Pluggable Enterprise Search
Search as a Web Plugin #
As an alternative to using Lucene, Liferay 5.1 now supports pluggable search engines. The first implementation of this uses the open source search engine Solr, but in the future there will be many such plugins for your search engine of choice. This allows you to use a completely separate product from Liferay which can be installed on any application server in your environment. Your search engine then operates completely independently of your Liferay Portal nodes in a clustered environment, acting as a search service for all of the nodes simultaneously.
What this does is solve the problem in a cluster with sharing Lucene indexes. You can now share one search index among all of the nodes of your cluster without having to worry about putting it in a database (if you wish, you can still do this if you configure Solr or another search engine that way) or maintaining separate search indexes on all of your nodes. Each Liferay node will send requests to the search engine to update the search index when needed, and these updates are then queued and handled automatically by the search engine.