hadoop vm

Chapter 1 Meet HadoopData is large, the transfer speed is not improved much. it's a long time to read all data from one single disk-writing is even more slow. the obvious way to reduce the time is read from multiple disk once.The first problem to solve is hardware failure. The second problem is that most analysis task need to be able to combine the data in different hardware. Chapter 3 The Hadoop Distributed FilesystemFilesystem that manage storage h

[User6 @ das0 hadoop-0.20.203.0] $ bin/hadoop namenode-format12/02/20 14:05:17 info namenode. namenode: startup_msg: Re-format filesystem in/data0/hadoop-name? (Y or N) yformat aborted in/data0/hadoop-name12/02/20 14:05:20 info namenode. namenode: shutdown_msg: Then hadoop

/profile (2) Add a variable, #set java environment export JAVA_HOME=/usr/local/java/jdk1.6.0_30export JRE_HOME=/usr/local/java/jdk1.6.0_30/jreexport CLASSPATH=.:$JAVA_HOME/lib:$JRE_HOME/lib:$CLASSPATH export PATH=$JAVA_HOME/bin:$JRE_HOME/bin:$JAVA_HOME:$PATH Generally, after changing the/etc/profile file, you need to restart the machine to make it take effect. Here, you can use the following command to make the configuration file take effect immediately, source /etc/profile (3) check whether

. | = o. | o |. | + --------------- + [hadoop @ ipython ~] $ Cat ~ /. Ssh/id_dsa.pub> ~ /. Ssh/authorized_keys [hadoop @ ipython ~] $ Chmod 0600 ~ /. Ssh/authorized_keys 2, JAVA. JDK has been installed (please refer to: [CentOS JDK-1.8 installation ]) [Hadoop @ ipython ~] $ Java-versionjava version "1.8.0 _ 25" Java (TM) SE Runtime Environment

Hadoop cannot be started properly (1) Failed to start after executing $ bin/hadoop start-all.sh. Exception 1 Exception in thread "Main" Java. Lang. illegalargumentexception: Invalid URI for namenode address (check fs. defaultfs): file: // has no authority. Localhost: At org. Apache. hadoop. HDFS. server. namenode. namenode. getaddress (namenode. Java: 214) Localh

the page where the results are checked"Cloudera recommended setting/proc/sys/vm/swappiness to 0 when checking host correctness." The current setting is 30. "Warning, make the following settings# vi/etc/sysctl.confvm.swappiness = 0# sysctl–pWhen checking host correctness, the "enabled" transparent large page appears, which can cause significant performance issues. "Warning, make the following settingsecho never >/sys/kernel/mm/transparent_hugepage/ena

Cluster configuration is similar, here I briefly say my configuration:The master node system is Ubuntu 14.04 LTS x64 other two nodes in the VM system for the CentOS 6.4 x64JVM is jdk1.7_80Hadoop versions 2.7.1 and 2.7.2 have triedThe problems that arise are:Start HDFs system OK, all started up, JPS see the followingMaster Nodes Secondarynamenode and NameNodeFrom node: DataNodeBut using the Hfds command Dfsadmin-report found that there are only 1 Datan

First explain the configured environmentSystem: Ubuntu14.0.4Ide:eclipse 4.4.1Hadoop:hadoop 2.2.0For older versions of Hadoop, you can directly replicate the Hadoop installation directory/contrib/eclipse-plugin/hadoop-0.20.203.0-eclipse-plugin.jar to the Eclipse installation directory/plugins/ (and not personally verified). For HADOOP2, you need to build the jar f

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

Hadoop In The Big Data era (1): hadoop Installation If you want to have a better understanding of hadoop, you must first understand how to start or stop the hadoop script. After all,Hadoop is a distributed storage and computing framework.But how to start and manage t

Java environment, if you do not know whether to install the Java environment, you can enter the terminal: Java-version view, as seen below: Java version "1.6.0_65" Java (tm) SE Runtime Environment (build 1.6.0_65-b14-462-11m4609) Java HotSpot (tm) 64- Bit Server VM (build 20.65-b04-462, Mixed mode)It proves that the Java environment has been installed, if the Java environment is not installed child paper can download the JDK for installation, this st

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

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