It's Time to Replace Your External Hard Drives

• The Btrfs file system can perform file self-healing to automatically detect silent data corruption and recover corrupted data (See limitation 1)
• Powerful snapshot feature for creating point-in-time snapshots
• SSD cache support for enhancing system performance

General

• File system types:
  • ext4 and Btrfs (See limitation 2)
  • For external devices: ext4, ext3, FAT32, NTFS, Btrfs, exFAT, HFS, and HFS+ (See limitation 2)
• RAID types:
  • Basic, SHR-1, SHR-2, JBOD, RAID 0, RAID 1, RAID 5, RAID 6, RAID 10, and RAID F1 (See limitation 2)
• RAID conversion:
  • Basic to RAID 1, Basic to RAID 5, RAID 1 to RAID 5, RAID 5 to RAID 6, and SHR-1 to SHR-2
• Up to 512 shared folders, including 128 encrypted ones (See limitation 2)
• Up to 256 volumes (See limitation 2)
• Supports creating global and dedicated hot spare drives
• Supports expanding storage pool and volume capacity (See limitation 6)
• Supports creating SSD read-only caches and SSD read-write caches
  • Can only use a quarter of the pre-installed system memory for SSD cache creation
  • Requires approximately 416 KB of system memory for every 1 GB of SSD cache (Expandable memory included)
• Supports setting volume usage quota
• Supports setting usage and user quota for shared folders in the Btrfs file system
• Supports scheduling data scrubbing to ensure data integrity (See limitation 3)
• Supports adjusting the data scrubbing speed limit, repairing storage pools, expanding storage pools, and changing the RAID types of storage pools
• Supports RAID Group to improve the level of protection (See limitation 5)
• Supports Dynamic Bad Sector Mapping to enhance data integrity during storage pool repair
• Supports complete Windows access control list (ACL)
• Supports encrypting shared folders with AES-256 CBC mode

Drive Management

• Supports HDD hibernation feature for power saving
• Supports SSD TRIM feature for sustained performance
• Supports scheduling S.M.A.R.T. tests
• Supports Seagate IronWolf Health Management (IHM)
• Supports deactivating HDDs while Synology NAS is powered on to prevent service disruption
• Supports switching the LED indicator of a specific drive slot

ext4 File System

• Maximum single file size: 16 TiB
• Maximum file name length: 255 bytes (See limitation 4)
• Maximum path name length: 4,096 bytes (See limitation 4)
• Maximum symbolic link depth: 40
• Maximum single volume size: 200 TiB (See limitation 2)
• Recommended maximum number of files per folder in the same level: 100,000

Btrfs File System

• Maximum single file size: 16 TiB
• Maximum file name length: 255 bytes (See limitation 4)
• Maximum path name length: 4,096 bytes (See limitation 4)
• Maximum symbolic link depth: 40
• Maximum single volume size: 200 TiB (See limitation 2)
• Recommended maximum number of files per folder in the same level: 100,000
• Supports inline compression
• Supports performing file self-healing to automatically detect and recover silent data corruption on metadata and data (See limitation 1)
• Supports copying data instantly via the SMB protocol when the source and destination of the data are located in the same Btrfs volume
• Allows manual implementation of file system defragmentation to enhance system performance
• Integrated with Synology Drive Server and Hyper Backup to enhance storage efficiency and data consistency

Snapshots on the Btrfs File System

• Supports taking snapshots and creating replication tasks for shared folders and LUNs
• Maximum number of snapshots per system:
  • Memory exceeding or equivalent to 2 GB: 65,536
  • Others: 4,096
• Maximum number of snapshots per shared folder:
  • Memory exceeding or equivalent to 2 GB: 1,024
  • Others: 256
• Maximum number of snapshots per LUN:
  • Memory exceeding or equivalent to 2 GB: 256
  • Others: 64
• Supports taking application-consistent snapshots
• Supports browsing read-only snapshots
• Supports Windows Previous Versions feature

