[hadoop@zui hadoop]$ hadoop namenode -format WARNING: Use of this script to execute namenode is deprecated. WARNING: Attempting to execute replacement "hdfs namenode" instead.
namenode is running as process 18452. Stop it first.
(3.0.3使用 ： hdfs namenode -formate)
[hadoop@zui hadoop]$ stop-dfs.sh Stopping namenodes on [zui] zui: Warning: Permanently added 'zui' (ECDSA) to the list of known hosts. zui: ERROR: Unable to kill 18452 Stopping datanodes localhost: ERROR: Unable to kill 19132 Stopping secondary namenodes [zui] zui: ERROR: Unable to kill 19311
[hadoop@zui hadoop]$ stop-all.sh WARNING: Stopping all Apache Hadoop daemons as hadoop in 10 seconds. WARNING: Use CTRL-C to abort. Stopping namenodes on [zui] zui: ERROR: Unable to kill 18452 Stopping datanodes localhost: ERROR: Unable to kill 19132 Stopping secondary namenodes [zui] zui: ERROR: Unable to kill 19311 Stopping nodemanagers Stopping resourcemanager
[hadoop@zui hadoop]$ hdfs namenode -format namenode is running as process 18452. Stop it first. [hadoop@zui hadoop]$ kill -9 18452 bash: kill: (18452) - No such process [hadoop@zui hadoop]$ sudo kill -9 18452 [sudo] password for hadoop: hadoop is not in the sudoers file. This incident will be reported.
(使用root kill 进程)
[hadoop@zui hadoop]$** su root** Password: [root@zui hadoop]# kill -9 18452 bash: kill: (18452) - No such process [root@zui hadoop]# sudo kill -9 18452 kill: sending signal to 18452 failed: No such process [root@zui hadoop]#
（该进程是否只有在hadoop同户下才可以查到，但是hadoop使用也显示没有这个进程，**加上sudo提示hadoop not in the sudoers file **)
添加hadoop到 sudoers ： 例子：引用来自 ： https://www.cnblogs.com/dingtian/p/7771046.html
切换用户至root vim /etc/sudoers
找到root ALL=(ALL) ALL，在下方新增
stack ALL=(ALL) NOPASSWD: ALL
wq!
强制保存并退出即可
（过程中发现root没有 sudoers的修改权限， chmod 720 sudoers ---》 ok )
hadoop 有 sudo的权限后，再次kill namenode 进程 ：依然显示没有这个进程 [hadoop@zui etc]$** sudo kill -9 18452** kill: sending signal to 18452 failed: No such process （可是我日勒个去，执行hdfs namenode -format时候就是显示namenode is running 18452）
我fuck了自己，rm了 3.0.3,接下来使用2.6.0
