The number one mistake people make when migrating from Synology to Unraid is assuming drives can be moved directly between the two systems. They cannot. Synology's volume format is incompatible with Unraid. Any attempt to add Synology-formatted drives to an Unraid array without erasing them first will fail or produce unexpected results. The correct sequence is: back up first, then migrate, then restore. In that order, with verified backups before any hardware change.
In short: You will need an external backup destination large enough to hold all your Synology data (external drive, cloud storage, or a temporary NAS). The migration wipes all drives. Budget 1-3 days of transfer time for large arrays. Unraid hardware can be your existing Synology hardware if it is x86-based (DS920+, DS923+, etc.) or new hardware sourced separately.
Before you begin: Confirm your Synology model uses an Intel x86-64 CPU (DS418play, DS920+, DS923+, and most Plus-series models do). ARM-based J-series Synology units (DS223j, DS423) cannot run Unraid. Check your model's specification page at synology.com before purchasing Unraid or additional hardware.
What You Need Before Starting
| Backup destination | External USB drive or NAS with capacity equal to or greater than your current Synology data |
|---|---|
| Unraid boot drive | A USB flash drive, 4GB minimum; avoid cheap no-name drives. Sandisk, Kingston, or Samsung recommended |
| Unraid licence | Basic ($59 USD, up to 6 drives), Plus ($89 USD, up to 12 drives), or Pro ($129 USD, unlimited) |
| Existing hardware | Your x86-based Synology unit, or new x86 hardware if replacing the NAS entirely |
| Time budget | Allow 8-24 hours for backup transfer on large arrays; do not rush this step |
Step 1: Verify Your Synology Is Compatible
Unraid requires an x86-64 processor. Most Synology Plus-series units (DS420+, DS720+, DS920+, DS923+, DS1522+) use Intel Celeron or Pentium processors and are x86-64 compatible. J-series and some value-series models use ARM processors and cannot run Unraid.
To verify: look up your exact Synology model at synology.com/products. Under CPU specifications, any Intel Celeron, Pentium, Core, or Atom processor is x86-64. Any ARM Cortex-A processor is not compatible with Unraid.
If your Synology uses ARM, you will need to source separate x86-64 hardware for the Unraid build. A budget option is a used Intel NUC, mini PC, or decommissioned desktop with an HBA for drive connectivity. See our homelab hardware sourcing guide for current AU options.
Step 2: Create a Complete Backup
This is the critical step. Do not proceed until you have a verified, complete backup of every file you care about. There is no recovery path if you discover a backup gap after wiping the drives.
Option A: Synology Hyper Backup to external USB drive. Connect a large external USB drive to the Synology. Open Hyper Backup, create a new backup task to the external drive, include all shared folders, and run a full backup. When complete, verify the backup by browsing files through Hyper Backup Explorer. This is the safest method as Hyper Backup includes versioning and integrity checking.
Option B: Direct file copy via File Station or rsync. If you do not use Hyper Backup, connect an external drive and use File Station to copy all shared folders manually. Alternatively, enable SSH on DSM and use rsync from a computer on your network to copy data to a network share or external drive. This method is simpler but does not include Hyper Backup's versioning.
Option C: Cloud backup. If you use Synology Cloud Sync to back up to Backblaze B2, AWS S3, or similar, verify the cloud copy is complete and current before proceeding. Cloud restore to Unraid is slower but works if you lack local backup space.
Verify before you proceed. After backup completes, browse through the destination and confirm files are accessible. Open several files at random. Run Hyper Backup's integrity check if you used Option A. A backup you have not tested is not a backup.
Step 3: Prepare the Unraid Boot Drive
Download the Unraid USB Creator tool from unraid.net. Insert a fresh USB flash drive (4GB minimum; use a quality brand). Run the USB Creator, select your USB drive, and follow the prompts. The tool writes the Unraid boot environment and automatically downloads the latest version of Unraid.
Important: the USB drive Unraid installs to will become your boot device permanently. It does not store data. Its only job is to boot the Unraid OS, which then runs entirely in RAM. Use a reliable USB drive and put it on an internal USB header inside your case rather than an exposed external port where it might be accidentally knocked out.
After writing the boot drive, purchase an Unraid licence at unraid.net before first boot. The licence is tied to the USB drive's GUID, which is assigned when the drive is formatted by the USB Creator.
Step 4: Hardware Setup
If you are reusing your x86 Synology hardware, power it down and remove all drives. Connect the Unraid USB drive to a USB port. If your Synology does not have a USB port accessible from outside (some models do not), you may need to use a screwdriver to access the internal header. Check the iFixit teardown for your specific model to locate internal USB headers.
If you are building on separate x86 hardware (a mini PC, tower, or used server), install the drives from the Synology into the new machine if you intend to wipe and reuse them. If you are sourcing new drives for the Unraid build, install those instead.
Boot from the Unraid USB drive. The Unraid boot menu appears; select the standard boot option. Unraid boots to a CLI that displays its IP address. Access the web GUI by entering that IP address in a browser on your network.
Step 5: Configure the Unraid Array
In the Unraid web GUI, navigate to the Main tab. You will see all attached drives listed as unassigned devices. Assign drives to their roles:
- Parity drive: Assign your largest drive as the parity drive. The parity drive must be equal to or larger than the largest data drive in the array.
- Data drives: Assign remaining drives as data drives. These can be different sizes.
