“hadoop fs"和“hadoop fs"有什么区别?shell 命令和“hdfs dfs"外壳命令?
它们应该相等吗?
但是,为什么hadoop fs
"命令显示hdfs files
而hdfs dfs
"命令显示本地文件?
but, why the "hadoop fs
" commands show the hdfs files
while the "hdfs dfs
" commands show the local files?
这里是hadoop版本信息:
here is the hadoop version information:
Hadoop 2.0.0-mr1-cdh4.2.1 颠覆git://ubuntu-slave07.jenkins.cloudera.com/var/lib/jenkins/workspace/CDH4.2.1-Packaging-MR1/build/cdh4/mr1/2.0.0-mr1-cdh4.2.1/source-r 由 jenkins 于 2013 年 4 月 22 日星期一 10:48:26 PDT 编译
Hadoop 2.0.0-mr1-cdh4.2.1 Subversion git://ubuntu-slave07.jenkins.cloudera.com/var/lib/jenkins/workspace/CDH4.2.1-Packaging-MR1/build/cdh4/mr1/2.0.0-mr1-cdh4.2.1/source -r Compiled by jenkins on Mon Apr 22 10:48:26 PDT 2013
以下是三个看似相同但有细微差别的命令
Following are the three commands which appears same but have minute differences
- hadoop fs {args}
- hadoop dfs {args}
- hdfs dfs {args}
hadoop fs <args>
FS 与通用文件系统相关,它可以指向任何文件系统,如本地、HDFS 等.因此,当您处理不同的文件系统(如本地 FS、(S)FTP、S3 等)时,可以使用它
FS relates to a generic file system which can point to any file systems like local, HDFS etc. So this can be used when you are dealing with different file systems such as Local FS, (S)FTP, S3, and others
hadoop dfs <args>
dfs 非常特定于 HDFS.将适用于与 HDFS 相关的操作.这已被弃用,我们应该使用 hdfs dfs 代替.
dfs is very specific to HDFS. would work for operation relates to HDFS. This has been deprecated and we should use hdfs dfs instead.
hdfs dfs <args>
与 2nd 相同,即适用于所有与 HDFS 相关的操作,并且是推荐的命令,而不是 hadoop dfs
same as 2nd i.e would work for all the operations related to HDFS and is the recommended command instead of hadoop dfs
以下是归类为 hdfs
命令的列表.
below is the list categorized as hdfs
commands.
namenode|secondarynamenode|datanode|dfs|dfsadmin|fsck|balancer|fetchdt|oiv|dfsgroups
因此,即使您使用 hadoop dfs ,它也会查找 hdfs 并将该命令委托给 hdfs dfs
So even if you use hadoop dfs , it will look locate hdfs and delegate that command to hdfs dfs