Enterprise NAS with built-in service continuity engineered for data-intensive applications. Securing your business assets The 16-bay RS4021xs+ provides solid data security and lightning-fast performance. Together with its 8-core processor,ECC memory,advanced snapshot technology,and built-in 10GbE connectivity,the RS4021xs+ can support large multi-user environments while handling data-intensive workloads. Engineered for service continuity The RS4021xs+ ensures mission-critical data is always available,enabling businesses to deliver great results,even in the face of disaster. Redundant power Dual PSUs provide protection against a PSU failure or accidental cord removal while hot-swappable fans can be replaced without powering down the system. Maximize service availability Synology High Availability (SHA) pairs two identical units together creating an active-passive cluster with minute-level failover. Next-generation file system Btrfs prevents data corruption and reduces maintenance overheads with advanced storage technologies and optimized snapshots. Customized to your business The RS4021xs+ includes two PCIe slots for performance,networking,and storage upgrades enabling it to adapt to any business environment. Hyper Backup A comprehensive backup and recovery solution for securing data stored on Synology servers. Backup data locally,to another Synology device,rsync server,or cloud-based storage such as Google Drive,Dropbox,S3-compatible destinations,and Synology C2. Deduplication,integrity checks,and incremental transfer technology reduce bandwidth and storage use. Snapshot replication Easily schedule flexible point-in-time backups of shared folders and iSCSI LUNs with an RPO as low as 5 minutes and recovery in seconds. Set up replication and failover to other Synology storage systems for fast RTOs and minimal service disruption. Active backup suite Enables administrators to easily backup the entire IT infrastructure to their NAS,including Windows and Linux workstations and servers,file servers,VMware and Hyper-V virtual machines,and Microsoft 365 and Google Workspace accounts. Backups benefit from deduplication,multiversioning,and optimizations to reduce bandwidth and storage used.