Alfresco supports use of the Solr Enterprise search platform for searching within the Alfresco repository. Also, the existing embedded Lucene index remains available.
The way that you configure Alfresco to use Solr depends on how you have installed Alfresco.
By default, communication between Alfresco repository and Solr is protected by SSL with mutual authentication. Both the repository and Solr have their own standard public/private key pair. To secure the two-way communication between the repository and Solr, you must generate your own keys.
Calculate the memory needed for Solr nodes
Solr can have high memory requirements. You can use a formula to calculate the memory needed for the Alfresco internal data structures used in Solr for PATH queries and read permission enforcement.
Transactional metadata query
Alfresco supports the execution of a subset of the CMIS Query Language (CMIS QL) and Alfresco Full Text Search (AFTS) queries directly against the database. This feature is called transactional metadata query (TMDQ).