAddress.java:928)
	at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1323)
	at java.net.InetAddress.getAllByName0(InetAddress.java:1276)
	at java.net.InetAddress.getAllByName(InetAddress.java:1192)
	at java.net.InetAddress.getAllByName(InetAddress.java:1126)
	at java.net.InetAddress.getByName(InetAddress.java:1076)
	at org.apache.zookeeper.server.quorum.QuorumPeer$QuorumServer.recreateSocketAddresses(QuorumPeer.java:180)
	at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:591)
	at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:610)
	at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:845)
	at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:957)
2017-12-13 17:56:37,669 [myid:1] - INFO  [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:FastLeaderElection@854] - Notification time out: 60000
2017-12-13 17:56:38,277 [myid:] - INFO  [main-SendThread(localhost:2181):ClientCnxn$SendThread@1035] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:2181. Will not attempt to authenticate using SASL (unknown error)

大概猜出來了，配置文件中有錯誤：

[root@localhost bin]# vim ../conf/zoo.cfg 

tickTime=2000
dataDir=/usr/local/zookeeper-3.4.11/data
dataLogDir=/usr/local/zookeeper-3.4.11/log
clientPort=2181
initLimit=5
syncLimit=2
server.1=slave-01:2888:3888
server.2=slave-02:2888:3888
server.3=slave-03:2888:3888

文件中配置的是集羣方式，如今是單機啓動（不是單機啓動不行，而是學習的過程當中實驗環境一直在變化）