hadoop file system commands

commandHadoop FS + commands below-ls -LSR -mkdir -put -get -text -rm[r] Iv. Namenode of HDFsIt is the management node of the entire file system, which maintains a directory tree of the entire file system, meta-information for files/directories, and a list of data blocks cor

Features of the Liststatus method for filesystem: listing content in a directoryWhen the passed parameter is a file, it turns into an array to return the Filestatus object of length 1When the passed-in parameter is a directory, 0 or more Filestatus objects are returned, representing the files and directories contained in this directoryIf you specify a set of paths, the result is the equivalent of passing each path in turn and calling the Liststatus ()

The Hadoop Distributed File system is the Hadoop distributed FileSystem.When the size of a dataset exceeds the storage capacity of a single physical computer, it is necessary to partition it (Partition) and store it on several separate computers, managing a file

Hadoop history Embryonic beginning in 2002, Apache Nutch,nutch is an open source Java implementation of the search engine. It provides all the tools we need to run our own search engine. Includes full-text search and web crawlers.Then in 2003 Google published a technical academic paper Google File system (GFS). GFS is the proprietary

Hadoop HDFs provides a set of command sets to manipulate files, either to manipulate the Hadoop Distributed file system or to manipulate the local file system. But to add theme (Hadoop

Copy local files to the Hadoop File System // Copy the local file to the Hadoop File System// Currently, other Hadoop

Java API for Hadoop file system additions and deletionsThe Hadoop file system can be manipulated through shell commands hadoop fs -xx , as w

It is still the central link for batch delivery to ApacheHadoop through MapReduce ., However, Hadoop (Distributed File System) has experienced significant development as the pressure to obtain competitive advantages from the "super-thinking speed" analysis increases. Technology development allows real-time queries, such as ApacheDrill, ClouderaImpala, and Stinger

more Authorized_keys to viewLog on to 202 on 201 using SSH 192.168.1.202:22Need to do a local password-free login, and then do cross-node password-free loginThe result of the configuration is 201-->202,201-->203, if the opposite is necessary, the main reverse process is repeated above7. All nodes are configured identicallyCopy Compressed PackageScp-r ~/hadoop-1.2.1.tar.gz [Email protected]:~/ExtractTAR-ZXVF hadoo