Build hadoop pseudo-distributed in CentOS 6.3

Set up hadoop pseudo-distributed in CentOS 6.3 to install CentOS 6.3 in Basic Server mode, set the machine name to hadoop1.cloud.com, and write hadoop1.cloud.com to the end of 127.0.0.1 in/etc/hosts. 1. Install jdk, I am relatively lazy, so direct yum, this saves the trouble of configuring the environment variable [plain] yum install java-1.6.0-openjdk java-1.6.0-openjdk-devel-y 2, configuring the native password-less login [plain] ssh-keygen-t dsa-p'-f ~ /. Ssh/id_dsa cat. ssh/id_dsa.pub>. ssh/authorized_keys can ssh localhost, no password can be logged on that the configuration is successful 3, download and install hadoop, I am using a hadoop-1.2.1, directly download the rpm installation official website download successful, run the command: [plain] rpm-Uvh hadoop-1.2.1-1.x86_64.rpm 4, modify/etc/hadoop/hadoop-env.sh, change JAVA_HOME to true real value because it is a yum installation, so it is the default setting, you need to modify: [plain] export JAVA_HOME =/usr/lib/jvm/java-1.6.0-openjdk-1.6.0.0.x86_64/