No, Alfresco scales very well in the web, application, and database layers. A typical high availability installation would consist of Apache web servers in the DMZ as SSL terminators, caching of static content, URL rewrite, and load-balancing between the nodes in the Alfresco server cluster, which can be scaled separately to the web layer and the database layer. The database layer can also be scaled separately via MySQL Master-Slave or for example PostgreSQL XtraDB cluster. The meta-data (database files) and content (content files and index) is typically stored on a SAN (such as a NetApp), making it easy to support a DR scenario. You provision application files and configuration via Puppet and content files, index, and database files are managed by the SAN.