Question

我在linux上装单点hadoop，最后在./start-all.sh之后出现了一下代码，谁能解释一下，这是什么意思？

This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
14/07/14 11:24:25 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Starting namenodes on [localhost]
localhost: namenode running as process 6357. Stop it first.
localhost: starting datanode, logging to /home/hadoop/hadoop-2.4.0/logs/hadoop-root-datanode-master.hadoop.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: secondarynamenode running as process 6637. Stop it first.
14/07/14 11:24:38 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
starting yarn daemons
resourcemanager running as process 6777. Stop it first.
localhost: nodemanager running as process 6880. Stop it first.

Answer 1

start-all.sh这个命令不用了，现在使用start-dfs.sh 和 start-yarn.sh代替start-all.sh命令，可能是因为跟spark里的start-all.sh命令重名了，这是打印的第一行信息的意思；

后面提示的WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable是缺少一个java类库，不影响运行

要解决可以参考

网页链接 里面有解决方法

localhost: namenode running as process 6357. Stop it first.

0.0.0.0: secondarynamenode running as process 6637. 

Stop it first.starting yarn daemons

resourcemanager running as process 6777. Stop it first.
localhost: nodemanager running as process 6880. Stop it first.

这些都是因为你之前已经开启了这些服务，正在运行，你再开启就提示你先关闭

Answer 2

先用jps查看是否有hadoop的线程在运行。
如果有相应的hadoop进程运行，需要你先关闭。

Answer 3

进程已经在运行中了，先执行stop-all.sh下，然后再执行start-all.sh，再不行就把那些进程全部Kill掉再试