hadoop directory structure

[[Email protected] bin] #./hadoop namenode-format 12/05/21 06:13:51 info namenode. namenode: startup_msg: /*************************************** ********************* Startup_msg: Starting namenode Startup_msg: host = nn01/127.0.0.1 Startup_msg: ARGs = [-format] Startup_msg: version = 0.20.2 Startup_msg: Build = https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20-r 911707; compiled by 'chr

in the Master/Slave structure. A cluster has a Name node, that is, the master control server, which is responsible for managing the file system namespace and coordinating the customer's access to files. There are also a bunch of data nodes, usually one deployed on a physical node, responsible for the Storage Management on the physical node where they are located. HDFS opens the namespace of the file system so that user data can be stored in files. In

Statement: Personal originality. for reprinting, please indicate the source. I have referenced some online or book materials in this article. Please tell me if there is anything wrong. This article is the note I wrote when I read hadoop 0.20.2 for the second time. I encountered many problems during the reading process and finally solved most of the problems through various ways. The entire hadoop system is

Safe Mode1, namenode start, merge image and edit into new image, and generate a new edit log2, the entire intelligent Safe mode, the client can only read3. Check if Nameode is in safe modeHDFs Dfsadmin-safemode Get//view Safe ModeHDFs Dfsadmin-safemode Enter//Enter Safe modeHDFs Dfsadmin-safemode Leave//Leave Safe ModeHDFs Dfsadmin-safemode Wait//await Safe mode4. Manually Save namespaces: Dfsadmin-savenamespace5. Manually save the image file: HDFs dfsadmin-fetchimage6. Save metadata: (Save unde

transferred from: http://blog.csdn.net/lifuxiangcaohui/article/details/40588929Hive is based on the Hadoop distributed File system, and its data is stored in a Hadoop Distributed file system. Hive itself does not have a specific data storage format and does not index the data, only the column separators and row separators in the hive data are told when the table is created, and hive can parse the data. So i

----Configuration----- ---is associated with this configuration estimate, which looks like a directory problem---- ------------Command---------- Hadoop fs-copyfromlocal input/ncdc/micro/1901/user/administrator/input/ncdc/micro/1901 --------------Error-------- CopyFromLocal:java.io.FileNotFoundException:Parent path is not a directory:/user/administrator ---------S

Write more verbose, if you are eager to find the answer directly to see the bold part of the .... (PS: What is written here is all the content in the official document of the 2.5.2, the problem I encountered when I did it) When you execute a mapreduce job locally, you encounter the problem of No such file or directory, follow the steps in the official documentation: 1. Formatting Namenode Bin/hdfs Namenode-format 2. Start the Namenode and Datanod

Run the Hadoop fs-ls command to display local Directory issues Problem reason: The default path for HDFS is not specified in the Hadoop configuration file Solution: There are two ways 1. Access Hadoop fs-ls hdfs://192.168.1.1:9000/using HDFs full path 2. Modify the configuration file Vim/opt/cloudera/parcels/cd

After using Cygwin to install Hadoop, enter the command ./hadoop version The following error occurred ./hadoop:line 297:c:\java\jdk1.6.0_05\bin/bin/java:no such file or directory ./hadoop:line 345:c:\java\jdk1.6.0_05\bin/bin/java:no such file or directory ./hadoop:line 345:exec:c:\java\jdk1.6.0_05\bin/bin/java:canno

Label: style blog color Io OS ar Java I restarted the hadoop cluster today and reported an error when I used eclipse to debug HDFS APIs: [Warning] java. Lang. nullpointerexception at org. Conan. Kafka. hdfsutil. batchwrite (hdfsutil. Java:50) At org. Conan. Kafka. singletopicconsumer. Run (singletopicconsumer. Java:144) At java. Lang. thread. Run (thread. Java:745) At java. util. Concurrent. threadpoolexecutor. runworker (threadpoolexecutor. Java:11

mainly by two types of nodes: one namenode (that is, master) and multiple Datanode (that is, slave), as shown in the framework diagram:2.2 NameNode, DataNode, Jobtracker and Tasktracker Namenode is a master server that manages the namespace and metadata of the entire file system and handles file access requests from outside. Namenode saves three types of metadata for the file system: Namespaces: The directory