YARN (Yet Another Resource Manager) is a default resource manager in Hadoop2. You can use YARN to manage resources for external applications as well, such as Elasticsearch, with the ES-Hadoop connector. With the support of ES-Hadoop, YARN can manage resources for the Elasticsearch cluster, such as the number of CPU cores, the minimum and maximum RAM, and the local or network storage (such as HDFS).
At the time of writing this book, support for YARN is still being used for experimental purposes in ES-Hadoop. However, to get a glimpse of how YARN can manage your Elasticsearch clusters, here are some quick steps:
Download
elasticsearh-yarnas follows:$ wget –O /opt/lib/elasticsearh-yarn-2.1.1.jar http://central.maven.org/maven2/org/elasticsearch/elasticsearch-yarn/2.1.1/elasticsearch-yarn-2.1.1.jarThen, download the latest Elasticsearch version with Elasticsearch-yarn, as shown in the following command:
$ hadoop jar elasticsearch-yarn-2.1.1.jar –download-es download.local...