hadoop环境搭建与測试

搭建參看：

http://blog.csdn.net/w13770269691/article/details/16883663/

查看集群状态：

[root@master bin]# hdfs dfsadmin -report 
Configured Capacity: 36729053184 (34.21 GB) 
Present Capacity: 13322559491 (12.41 GB) 
DFS Remaining: 13322240000 (12.41 GB) 
DFS Used: 319491 (312.00 KB) 
DFS Used%: 0.00% 
Under replicated blocks: 0 
Blocks with corrupt replicas: 0 
Missing blocks: 0 

------------------------------------------------- 
Datanodes available: 2 (2 total, 0 dead) 

Live datanodes: 
Name: 192.168.137.103:50010 (slave2) 
Hostname: slave2 
Decommission Status : Normal 
Configured Capacity: 18364526592 (17.10 GB) 
DFS Used: 45056 (44 KB) 
Non DFS Used: 11702558720 (10.90 GB) 
DFS Remaining: 6661922816 (6.20 GB) 
DFS Used%: 0.00% 
DFS Remaining%: 36.28% 
Last contact: Thu Nov 06 21:26:34 CST 2014 


Name: 192.168.137.102:50010 (slave1) 
Hostname: slave1 
Decommission Status : Normal 
Configured Capacity: 18364526592 (17.10 GB) 
DFS Used: 274435 (268.00 KB) 
Non DFS Used: 11703934973 (10.90 GB) 
DFS Remaining: 6660317184 (6.20 GB) 
DFS Used%: 0.00% 
DFS Remaining%: 36.27% 
Last contact: Thu Nov 06 21:26:31 CST 2014

查看文件块组成：

[root@master bin]# hdfs fsck / -files -blocks 
Status: HEALTHY 
Total size: 219351 B 
Total dirs: 11 
Total files: 12 
Total symlinks: 0 
Total blocks (validated): 10 (avg. block size 21935 B) 
Minimally replicated blocks: 10 (100.0 %) 
Over-replicated blocks: 0 (0.0 %) 
Under-replicated blocks: 0 (0.0 %) 
Mis-replicated blocks: 0 (0.0 %) 
Default replication factor: 1 
Average block replication: 1.0 
Corrupt blocks: 0 
Missing replicas: 0 (0.0 %) 
Number of data-nodes: 2 
Number of racks: 1 
FSCK ended at Thu Nov 06 21:27:34 CST 2014 in 29 milliseconds 


The filesystem under path '/' is HEALTHY 
[root@master bin]#
[hadoop@master hadoop2.2]$

查看各节点状态：

http://192.168.56.101:50070

查看ResourceManager上cluster执行状态：

http://192.168.56.101:8088

在环境搭建的过程中，假设出现不论什么问题。都要去查看日志

日志路径是：/home/hadoop/hadoop2.2/logs

在配置完毕HADOOP_HOME之后，而且使之生效，那么接下来就进行測试，启动hadoop

首先在/文件夹下创建input文件

[root@master /]# vim input。在该文件里输入例如以下内容：I am a very good person! I love you America !
将之上传到hdfs上：[root@master /]# hadoop fs -put /input /input
在hadoop的bin文件夹下运行：[root@master bin]# ./yarn jar ../share/hadoop/mapreduce/hadoop-mapreduce-examples-2.2.0.jar wordcount /input /output
这样运行完成之后能够看到：output文件夹下有两个文件
[root@master ~]# hadoop fs -ls /output 
Found 2 items 
-rw-r--r-- 1 root supergroup 0 2014-11-06 21:21 /output/_SUCCESS 
-rw-r--r-- 1 root supergroup 64 2014-11-06 21:21 /output/part-r-00000
接着能够查看Wordcount的统计结果：
[root@master bin]# hadoop fs -cat /output/part-r-00000 
! 1 
America 1 
I 2 
a 1 
am 1 
good 1 
love 1 
person! 1 
very 1 
you 1 
[root@master bin]#