解决Hadoop时no namenode to stop异常或则是 jps中没有namenode

缺乏、安全感 2024-01-20 08:09 56阅读 0赞

### 一：问题: ###

在jps的时候没有发现namenode  
![在这里插入图片描述][20190613093517747.png]  
[在stop-all.sh][stop-all.sh] 的时候 ，出现 No namenode to stop

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNjg4NDcy_size_16_color_FFFFFF_t_70]

### 二：寻找解决方法 ###

1.博客的寻找  
2.在脚本中发现了一个关键的地方

问题关键：就是没有pid文件  
注释：pid是什么文件  
Hadoop启动后，会把进程的PID号存储在一个文件中，这样执行stop-dfs脚本时就可以按照进程PID去关闭进程了。

现在问题原因很明确了，就是/tmp目录下的hadoop-\*.pid的文件找不到了  
这是因为linux会定期30天清理tmp文件  
去tmp目录下面看一下  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNjg4NDcy_size_16_color_FFFFFF_t_70 1]

### 三：解决问题： ###

1.杀死所有进程，一定要清理干净  
2.重新启动hadoop  
3.jps查看  
4.运行一个jop查看，外部界面查看

[hadoop@hadoop001 sbin]$ jps
    18514 Jps
    18196 NodeManager
    17943 SecondaryNameNode
    18093 ResourceManager
    17791 DataNode
    [hadoop@hadoop001 sbin]$ kill -9 18196 17943 18093 17791
    [hadoop@hadoop001 sbin]$ jps
    18533 Jps
    [hadoop@hadoop001 sbin]$ hadoop namenode -format
    
    [hadoop@hadoop001 sbin]$ ./start-all.sh
    This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
    Starting namenodes on [hadoop001]
    hadoop001: starting namenode, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/hadoop-hadoop-namenode-hadoop001.out
    hadoop001: starting datanode, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/hadoop-hadoop-datanode-hadoop001.out
    Starting secondary namenodes [hadoop001]
    hadoop001: starting secondarynamenode, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/hadoop-hadoop-secondarynamenode-hadoop001.out
    starting yarn daemons
    starting resourcemanager, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/yarn-hadoop-resourcemanager-hadoop001.out
    hadoop001: starting nodemanager, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/yarn-hadoop-nodemanager-hadoop001.out
    [hadoop@hadoop001 sbin]$ jps
    19568 Jps
    18832 DataNode
    18705 NameNode
    19250 NodeManager
    18995 SecondaryNameNode
    19146 ResourceManager
    [hadoop@hadoop001 sbin]$ ls /tmp/
    Aegis-<Guid(5A2C30A2-A87D-490A-9281-6765EDAD7CBA)>
    hadoop-hadoop
    hadoop-hadoop-datanode.pid
    hadoop-hadoop-namenode.pid
    hadoop-hadoop-secondarynamenode.pid
    hsperfdata_hadoop
    hsperfdata_root
    Jetty_0_0_0_0_50070_hdfs____w2cu08

### 四：永久不出现这个问题 ###

[hadoop@hadoop002 hadoop-2.6.0-cdh5.7.0]$ vi etc/hadoop/hdaoop_env .sh
    # The directory where pid files are stored. /tmp by default.
    # NOTE: this should be set to a directory that can only be written to by 
    #       the user that will run the hadoop daemons.  Otherwise there is the
    #       potential for a symlink attack.
    export HADOOP_PID_DIR=${HADOOP_PID_DIR}

mkdir /data/tmp  
chmod -R 777 /data/tmp  
export HADOOP\_PID\_DIR=/data/tmp

[20190613093517747.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/20/1096f3ed8c1a446c95224587e8b7247f.png
[stop-all.sh]: http://xn--stop-all-q86n.sh
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNjg4NDcy_size_16_color_FFFFFF_t_70]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/20/db558ef72ae645ce976d9e2557383ad6.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQzNjg4NDcy_size_16_color_FFFFFF_t_70 1]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/20/44caf5bbd2b04cdaa0f881a6e32d0f33.png