Storage Manager is a DSM application that lets you monitor storage usage and manage drives, storage pools, volumes, and SSD caches on a Synology storage system.
Synology storage system uses RAID technology to combine multiple drives into a single data storage space for fault tolerance and improved performance.
Volumes can use either the Btrfs or ext4 file system to store data.
SSD cache can improve system performance.
Storage consumption on Btrfs volumes can be reduced through supported storage efficiency features.
Connected expansion units can be monitored and configured in Storage Manager.
Storage Pools and Volumes
Supports the following RAID types: Basic, SHR-1, SHR-2, JBOD, RAID 0, RAID 1, RAID 5, RAID 6, RAID 10, and RAID F1.
Supports RAID Group to improve drive fault tolerance in large drive number deployment.
Supports the following storage pool operations:
Add drives in a storage pool for expansion.
Change the RAID type of a storage pool.
Replace drives in a storage pool for expansion or repair.
Safely eject a storage pool from an expansion unit.
Assemble a storage pool online when enough drives are detected.
Available storage pool operations depend on the RAID type and other requirements. Refer to the help articles for details about each operation.
SSD TRIM is supported only on certain Synology storage system and SSD models. For compatibility details, refer to the datasheet for your storage system and the Notes section for your SSD in the Synology Products Compatibility List.
Space reclamation is only available for reclaiming space in Btrfs volumes.
Volume encryption key vaults enabled on DSM 7.2 must be upgraded and reset to use full functionality. (Learn more)
Encrypted volumes require either the recovery key or key vault password when the key vault is unavailable; otherwise, the volume cannot be accessed. (Learn more)
File System
ext4 File System
Single volume size: 10 GiB to 200 TiB
Maximum single file size: 16 TiB
Maximum file name length: 255 bytes
Maximum path name length: 4,096 bytes
Maximum symbolic link depth: 40
Recommended maximum number of files per folder in the same level: 100,000
Run file system defragmentation to improve the file access performance.
Enable storage efficiency features:
SSD volumes: Data deduplication (Applied to the entire volume)
HDD volumes: Data deduplication and compression (Applied to individual shared folders)
Supports performing file self-healing to automatically detect and recover silent data corruption on metadata and data.
Supports copying data instantly via the SMB protocol when the source and destination of the data are located in the same Btrfs volume.
Supports taking snapshots and creating replication tasks for shared folders and LUNs.
Requirements and Limitations
Refer to your model's datasheet for the supported file system and maximum volume size.
Storage efficiency features are supported only on specific Synology models using Synology SSDs or HDDs. (Learn more)
The byte length of file and path names varies by character encoding. For example, one UTF-8 character can occupy 1 to 4 bytes.
The data checksum option must be enabled on a shared folder before silent data corruption detection can take effect. (Only SHR with at least 2 drives, RAID 1, RAID 5, RAID 6, RAID 10, and RAID F1 support corrupted data recovery.)
Drive Management
Supports S.M.A.R.T. tests for monitoring drive health.
Supports Secure Erase to permanently remove the data from drives.
Support firmware update for Synology drives.
Support write cache to optimize the system performance.
Requirements and Limitations
Feature availability varies by drive model.
SSD Cache
Supports creating read-only caches and read-write caches:
Up to 16 volumes can be mounted with SSD caches at a time.
Metadata of Btrfs volumes can be pinned to read-write caches. (Learn more)
Supports the SSD cache group feature to aggregate and allocate the capacity of SSDs for caching.
Volumes in the same storage pool must use capacity from the same SSD cache group to create SSD cache.
Supports SSD cache group management options, including drive addition and replacement, and changing the RAID type.
SSD cache requires approximately 400 KiB of system memory per 1 GiB of SSD cache (including expandable memory) and no more than 25% of the pre-installed system memory.
Data Scrubbing
Storage Manager supports data scrubbing to ensure data integrity.
The speed limit for data scrubbing can be adjusted.
During Data Scrubbing, file system scrubbing (only supported on the Btrfs file system) and RAID scrubbing (only supported on SHR with at least 3 drives, RAID 5, RAID 6, and RAID F1) will run sequentially.