1. The data checksum option must be enabled on a shared folder before silent data corruption detection can take effect (Only RAID 1, RAID 5, RAID 6, and RAID F1 support corrupted data recovery)
2. Varies according to models (Refer to here for more information)
3. File system scrubbing (only supported on the Btrfs file system) and RAID scrubbing (only supported on RAID 5, RAID 6, and RAID F1) will run sequentially when data scrubbing is performed
4. Different character encodings may contain different data sizes (e.g., a character with UTF-8 encoding may contain 1 to 4 bytes)
5. RAID Group is available on specific models only (Refer to here for more information)
6. Only certain RAID types support expanding storage pool and volume capacity by adding or replacing drives (Refer to here for more information)

• Synchronization server for clients on various platforms
• Cross-office file collaboration among Synology NAS servers
• File management on web portal
• Integrated with Synology Office for online file editing
• Generates safe and secure file sharing links

• Synology Drive Admin Console
• Synology Drive ShareSync
• Synology Drive

• For Synology Drive Server versions below 3.0:
  • Cloud Station applications, including Cloud Station Drive, Cloud Station Backup, Cloud Station ShareSync, and DS cloud are compatible with Synology Drive Server. That is, the applications will continue to work after Cloud Station Server has been upgraded to Synology Drive Server
  • Synology Drive Client desktop application and Synology Drive ShareSync are compatible with Cloud Station Server. They can continue to function with connection to Cloud Station Server
• For Synology Drive Server versions 3.0 and above:
  • Synology Drive Server 3.0 and above no longer support Cloud Station Suite applications. If you are using any Cloud Station Suite applications (Cloud Station Server, Cloud Station Drive, Cloud Station Backup, Cloud Station ShareSync, or DS cloud), you must switch to their counterparts in the Synology Drive Suite to ensure compatibility
  • Connected Synology Drive client applications, including Synology Drive Client and Synology Drive ShareSync, must be updated to version 3.0 and above to ensure compatibility
• Compatible with DSM 6.2.2 or above
• The following packages from Package Center must be installed first:     - Synology Universal Search     - Synology Application Service

Features

• Service management center for administrators to monitor and control business data assets and resources on Synology Drive
• File synchronization server for corresponding client applications on computers, mobile phones, and other Synology NAS servers
• Option to select specific shared folders on Synology NAS for access in Synology Drive with history version policies
• Flexible settings for users' access and sharing permissions to suit any deployment scenarios
• Point-in-time history version restoration of files and folders

Specifications

• Shared folder service management with versioning policies
  • Up to 32 historical file versions with cross-version deduplication
  • Historical version rotation with duration of 7, 30, 60, or 120 days
  • Retention policy of first-in-first-out method or Intelliversioning algorithm, preserving the most significant file versions
• Recommended number of concurrent computer client connections per Synology NAS: Up to 2,000 (See Note 1)
• Monitors and logs detailed system health status, user actions, and events, including service disruption, modification of shared folder configurations, and file manipulations
• Non-admin users' sharing permission settings, including the ability to share files publicly as well as directly with assigned DSM users and group accounts
• Blacklisting file types (e.g., documents, music, videos, images, etc.), file name, file extensions, and maximum file size for specific users' syncing files
• Connection list of client applications with detailed information (e.g., device name, username, application type, online/offline status, IP address, location) as well as an option to unlink the connection
• Customizable content indexing rules for each shared folders for robust search in Synology Drive
• Calculation of application's storage usage and option to manually clean up deleted files in recycle bins to free up space
• Version Explorer allows administrators to switch view roles, browse file/folder version history, and download/restore them with minute-level version granularity

Limitations

• Mounted shared folders cannot be enabled as team folders

Note

1. The number of concurrent computer client connections may vary for different Synology NAS models (Refer to each Synology NAS model's product spec for the recommended number)

Features

• Real-time collaboration via two-way synchronization with multiple Synology NAS servers in multiple locations
• One-way synchronization to distribute or collect data and files to remote Synology NAS servers
• Flexible options to sync folders and selectively sync sub-folders to prevent redundant file syncing

Specifications

• Sync files on shared folder basis or selectively sync sub-folders with multiple Synology NAS servers
• Flexible sync mode settings with either syncing all privileges, only domain user privileges or files excluding permissions and metadata
• Two-way sync or one-way upload/download to meet different remote offices and collaboration needs
• Blacklisting file types (e.g., documents, music, videos, images, etc.), file name, file extensions, and maximum file size for syncing files and folders for each syncing task
• Options to tackle file version conflict by either keeping the latest modified version, or keeping the version on the server and renaming to keep the discarded version
• Monitors syncing status with information connected servers' information and connection status for error handling
• Monitors and logs detailed file syncing events which can be filtered by shared folders, keywords, or date range

Limitations

• Under the following circumstances, files will not be synced by Synology Drive ShareSync:
  • Certain file types or file paths containing certain characters (Learn more)
  • The file path is longer than 2,048 characters
  • The file name is longer than 255 characters
• Each Synology NAS can connect with multiple host Synology NAS servers, but a Synology NAS can only be paired with the host Synology NAS once
• A local shared folder cannot be set as the sync folder for multiple host Synology NAS servers simultaneously
• User home folders (homes), mounted shared folders, and folders without write permission cannot be used as sync folders
• Files and folders under the mounted folder on the client Synology NAS will not be synced

Features

• File access on web portal and collaboration through team folders with labels and stars to categorize or mark important files
• Granular and flexible file/folder permission settings for secure sharing scenarios
• Integration with the online editing tool Synology Office and instant messaging service Synology Chat for seamless team collaboration

Specifications

• Supported browsers including Firefox, Chrome, Safari, and Internet Explorer 10 or later
• File management with labels, stars, or hotkey, and sorting by title, modified time, type, owner, and size
• Content searching via DSM built-in package Synology Universal Search with a variety of search criteria (e.g., keyword, location, type, owner, labels, size, and date) to quickly gather the most relevant data
• Customizable permission settings to share folders and files only with other DSM users, or share publicly with the protection of password and validity period
• Monitors and logs detailed user actions and events, including file manipulations, permission modifications, and version rotations
• Provides the ability for team collaboration on documents, spreadsheets, and slides through the integration with Synology Office
• Sends important update notifications via the Synology instant message application Synology Chat
• Backs up Synology Drive to local or remote destinations and restores the settings and data of the package to a previous point in time with the Synology package Hyper Backup

Limitations

• Deleted files from Team Folder will be placed in the Recycle Bin, which is only accessible by system administrators

• Desktop application to synchronize files and folders between the computer and the Synology Drive server to access, browse, and share files via file browser
• Real-time or scheduled computer backup from the local computer to Synology Drive Server with the capability to restore files and folders on the client side

• Synology Drive Server package must be installed on your Synology NAS
• Supported operating systems:
  • Windows 7 and above
  • macOS 10.13 and above (64-bit)
  • Ubuntu 18.04 and above (officially supported versions)

• Create up to 64 sync tasks with Synology Drive Client for Windows environment
• On-demand Sync option to reduce computer capacity consumption and overhead on the server (Available on Windows 10 version 1809 and above)
• File access from file browser on local computer with synchronization with My Drive, Team Folder, and Shared with me folders on Synology Drive Server
• Two-way sync or one-way upload/download to meet different collaboration needs
• Blacklisting file name, file extensions, and maximum file size for each sync task
• Flexible backup settings with continuous, manual, or schedule mode to meet different backup needs
• Monitors and logs file manipulations, including downloads, delete, rename, etc.

