Existing-drive migration
HDD migration physically moves the existing Synology drive set into a compatible destination NAS. It can minimize downtime and avoid buying a second full set of disks, but it carries stricter limitations because the destination inherits the existing storage pool, volume settings and filesystem. Synology’s current migration documentation also warns about model and package-architecture compatibility.
Quick answer
HDD migration is convenient only when the pairing is truly supported
Do not assume that moving the trays into a newer NAS will preserve every package and setting. Check model families, DSM version and package architecture first.
Current Amazon listings
Replacement and migration DiskStation options
Product cards are supporting purchase references only; they do not determine whether your failed drives are recoverable or whether a specific migration pairing is supported.
Technical decision
The old drives remain the production data during the move
That makes a verified independent backup essential. A mistaken compatibility assumption can turn an upgrade into a recovery project.
Interactive recovery tool
Synology Migration Method Selector
This tool routes the symptoms you select to a safer next step. It does not issue destructive commands. Before initializing a disk, deleting a pool, reinstalling DSM or moving the only copy of important data, verify the exact live Synology procedure for your model and DSM build.
Recovery safety checklist
Four rules before you change a failing Synology system
Preserve readable data first
If unique files can still be opened, copy or back them up before changing storage metadata, reinstalling DSM or running stressful diagnostics.
Record drives and bays
Capture drive serial numbers, bay positions, health states and DSM messages before swapping disks or moving them to another chassis.
Match the action to the failure layer
A degraded pool, crashed volume, failed system partition, bad drive and failed bay have different supported recovery paths.
Keep a rollback path
During migration or recovery, do not erase the source system until the destination data, permissions, applications and backups have been verified.
HDD migration physically transfers the source array
You shut down the source, move the existing drive set into the destination in the required order and allow DSM to recognize the migration state. The process is fast because terabytes do not need to cross the network.
For HDD migration, hdd migration physically transfers the source array must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
The storage layout comes with the drives
RAID type, storage-pool structure, volume configuration and filesystem remain tied to the existing disks. HDD migration is not the method to choose when the goal is redesigning the storage architecture.
For HDD migration, the storage layout comes with the drives must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Single-bay and multi-bay moves have restrictions
Synology documents model-class limitations, including restrictions between some single-bay and multi-bay systems. Check the exact migration table rather than relying on bay count alone.
For HDD migration, single-bay and multi-bay moves have restrictions must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Package architecture can change the result
Older processor architectures may migrate only to systems with the same package architecture without losing DSM configuration and package settings. User data may survive while the software environment does not.
For HDD migration, package architecture can change the result must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Destination DSM support matters
The destination must support the DSM version retained after HDD migration. A newer chassis does not guarantee every historical DSM build or package stack is supported.
For HDD migration, destination dsm support matters must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Drive compatibility should be checked before shutdown
Existing disks accepted by the source NAS may have a different support or warning status on the destination. Review Synology’s current compatibility policy for the exact destination model before relying on those drives.
For HDD migration, drive compatibility should be checked before shutdown must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Preserve drive order and labels
Photograph and label each source bay before removal. Insert drives into the destination in the same sequence where the migration instructions require it, and do not mix the set with new blank drives until the migration state is understood.
For HDD migration, preserve drive order and labels must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Do not initialize drives that should show migration
If the destination offers to create a new pool instead of identifying the existing migration, stop. Initialization can overwrite metadata and eliminate the simpler rollback path.
For HDD migration, do not initialize drives that should show migration must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
A backup is still mandatory
HDD migration saves time but does not create a second copy. If the old drives are the only dataset, a chassis or compatibility problem during migration can leave you with no clean fallback.
For HDD migration, a backup is still mandatory must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Use Hyper Backup when you need structural change
If you want to move from ext4 to Btrfs, redesign RAID, reduce legacy baggage or selectively restore packages, backup-and-restore may take longer but creates a cleaner destination.
For HDD migration, use hyper backup when you need structural change must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Test applications after the new chassis boots
Even when DSM and shares appear normally, confirm databases, Docker/Container Manager projects, surveillance workloads, certificates and scheduled backups. Hardware architecture changes can expose package-specific issues.
For HDD migration, test applications after the new chassis boots must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Keep the source chassis available temporarily
Do not sell or discard the old enclosure until the destination is stable and backed up. The source chassis may be useful if rollback or additional recovery from the original drive set becomes necessary.
For HDD migration, keep the source chassis available temporarily must respect that the existing drive set carries the old pool, filesystem and much of the system state into the destination. Verify model class, package architecture, DSM support and drive compatibility before the source is powered down. Label every disk so the original arrangement remains reconstructable. This checkpoint should prevent the speed of a physical drive move from hiding its main limitation: the method preserves legacy storage structure and therefore offers much less redesign freedom than a backup-and-restore migration.
Questions people ask
Synology HDD Migration Guide questions
What is Synology HDD migration?
It is the process of moving the existing source NAS drives into a compatible destination Synology NAS while retaining the storage layout.
HDD migration is appropriate only when the exact model path is supported and keeping the existing drives and storage layout is genuinely the goal.
Can I change RAID type during HDD migration?
No. The existing storage-pool and volume settings remain with the drives. Use another migration method if you want a new layout.
Can I change from ext4 to Btrfs?
Not through HDD migration. Hyper Backup is the more flexible path when changing filesystem.
Do I need to preserve drive order?
Yes. Record bay order and follow the exact Synology instructions for the source and destination.
Can I migrate from any Synology to any other Synology?
No. Model and package-architecture limitations apply.
Will all my packages survive?
Not always. Incompatible architectures can cause configuration and package settings to be lost even if user data remains.
Should I check drive compatibility on the destination?
Yes. The destination model's current compatibility policy determines whether the reused drives are supported or warned.
What if the destination wants to initialize the drives?
Stop before accepting initialization. Confirm that the model pairing and migration procedure are correct.
Is HDD migration safer than Migration Assistant?
It is faster and uses the same drives, but it has less structural flexibility and leaves you dependent on the original disk set during the move.
Do I still need a backup?
Absolutely. HDD migration is not a backup and should not be attempted with irreplaceable data existing only on the moved drives.
Official references and methodology
Verify the live DSM state before any destructive recovery step
This HDD-migration guide focuses on the consequences of physically moving the existing drive set into another Synology NAS. It verifies model/architecture compatibility, DSM expectations, drive acceptance, bay order and the availability of a separate backup before shutdown. Because the method carries the source storage layout into the destination, it is treated as a continuity option rather than a clean opportunity to redesign the pool or filesystem.
- Synology: HDD migration guide
- Synology: Migration methods between Synology NAS systems
- Synology: Determine whether errors come from the drive or slot
As an Amazon Associate, Cloudzat may earn from qualifying purchases. Failure states, DSM behavior, migration compatibility and recovery options can change by model and DSM build. Preserve readable data and verify Synology's current Knowledge Center instructions before initializing drives, deleting pools, reinstalling DSM or changing the only copy of important data.