Charm Needed: SolrCloud

Website: http://wiki.apache.org/solr/SolrCloud

Description: Solr is the popular, blazing fast open source enterprise search platform from the Apache Lucene project. Its major features include powerful full-text search, hit highlighting, faceted search, dynamic clustering, database integration, rich document (e.g., Word, PDF) handling, and geospatial search. Solr is highly scalable, providing distributed search and index replication, and it powers the search and navigation features of many of the world's largest internet sites. SolrCloud is the set of Solr features that take Solr's distributed search to the next level, enabling and simplifying the creation and use of Solr clusters, with central configuration for the entire cluster and automatic load balancing and fail-over for queries. Zookeeper is integrated and used to coordinate and store the configuration of the cluster.

Solr Project Site: http://lucene.apache.org/solr/

Notable users of Solr: http://wiki.apache.org/solr/PublicServers