Nexentastor is an enterprise-class unified storage solution built upon the foundation of the open-source file system Nexenta Core Platform, including the ZFS file system. Nexentastor adds to the open source foundation a complete set of managed features, including ZFS and synchronous block level replication, integrated search, console and graphical user interfaces, and optional advanced features, such as management of storage for leading virtualised environments, enhanced mapping and management for Fiber Channel and iSCSI environments, and active/active high availability. A free "developer's edition" based on the most recent stable Nexenta Core Platform is available free of charge for users with less than 4 terabyte of used disk space.