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, and rich document (e.g., Word, PDF) handling. I use this on OpenSUSE and Debian (minor tweaks on Debian, just paths to correct but it’s almost the same). Packages from 4 of March 2011.
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