By default, communication between Alfresco repository and Solr 4 is protected by SSL with mutual authentication. Both the repository and Solr 4 have their own standard public/private key pair. To secure the two-way communication between the repository and Solr 4, you must generate your own keys.
Note: Every Alfresco installation is supplied with a generic certificate and SSL keys. For security reasons, it is advised that you generate a new set of keys to secure you Solr communication and access to the Solr Admin Console. For more information, see Configuring Solr and Generating secure keys for Solr communication.