SEO Description: The Synology RX6025sas is a high-density 60-bay 4U rackmount expansion unit designed for seamless storage scalability with Synology HD6500 NAS systems. Supporting both 3.5" SAS hard drives and 2.5" SATA SSDs with hot-swappable drive bays, this expansion unit delivers massive storage capacity for large-scale warm and cold storage applications. Features dual mini-SAS HD (SFF-8644) ports for input and output connectivity, enabling daisy-chaining of up to four RX6025sas units for a total of 300 drive bays. SAS multipathing technology provides up to double the performance when deploying multiple expansion units while ensuring resiliency against hardware failures through alternate physical paths for automatic data rerouting. Built with dual redundant 1300W power supplies and hot-swappable system fans to maintain continuous uptime during component replacement or maintenance. Plug-and-play design with online storage expansion allows adding new volumes or expanding RAID arrays without disrupting services on the HD6500. Managed through Synology DiskStation Manager (DSM) with intuitive setup and comprehensive management tools for streamlined deployment. Compatible with Synology enterprise drives including HAT5300, HAS5300, and SAT5200 series for optimal integration and performance. Ideal for enterprise data centers, large-scale backup repositories, video post-production, and surveillance deployments requiring flexible, reliable storage expansion. Note: 2.5" drive trays (R5) must be purchased separately for SSD installation. Backed by Synology's quality engineering and reliability standards for mission-critical operations.