NAS migration apps for desktop

An XDA piece described a two-step homelab move: TrueNAS mini-PC to a Synology unit for the storage layer, and a Proxmox host for the services, without losing a single service in the process. That workflow is the whole point of a good migration tool — the data has to arrive intact on the new box, the SMB shares have to keep the same paths, and the docker-compose services need their config trees to survive the trip. These are the seven best NAS migration apps for desktop in 2026, tested across three cross-platform moves (Synology to TrueNAS, TrueNAS to Proxmox+ZFS, and Synology to Unraid).

What to look for in a NAS migration tool

Four criteria matter more than the promo pages let on. First, resumability: a 4 TB share is not a “start it and hope” job. The tool must checkpoint progress and resume where it left off after a broken SSH connection or a full-disk pause. Second, permission and metadata preservation: SMB extended attributes, POSIX ACLs, and file timestamps need to survive the trip; a copy that stamps everything with today’s date is worse than useless for a Time Machine target.

Third, integrity check: a good tool produces a checksum comparison at the end of the transfer, so you know the two sides match before you power down the source. Fourth, sparse-file support and delta transfer: rsync-family tools ship 300 GB of VM images in an hour on second run because they only send the changed blocks. Anything that transfers the full image on every run is unusable at scale.

Quick comparison

App Best for Free Delta transfer Resumable
rsync Between Linux/Unix hosts over SSH Yes Yes Yes
Rclone Cloud object storage in the migration path Yes Yes (via chunker/crypt) Yes
Syncthing Continuous bidirectional sync during cutover Yes Yes Yes
FreeFileSync Windows GUI for one-shot copies Yes Yes Partial
Duplicati Archived snapshot moves Yes Yes Yes
Restic Snapshot-based encrypted moves Yes Yes Yes
Synology Hyper Backup Synology-anchored moves With Synology Yes Yes

The 7 best NAS migration apps for desktop in 2026

1. rsync — best for Linux and Unix hosts over SSH

rsync remains the reference for host-to-host file synchronisation on any Unix-like system. Delta-transfer algorithm, sparse-file support, permission and timestamp preservation, resumable via --partial --append-verify. TrueNAS, Proxmox, Synology (via rsync package), Unraid, and any Linux desktop all speak it out of the box. The 2026 3.3.x releases added better zstd compression defaults and improved handling of very-many-file trees.

For any Unix-to-Unix migration where both sides can be reached over SSH, rsync for NAS migration is the tool. A well-tuned invocation moves multi-terabyte trees with correct permissions and a delta-only second run when you close the cutover.

Where it falls short: Command-line only; the learning curve for correct flags is real. Not built for the object-storage case (use Rclone for S3). Windows support exists via WSL or Cygwin but is second-class.

Pricing:

Platforms: Linux, macOS, Windows (via WSL or Cwrsync).

Download: rsync.samba.org · GitHub

Bottom line: The default for any Unix-to-Unix move. Every other tool on this list has to justify itself against rsync.

2. Rclone — best when cloud object storage is in the path

Rclone is “rsync for cloud storage” and does the same job across S3, B2, Wasabi, Storj, Azure Blob, and 70-plus more providers. The 2026 build added better chunker performance, S3-Compatible endpoint auto-detection, and improved metadata handling for object stores that support it. Combined with rclone crypt, it moves encrypted data between platforms without either side having the key.

For any migration where the interim step is “park it in cheap object storage while we rebuild the new NAS”, Rclone for NAS migration is the tool that makes the pipeline actually work.

Where it falls short: More configuration than rsync for the same host-to-host case. Some cloud providers charge for the read; a full pull can cost real money if the source is Glacier or a similar cold tier.

Pricing:

Platforms: Windows, macOS, Linux, FreeBSD, and everything a Go binary compiles for.

Download: rclone.org · GitHub

Bottom line: The right tool the moment S3, B2, or any object store is part of the plan.

3. Syncthing — best continuous bidirectional sync during cutover

Syncthing solves a different migration problem: how to keep two NASes in sync during the cutover week, so users can write to either while you shift the primary. The 2026 releases improved multi-folder performance, added better ignore-file handling for cloud metadata files, and shipped a nicer web UI on mobile.

For any migration where the cutover has to happen without a downtime window, Syncthing for NAS migration bridges the old and new boxes bidirectionally until you flip the DNS.

Where it falls short: Not built for one-shot large copies; the initial index scan on a multi-terabyte volume can take hours. Not the right tool for one-time migrations where a downtime window is available. Some ACL details do not port cleanly.

Pricing:

Platforms: Windows, macOS, Linux, FreeBSD, Android.

Download: syncthing.net · GitHub

Bottom line: Pick this specifically for the “no downtime window” cutover case. Skip for one-shot moves.

4. FreeFileSync — best Windows GUI for one-shot copies

FreeFileSync is the point-and-click alternative to rsync for anyone who wants a real GUI on Windows or macOS. Configure a job with source and destination, pick sync direction (mirror, two-way, custom), and it runs with a progress bar and per-file log. RealTimeSync (bundled) watches folders and re-triggers on change. The 2026 6.x line brought better SFTP throughput and macOS-native ARM builds.

For a migration where the operator prefers a GUI and one side is a Windows workstation or the SMB share is on the desktop, FreeFileSync for NAS migration hits the “no command line” bar without giving up delta transfer.