• Certain file and drive types are not supported on Synology Drive sync task (Learn more)
• .pst files are not supported because .pst files are not guaranteed to be portable
• Only one backup task can be established for one account
• Folders already synced or folders that are ancestor or child folders to a synced folder cannot be selected for sync task
• If the local folder contains a folder mounted via other file protocols, files inside this mount point might not be synced because Synology Drive cannot detect file changes inside a mount point
• On-demand Sync
  • Local folders which are already synced with Synology Drive's On-demand Sync, OneDrive's File On-Demand, or iCloud Drive and their child folders cannot be selected for a task with On-demand Sync
  • Root drive directories (e.g., C:\ and D:\) and home directories (e.g., C:\Users<username>) cannot be selected as On-demand Sync folder

• Easy access and file management on the go with file searching, sharing, moving, and applying labels in iOS and Android environments
• Granular and flexible file or folder permission settings for secure sharing scenarios 
• Offline access to view the files downloaded to the local device

• Compatible with DSM 6.2.2 or above
• File management with labels, stars, sorting by title, modified time, type, owner, and size
• Content searching with a variety of criteria (e.g., keyword, location, type, owner, labels, size, and date) to quickly gather the most relevant data
• Customizable permission settings to share folders and files only with other DSM users, or share publicly with the protection of password and validity period
• Secure application lock with passcode and 2-step verification if the option has been enabled in DSM
• Offline access and auto-update for multiple files on a local device
• Option to view files in My Drive by file types (e.g., document, photo, video, music)
• Integration with iOS Files and Android document provider as a universal entry to easily browse, open, edit, or move files among different storage apps
• Seamlessly edit files online with Microsoft applications
• Smooth previews and generation of thumbnails of raw images, and support for viewing general file formats (Supported formats may vary by OS and device)
  • Synology Office files: Synology Document, Synology Spreadsheet, Synology Slides
  • Documents: htm, html
  • Images: jpg, jpeg, png, gif, bmp
  • Audio files: mp3, m4a (except for alac), m4b, flac, ogg, wav
• Accelerates file loading speed with cache management

• Synology Slides cannot be viewed if the files are opened with links that do not allow downloads or copies in iOS device

• Photo and video display in chronological order in timeline mode
• Automatic face/special subject recognition in photos with auto-created albums
• Flexible and reliable mobile backup settings
• Synchronization with Synology Drive Server to display photos and videos in My Drive

• Compatible with DSM 6.2.1-23824 and above
• Home service must be enabled first
• The following packages from Package Center must be installed first:
  • Synology Universal Search
  • Synology Application Service
  • Synology Drive Server
• Supported file formats
  • Image formats: BMP, GIF, HEIC, JPEG, PNG, RAW (3fr, arw, cr2, crw, dcr, dng, erf, k25, kdc, mef, mos, mrw, nef, orf, ptx, pef, raf, raw, rw2, sr2, srf ), TIFF
  • Video playback formats: 3G2, 3GP, ASF, AVI, DAT, DivX, FLV, M4V, MOV, MP4, MPEG, MPG, MTS, M2TS, M2T, QT, WMV, XviD
  • Apple's Live Photos playback
  • 360-degree photo and video playback
• AI-calculated features
  • View and edit face recognition results in the People albums
  • View photos categorized by objects and scenes in the Subject album
  • View photos selected by AI aesthetics in the Moments Select section
  • View and decide to keep or delete similar or duplicate photos in the Similar Photos section
  • Choose to apply color and angle adjustments while browsing photos in lightbox mode
• Auto-created albums
  • View the automatically categorized albums: Shared, People, Subjects, Places, Tags, Videos, and Recently Added
  • Enable or disable the People, Subject, and Places albums in Settings
• Photo operations
  • Search photos and albums by keywords, tags, and dates
  • Advanced search by file types, time ranges, tags, or keywords
  • Edit the date, time, and descriptions of photos
  • Add general tags to photos or videos
  • Rotate photos
  • Play slideshows in photo albums
  • Share photos and albums
  • Download albums
• Mobile backup and browsing
  • Back up photos with Wi-Fi/photos only options and duplicated-file handling settings
  • Enhance thumbnail resolution with super-resolution under unstable Internet connections
• Display photos and videos in My Drive
• Shared Photo Library: select specific users to access the shared folder "/photo"

