今天不小心重启了一下zookeeper服务，发现跑的好好的系统神经了。

客户端连接zk，不停的报

2012-11-12 16:41:37,641 [myid:] - INFO  [main-SendThread(192.168.1.102:2181):ClientCnxn$SendThread@849] - Socket connection established to 192.168.1.102/192.168.1.102:2181, initiating session

2012-11-12 16:41:37,642 [myid:] - INFO  [main-SendThread(192.168.1.102:2181):ClientCnxn$SendThread@1085] - Unable to read additional data from server sessionid 0x0, likely server has closed socket, closing socket connection and attempting reconnect

2012-11-12 16:41:39,099 [myid:] - INFO  [main-SendThread(192.168.1.102:2181):ClientCnxn$SendThread@966] - Opening socket connection to server 192.168.1.102/192.168.1.102:2181. Will not attempt to authenticate using SASL (无法定位登录配置)

google百度看好多hbase有相似的错误，但是没有回答。

郁闷中，有查看另外一机器，报

[zk: 192.168.1.101:2181(CONNECTING) 0] 2012-11-12 16:45:29,050 [myid:] - INFO  [main-SendThread(pay.chj360.com:2181):ClientCnxn$SendThread@966] - Opening socket connection to server xxxxxx.chj360.com/192.168.1.101:2181. Will not attempt to authenticate using SASL (无法定位登录配置)

觉得可能是hosts有问题，打开hosts文件，果然有xxxxxx.chj360.com域名的hosts，而zoo.cfg用的是ip，可能是这个问题。把zoo.cfg用域名映射，然后hosts，重启，好了。

反思自己的zk为啥重启就不行了呢，仔细看了一下zoo.cfg,把datadir设置在/tmp，真是该死了，最近看来是晕乎了！