Introduction of Hadoop HDFS and the use of basic client commands

HDFS basic functions
Basic function
has the basic operation function of file system;

file blocks for unit store the data in different machine disk
the default 128 MB large data slices, 3 copies of the
the NameNode master node: virtual directory maintenance, management of child nodes (Secondly the NameNode) storage resources scheduling, and the client interaction
the DataNode from multiple nodes: save the data, register when they start with the master node, the master node can know the information of it, convenient later call
(DataNode from cluster nodes to meet the basic conditions: Linux01, 02 01… The IP domain name between the secret set. Because nodes communicate with each other)
Linux01:NameNode DataNode
Linux02:DataNode
Linux03:DataNode
Use of client base commands

    location bin/HDFS DFS among them are some commands to upload: HDFS DFS – put./to/(the front is a local path, followed by HDFS path) directory: HDFS DFS – ls/(files in the directory view points, and other road king in the same way) to create folders: HDFS DFS – mkdir/data (create the folder in the root directory) to check the file content: HDFS DFS – cat file path from HDFS download: HDFS DFS get /data/1.txt/(HDFS path in front followed by local path)


Read More: