Setting up Hadoop

If you want to run Apache Mahout in local mode (without Hadoop), then you need to set some value for the MAHOUT_LOCAL environment variable, as follows:

Set MAHOUT_LOCAL=true

Also, if HADOOP_HOME is not set, then Apache Mahout runs locally.

So, if you want to run Apache Mahout with Hadoop, then there are three possible options available:

• Local mode

• The pseudo-distributed mode

• The fully-distributed mode

You can select the Hadoop mode that best suits you, depending on the requirement at hand.

Setting up Mahout in local mode

Local mode is the simplest of all modes in Hadoop with the least number of configuration changes.

Hadoop is running as a single JVM instance in this mode. Hadoop daemons, such as resource manager, name node, node manager, data nodes, and secondary node are not running. Also, there is no HDFS-related file processing with this mode.

Prerequisites

The Hadoop framework is an open source software implementation in Java.

Java installation

Hadoop requires Java 7 or a later...