- Cache drive (optional): If you have an SSD, assign it as a cache pool. The cache pool is separate from the array and is used to stage Docker container data and fast temporary storage.
Before starting the array for the first time, enable the Parity check option and set the format to XFS (the recommended filesystem for new Unraid arrays). Then click Start. Unraid will format all drives and write initial parity. For a 4-drive array with 8TB drives, this takes 4-8 hours. Let it complete.
Step 6: Create Shares and Restore Data
Once the parity build is complete, create shares in Unraid that mirror your Synology shared folder structure. Go to Shares and create new shares for each folder you had on Synology (documents, photos, media, backups, etc.). Set the share settings: SMB/NFS enabled, appropriate access permissions.
Now restore your data from backup:
- From Hyper Backup: Install Hyper Backup Explorer on a computer, connect it to your backup destination, and restore files to the Unraid SMB share by mapping it as a network drive.
- From direct file copy: Connect the backup drive and copy files to the Unraid share via File Explorer (Windows) or Finder (Mac) over SMB, or use rsync over SSH for faster transfer.
- From cloud: Set up rclone on Unraid via a Docker container and sync from your cloud provider to the Unraid share.
Transfer speed over SMB to Unraid is typically 90-110 MB/s on gigabit ethernet with a capable CPU. A 4TB restore takes approximately 10-12 hours at full throughput.
Step 7: Install Community Applications and Configure Services
With data restored, install the Community Applications plugin from the Unraid App Store (go to Plugins and install CA App Store). This gives you access to the Docker container library. Search for and install the containers you were running on Synology:
- Plex or Jellyfin for media streaming
- Vaultwarden for password management
- Nextcloud for file sync (if you were using Synology Drive)
- Home Assistant if running on the Synology
Point each container at the appropriate Unraid share for its data directory. Most container templates in Community Applications are pre-configured with sensible defaults and require only the data path and a port assignment.
Common Issues and How to Resolve Them
Drive not showing in Unraid: Check connections and verify the drive shows in BIOS. Some older Synology drives use a 3.3V pin that consumer HBAs misread. Try a different SATA port. If using an HBA card, verify it is supported by Unraid (LSI-based HBAs are the standard recommendation).
SMB shares not visible on network: Check that SMB is enabled in Unraid's Settings and that the workgroup name matches your network. Windows 11 sometimes requires enabling SMBv1 or adjusting the SMB security policy to see older devices.
Slow transfer speeds: Verify gigabit ethernet is active on both the Unraid server and the source computer. Unraid reports network interface speed in the Main tab. If you see 100Mbit instead of 1Gbit, check the cable and switch port.
Plex not finding library: Ensure the Plex container's media library path inside the container maps correctly to the Unraid share path outside it. This is the most common container configuration error and is fixed by correcting the path mapping in the container template.
Australian note on hardware sourcing: If you need additional drives for the Unraid array, IronWolf and WD Red Plus drives are available at Scorptec, Umart, and Mwave with full ACL warranty. For your first Unraid build, stick to new NAS-rated drives from AU retailers rather than eBay SAS drives until you are comfortable with Unraid's drive health monitoring tools. See our homelab power consumption guide to calculate what the new build will cost to run annually.
Related reading: our NAS buyer's guide, our Synology brand guide, and our NAS RAID guide.
Free tools: RAID Calculator and RAID Rebuild Time Estimator. No signup required.
Use our free NAS vs Cloud Migration Cost Calculator to compare the total cost of migrating from cloud to your own NAS.
Related reading: our NAS explainer.
Can I use my Synology drives in Unraid without wiping them?
No. Synology formats drives using Btrfs or EXT4 inside a proprietary volume structure. Unraid does not recognise this format and requires drives to be formatted in XFS, EXT4, or Btrfs in its own volume structure. Any drives moved from Synology to Unraid will be wiped during the Unraid array format process. Back up all data before moving drives.
Can I run Unraid on a J-series Synology NAS?
No. J-series Synology models (DS223j, DS423, DS124) use ARM processors. Unraid requires an x86-64 processor. If your Synology uses an ARM CPU, you will need to source separate x86-64 hardware to run Unraid. The drives from your Synology (once backed up and wiped) can be reused in the Unraid build.
How long does the Unraid parity build take?
Approximately 1 hour per terabyte of parity drive capacity. A single 8TB parity drive takes 7-9 hours to write initial parity. A 12TB parity drive takes 10-14 hours. Run the parity build overnight. The array is usable immediately even before parity is complete, but drive protection only becomes active once parity has been written.
What happens to Synology apps I was using?
Synology first-party apps (Drive, Photos, Surveillance Station, Moments) are DSM-only and cannot be migrated. You will replace them with equivalent Docker containers on Unraid: Nextcloud replaces Synology Drive, Immich or PhotoPrism replaces Synology Photos, Frigate replaces Surveillance Station. The feature parity is good but the migration requires initial setup time and some re-learning of different interfaces.
Do I lose my Synology mobile app connection during migration?
Yes. DS File, DS Photo, DS cam, and other Synology mobile apps connect to DSM. Once you migrate to Unraid, these connections stop working. You will set up alternative access after migration: Nextcloud has official mobile apps, Immich has an excellent iOS and Android app, and most Docker services are accessible via their web interfaces over Tailscale or a Cloudflare tunnel for remote access.
Deciding between Unraid, TrueNAS, and Proxmox for your new build? The full comparison covers what each platform does best.
Read the Full OS Comparison →