The Synology RX1217RP and RX1217 are 12-bay 2U rackmount expansion units designed to seamlessly expand storage capacity for compatible Synology RackStation NAS servers. Featuring 12 hot-swappable drive bays supporting both 3.5" and 2.5" SATA III hard drives and SSDs, these expansion units connect via high-bandwidth Infiniband cable to ensure maximum data throughput and smooth operation. The RX1217RP includes dual redundant 500W power supplies for automatic failover support and enhanced 24/7 reliability, while the RX1217 features a single 500W power supply for cost-effective deployment. Both models support online RAID volume expansion without reformatting existing drives, ensuring service continuity during capacity upgrades, and can serve as dedicated local backup destinations for comprehensive data protection. Equipped with three 80mm cooling fans and intelligent power management that automatically synchronizes with the connected RackStation, these units feature energy-saving hibernation modes to extend drive lifespan. The expansion units integrate seamlessly with Synology DiskStation Manager (DSM) for centralized management, backed by a 5-year limited warranty.