Migrating a Proxmox virtual machine using disk passthrough requires special attention.
Unlike standard VM migration, passthrough disks cannot be moved automatically between hosts.
In this guide, you’ll learn how to migrate a Proxmox VM to a new host safely and correctly.
This method is especially important for NAS systems and Synology DSM virtual machines.
We’ll cover how to detach disks, verify disk IDs, and reattach them on the new server.
You’ll also learn common mistakes that can lead to missing disks or data loss.
This tutorial is ideal for homelab users and small production environments.
Follow this step-by-step process to ensure a smooth and reliable VM migration.

Step 1: Shut down the VM

Step 2: Get Disk Passthrough Information

ls -l /dev/disk/by-id/

ata-SAMSUNG_MZ7LN256HAJQ-000L7_S3S7NE0KA13973
Disk passthrough : Samsung

Step 3: Detach Disk Passthrough

Step 4: Backup VM NAS

Back up the VM to another storage (SMB/USB box/Onedrive/NFS…)

Step 5: Restore VM

This demo assumes a vma.zst backup already exists; proceed with the restore.

Step 6: Add Disk Passthrough back and start the VM

qm set 103 -scsi0 /dev/disk/by-id/ata-SAMSUNG_MZ7LN256HAJQ-000L7_S3S7NE0KA13973

Step 7: Add the NFS shared storage again