namenode 自动转换为 datanode

在运行bin/hadoop namenode -format,后，输入bin/start-dfs.sh ，启动各节点没的。然后输入jps，显示伪6691 Jps
2341 DataNode
6591 NameNode
2724 TaskTracker
2497 SecondaryNameNode
过一段时间再输入jps，显示结果是
6738 Jps
2341 DataNode
2724 TaskTracker
2497 SecondaryNameNode
到底是什么阿吗？吗？吗？很急。。。。

补充：并且在命令bin/hadoop fs ls /
10/07/13 21:05:39 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 0 time(s).
10/07/13 21:05:40 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 1 time(s).
10/07/13 21:05:41 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 2 time(s).
10/07/13 21:05:42 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 3 time(s).
10/07/13 21:05:43 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 4 time(s).
10/07/13 21:05:44 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 5 time(s).
10/07/13 21:05:45 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 6 time(s).
10/07/13 21:05:46 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 7 time(s).
10/07/13 21:05:47 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 8 time(s).
10/07/13 21:05:48 INFO ipc.Client: Retrying connect to server: namenode02/192.168.2.35:9000. Already tried 9 time(s).
Bad connection to FS. command aborted.

纯属灵异现象，去logs目录下面看看日志说什么吧

是不是slave文件里有namenode机器的主机名或IP地址吗？

然后，可能是namenode启动不成功，但datanode启动成功了

jps是什么东西啊吗？