This article aims to assist you with installing Apache Solr.
For more information on Solr, please see the following article: What is cpanelsolr?
As the root user, log in to your WHM and access the "Manage Plugins" tool. On this page, you will find the option to install cPanel Solr.
By selecting the button labeled 'Install “Full Text Search Indexing for IMAP powered by Apache Solr™”', the installation process will begin.