Migration Assistant must be installed on the destination device.
Data and Configuration Migration
Migration scope
Migration Assistant migrates data, system settings, and packages from one Synology storage system to another for storage system upgrades or replacements.
All data and system settings on the destination device are deleted and replaced by the source device data and settings.
Data is migrated on a volume or block-level LUN basis, so the file system type cannot be changed, such as from ext4 to Btrfs.
The destination device keeps its original DSM version and is not rolled back to the source device's DSM version.
Migrated and excluded settings
Migration Assistant migrates all data, packages, and system configurations.
Firewall and DHCP server settings are migrated but disabled on the destination device by default.
The following settings are not migrated: (Learn more)
Synology Account settings
Licenses
Network settings in Control Panel
Server name, default gateway, and IPv6 default gateway in the General tab
Network Interface settings, except VPN profile, IPv6 Tunneling, MTU value in IPv4 settings, and 802.1X
Static Route settings
Push Service settings in Control Panel > Notification
Desktop widget and taskbar settings
Virtual Machine Manager settings
Service Continuity and Performance
Service availability
Services on the source device remain available during most of the migration process.
Services on the source device pause temporarily at the beginning and end of migration.
New changes on the source device are synchronized to the destination device before migration completes.
Migration performance
Migration speed depends on RAID type, network environment, and services running on the source device.
When services run on the source device, migration speed may be reduced to as low as 30 MB/s to preserve source device service quality.
Migration Management
Pause and resume
Migration tasks can be stopped and resumed during migration, including after unexpected power outages or network disconnections.
Logs
Migration logs are available.
Storage creation
Storage pools can be created automatically when the destination device has no storage pool. (Learn more)
Network and system behavior
Ports 7400 through 7499 are reserved for migration.
SSH on the source device is automatically enabled by Migration Assistant after connecting to the source device.
Limitations
Unsupported features
Migration Assistant does not support:
Synology High Availability
MailPlus cluster
Time Backup
Capacity limits
Migration Assistant does not support migrating volumes larger than 200 TB.
Source device restrictions
The following operations cannot be performed on the source device during migration:
When the source device is joined to CMS as a managed server:
Upgrading packages through the CMS host
Applying updated policy rules related to syslog
When the source device is running as a CMS host:
Centrally installing DSM and packages on managed servers
Playing videos with Video Station
Adding download tasks, downloading RSS feeds, or using BT Search in Download Station
Restoring Synology Application Service with Hyper Backup
Destination device restrictions
Resource Monitor on the destination device is unavailable during migration.