hadoop setup

Introduction HDFs is not good at storing small files, because each file at least one block, each block of metadata will occupy memory in the Namenode node, if there are such a large number of small files, they will eat the Namenode node's large amount of memory. Hadoop archives can effectively handle these issues, he can archive multiple files into a file, archived into a file can also be transparent access to each file, and can be used as a mapreduce

, And the other slave nodes have nodemanger. This is the process for managing the resources of each node, it indicates that the startup is successful, and yarn also provides the Web end. The port is 8088, Enter hadoop000: 8088 in the browser: Pay attention to the content circled above We can start a simple job and test it. [[emailprotected] hadoop]# pwd/root/app/hadoop/share/

Preface After a while of hadoop deployment and management, write down this series of blog records. To avoid repetitive deployment, I have written the deployment steps as a script. You only need to execute the script according to this article, and the entire environment is basically deployed. The deployment script I put in the Open Source China git repository (http://git.oschina.net/snake1361222/hadoop_scripts ). All the deployment in this article is b

As a matter of fact, you can easily configure the distributed framework runtime environment by referring to the hadoop official documentation. However, you can write a little more here, and pay attention to some details, in fact, these details will be explored for a long time. Hadoop can run on a single machine, or you can configure a cluster to run on a single machine. To run on a single machine, you only

ObjectiveWhat is Hadoop?In the Encyclopedia: "Hadoop is a distributed system infrastructure developed by the Apache Foundation." Users can develop distributed programs without knowing the underlying details of the distribution. Take advantage of the power of the cluster to perform high-speed operations and storage. ”There may be some abstraction, and this problem can be re-viewed after learning the various

Hadoop consists of two parts: Distributed File System (HDFS) Distributed Computing framework mapreduce The Distributed File System (HDFS) is mainly used for the Distributed Storage of large-scale data, while mapreduce is built on the Distributed File System to perform distributed computing on the data stored in the distributed file system. Describes the functions of nodes in detail. Namenode: 1. There is only one namenode in the

Hadoop cluster needs SSH login without password, we setCD ~/.sshssh-keygen-t RSA #一直按回车就可以CP Id_rsa.pub Authorized_keys After Setup, we have no password to log on to this machine for testingSSH localhost network configuration In/etc/hosts, add the following cluster information: 192.168.1.103 WLW 192.168.1.105 zcq-pc It is important to note that the cluster information needs to be added on all hosts (maste

Previously introduced me in Ubuntu under the combination of virtual machine Centos6.4 build hadoop2.7.2 cluster, in order to do mapreduce development, to use eclipse, and need the corresponding Hadoop plugin Hadoop-eclipse-plugin-2.7.2.jar, first of all, in the official Hadoop installation package before hadoop1.x with Eclipse Plug-ins, And now with the increase

introduce the installation and use of each product separately, summarize my learning route with my experience.Hadoop Hadoop Learning Roadmap Yarn Learning Roadmap Build Hadoop projects with Maven Hadoop Historical Version Installation Hadoop Programming Calls HDFs Massive Web log analysis

This article has agreed:Dn:datanodeTt:tasktrackerNn:namenodeSnn:secondry NameNodeJt:jobtrackerThis article describes the communication protocol between the Hadoop nodes and the client.Hadoop communication is based on RPC, a detailed introduction to RPC you can refer to "Hadoop RPC mechanism introduce Avro into the Hadoop RPC mechanism"Communication between nodes

Opening: Hadoop is a powerful parallel software development framework that allows tasks to be processed in parallel on a distributed cluster to improve execution efficiency. However, it also has some shortcomings, such as coding, debugging Hadoop program is difficult, such shortcomings directly lead to the entry threshold for developers, the development is difficult. As a result, HADOP developers have devel

Hadoop development is divided into two components: the build of Hadoop clusters, the configuration of the Eclipse development environment. Several of the above articles have documented my Hadoop cluster setup in detail, A simple Hadoop-1.2.1 cluster consisting of a master an

I built a Hadoop2.6 cluster with 3 CentOS virtual machines. I would like to use idea to develop a mapreduce program on Windows7 and then commit to execute on a remote Hadoop cluster. After the unremitting Google finally fixI started using Hadoop's Eclipse plug-in to execute the job and succeeded, and later discovered that MapReduce was executed locally and was not committed to the cluster at all. I added 4 configuration files for

We all know that an address has a number of companies, this case will be two types of input files: address classes (addresses) and company class (companies) to do a one-to-many association query, get address name (for example: Beijing) and company name (for example: Beijing JD, Beijing Associated information for Red Star).Development environmentHardware environment: Centos 6.5 server 4 (one for master node, three for slave node)Software Environment: Java 1.7.0_45,

Word count is one of the simplest and most well-thought-capable programs, known as the MapReduce version of "Hello World", and the complete code for the program can be found in the Src/example directory of the Hadoop installation package. The main function of Word counting: count the number of occurrences of each word in a series of text files, as shown in. This blog will be through the analysis of WordCount source code to help you to ascertain the ba

extract KPI statistic index Build a movie recommendation system with Hadoop Create a Hadoop parent virtual machine Cloning virtual machines adds Hadoop nodes R Language for Hadoop injection statistics blood One of the Rhadoop Practice series Hadoop Envir

1) HDFs File System Preparation workA) # Hadoop fs–ls/user/root #查看hdfs文件系统b) # Hadoop fs-rm/user/root/output02/part-r-00000c) Delete the document, delete the folderd) # Hadoop fs-rm–r/user/root/output02e) # Hadoop fs–mkdir–p INPUT/NCDCf) Unzip the input file and Hadoop does

, according to my personal experience, mostly a permissions issue, check if Hadoop has sufficient permissions, it is recommended that Hadoop be added to the Sudoers list and the root user group. In addition, here are also some of the reasons for the failure of SSH password settings, please move to SSH password-free setup Failure reason summary Four install

This article details how to build a Hadoop project and run it through Mvn+eclipse in the Windows development environment Required environment Windows7 operating System eclipse-4.4.2 mvn-3.0.3 and build the project schema with MVN (see http://blog.csdn.net/tang9140/article/details/39157439) hadoop-2.5.2 (directly on the Hadoop website htt

Install Hadoop fully distributed (Ubuntu12.10) and Hadoop Ubuntu12.10 in Linux Hadoop installation is very simple. You can download the latest versions from the official website. It is best to use the stable version. In this example, three machine clusters are installed. The hadoop version is as follows:Tools/Raw Mater