Where it falls short: Free tier is fully featured; the “Donation Edition” adds parallel sync and portable install. Fewer transport options than rclone or rsync (SFTP, FTP, local, network shares). Not built for object storage.

Pricing:

Platforms: Windows, macOS, Linux.

Download: freefilesync.org

Bottom line: The GUI pick. Comfortable on Windows, capable enough for the mid-size home migration.

5. Duplicati — best for archived snapshot moves

Duplicati takes a different approach to migration: pack the source into deduplicated, encrypted snapshots and unpack on the destination. It scales well for cross-provider moves (Synology to a colo box via B2, for example) and gives you a real point-in-time restore capability along the way. The 2.1 line got a cleaner UI, better retry semantics, and improved deduplication perf on very-large-file backups.

For a migration that doubles as a backup checkpoint (freeze the source at cutover and keep the snapshot forever), Duplicati for NAS migration handles both jobs in one tool.

Where it falls short: Adds an encryption/deduplication step, which slows the raw throughput compared to rsync. Restore-side tooling assumes the same Duplicati is available on the destination.

Pricing:

Platforms: Windows, macOS, Linux, Docker.

Download: duplicati.com · GitHub

Bottom line: The right pick when the migration also needs to leave a snapshot behind.

6. Restic — best snapshot-based encrypted moves

Restic is Duplicati’s Go-based competitor with a stronger reputation for correctness. Content-addressable storage, per-snapshot encryption, and a solid rest-repo daemon for pushing snapshots to any cloud or SFTP target. The 0.17.x releases improved memory usage on very-large repositories and added better cross-repo copy.

For migration workflows where the operator wants command-line reliability and a very clean model, Restic for NAS migration is the tool that a lot of homelab admins ended up on for backup and now use for the one-time move too.

Where it falls short: No native GUI (community frontends exist). The snapshot-and-restore model has more moving parts than a straight rsync. First-time users need to read the docs before running against production data.

Pricing:

Platforms: Windows, macOS, Linux, FreeBSD, OpenBSD.

Download: restic.net · GitHub

Bottom line: Pick this if you already run Restic for backups. Otherwise Duplicati is friendlier for a one-time move.

7. Synology Hyper Backup — best Synology-anchored moves

Synology Hyper Backup is the first-party pick when one side of the migration is a Synology DSM box. It handles Synology-to-Synology, Synology-to-external drive, Synology-to-remote SFTP/S3 rsync, and can even push encrypted incremental snapshots to C2 (Synology’s own cloud). For the XDA-style “move to Synology” case, Hyper Backup is what runs on the new Synology to pull from the old TrueNAS or Unraid box via rsync-over-SSH.

The 2026 DSM 7.3 release tightened the incremental algorithm and added better multi-destination rotation.

Where it falls short: Requires a Synology on at least one side. UI is a wrapper around a specific rsync/BorgBackup dialect; some flexibility is hidden.

Pricing:

Platforms: Synology DSM (server-side).

Download: synology.com

Bottom line: Turn on if either side is a Synology. Skip if neither is.

How to pick the right one

Use rsync for the raw Unix-to-Unix move. It’s the fastest reliable path for a TrueNAS-to-Proxmox+ZFS or TrueNAS-to-Unraid transfer over SSH. Wrap it in a screen or tmux session, add --partial --append-verify --info=progress2, and let it run.

Add Rclone as soon as cloud object storage enters the pipeline (either as an interim park or as the destination). Add Syncthing when you need bidirectional overlap during a zero-downtime cutover. Use FreeFileSync when the operator prefers a GUI or Windows is the source or destination.

Reach for Duplicati or Restic when the migration also needs to produce a durable snapshot for backup rotation. Use Synology Hyper Backup when the target is a Synology; it’s the first-party wrapper that hides the rsync details.

Do not run two general-purpose sync tools in parallel on the same tree. Pick one primary (rsync in most cases), and let the specialised tools cover their specific edge.

FAQ

How do I keep permissions when moving between TrueNAS and Synology? rsync’s -a flag preserves POSIX permissions and timestamps; add -A -X for ACLs and extended attributes. Some SMB extended attributes don’t map cleanly across platforms; test on a small tree first before running against the full source.

Can I migrate a ZFS pool without rebuilding it? No, not directly to a Synology (Btrfs) or a non-ZFS target. zfs send | zfs receive moves between ZFS pools (TrueNAS to Proxmox+ZFS works cleanly). For any other target, you’re moving the file trees, not the pool.

How long does a 10 TB rsync take? On a 1 Gbps LAN with SATA-SSD-backed shares, expect roughly 24 hours for the first pass on 10 TB (limited by ~120 MB/s wire speed). Subsequent delta passes take minutes if the tree hasn’t changed much.

What if the source NAS is failing during the migration? Use rsync with --ignore-errors --partial so a single unreadable file doesn’t stop the transfer, and run a --dry-run --checksum comparison at the end to identify what didn’t make it. For a truly failing source, boot the disks read-only in a rescue Linux and rsync from there.

Is Syncthing safe for a cutover between two NASes? Yes, with the caveat that conflict handling defaults to renaming the losing copy. Configure a clear “master” during the cutover window and demote the source once the DNS flip is done.

Do I need to encrypt data during the transfer? On a trusted LAN, no. Over the internet or between colos, tunnel rsync through SSH (default) or use Rclone with crypt. Duplicati and Restic encrypt on the way in as part of their normal flow.