六： Image Viewer 离线镜像查看器

参考：http://hadoop.apache.org/docs/r2.6.3/hadoop-project-dist/hadoop-hdfs/HdfsImageViewer.html

  离线镜像查看器用于查看HDFS镜像。hadoop2.4之前的镜像查看器与之后的不同，要查看2.4之前的，请用2.3的查看器，或者用oiv_legacyCommand 命令。

输出格式：

1)web http(默认方式)

2)XML

使用方式：

1)web方式

首先启动HTTP REST:

列出有哪些目录:

查看指定目录:

2)XML方式

将fsimage里的内容dump到xml中

命令选项:

Flag	Description
-i|--inputFile input file	Specify the input fsimage file to process. Required.
-o|--outputFile output file	Specify the output filename, if the specified output processor generates one. If the specified file already exists, it is silently overwritten. (output to stdout by default)
-p|--processor processor	Specify the image processor to apply against the image file. Currently valid options are Web (default), XML and FileDistribution.
-addr address	Specify the address(host:port) to listen. (localhost:5978 by default). This option is used with Web processor.
-maxSize size	Specify the range [0, maxSize] of file sizes to be analyzed in bytes (128GB by default). This option is used with FileDistribution processor.
-step size	Specify the granularity of the distribution in bytes (2MB by default). This option is used with FileDistribution processor.
-h|--help	Display the tool usage and help information and exit. 来源： http://hadoop.apache.org/docs/r2.6.5/hadoop-project-dist/hadoop-hdfs/HdfsImageViewer.html

来自为知笔记(Wiz)