• Drag-and-drop photo upload only allows a maximum of 2,000 photos per upload
• Drag-and-drop folder upload is only supported via Chrome browser
• AI-calculated features are only supported on selected models (Supported models)

• Allows secure and smooth connections from mobile and PC clients to Synology NAS via the Internet without the hassle of setting up port forwarding rules and router configurations
• Creates a readable URL that allows easy file sharing both internally and externally for certain Synology packages

• Ensures server connection efficiency by a LAN/WAN detection mechanism to choose the optimal connection method (Learn more)
• Ensures server reachability by choosing the optimal connection route and the optional QuickConnect relay service
• Secures network connections with end-to-end encryption if SSL is enabled
• Applies required port forwarding rules on compatible UPnP routers automatically
• Customizable permissions for applications to allow access via QuickConnect
• Supports detailed incident records for QuickConnect on the Synology Service Status website (Learn more)
• Supports the following applications and services:
  • DSM
  • SRM
  • Central Management System (CMS)
  • Application Portal
  • Photo Station
  • Moments
  • Audio Station
  • Surveillance Station (including Synology Surveillance Station Client)
  • Download Station
  • Cloud Station (Cloud Station Backup and Cloud Station Drive)
  • Synology Drive Server (including Synology Drive Client)
  • Video Station
  • File Station
  • File Sharing
  • Chat (including Synology Chat Client)
  • Note Station (including Synology Note Station Client)
  • All Synology mobile apps (LiveCam & VPN Plus is excluded)

• Connections to third-party applications are not supported
• Not supported on certain services and packages that require mapping directly to an IP address or a DDNS
• Relayed QuickConnect connections may be slower than connections via port forwarding because of longer network latency
• Relay service might not work because of certain limitations of ISPs in some regions

• Translate the domain name of your Synology NAS to an IP address
• Multiple DDNS providers
• Synology Heartbeat service DDNS server
• Supports custom DDNS provider profiles

• Express Setup: Supports UPnP & NAT-PMP routers
• Advanced Setup: Supports signing in to a router with an admin account
• Supports custom ports for router port-forwarding rules
• Provides router port accessibility test to ensure forwarded ports can be accessed from the Internet

• Tasks can be created to automatically copy files and folders from Synology NAS to attached USB/SD storage devices or vice versa
• Multiple copying and file organizing strategies to provide efficient storage usage and easy backup
• Customized configurations to ensure smooth data exchange

• USB/SD storage devices implemented with file systems recognized by Synology NAS are allowed to copy data (See this article for more information on external devices)
• Copy task types include Photo/Video Import, Data Import, or Data Export
• Multiple methods to initiate data transfer:
  • Hot-plugging a USB/SD device
  • Pushing the hardware Copy button
  • Enabling a schedule
• Flexible copy modes include:
  • Incremental
  • Mirroring
  • Multi-versioned
• Advanced options are available when the incremental copy mode is selected:
  • Remove original file structure in the destination folder
  • File conflict policy
  • Delete source files after copy completes
• Rotation policy options are available when the multi-versioned copy mode is selected:
  • Rotate from the earliest version
  • Smart Recycle
  • Number of versions (Maximum number of versions to keep spans from 1 to 65535)
• Ejects the USB/SD storage device safely and automatically when all related tasks are complete
• File filters to exclude unwanted file types (music, video, image, document) and file extensions from copy tasks
• Logs:
  • Detailed information on each copy task
  • Filter to facilitate searches for logs meeting specified criteria or keywords
  • Maximum number of log spanning from 5 to 100000
• Notifications:
  • SMS
  • Email
  • Mobile
• Beep reminders can be configured for tasks that are starting or completed
• Tasks can be set up for the hardware Copy button

• A partition on a USB device can only support one copy task
• Only one folder can be selected for each copy task
• Ejected USB/SD storage devices have to be re-mounted before new tasks can be created
• Can only be accessed by admin or users belonging to the administrators group
• Only certain models support the hardware Copy button and certain limitations apply (Please refer to this article for more information)