ZFS recovery - QNAP and TrueNAS

Preparing source disks

The first step is to remove the disks from the NAS and connect them to the PC for recovery.

• You must connect all the disks simultaneously unless you are recovering an Unraid system. If at all possible, avoid using USB-to-SATA adapters. Use regular SATA connections instead.
• When removing disks from the NAS, make sure to label the disks and their corresponding bays. While all NASes I know recognize the array if you shuffle the disks, the labels may be helpful later for other purposes (e.g., troubleshooting a faulty drive bay).

Once the disks are connected, it is prudent to examine the SMART status of all the disks. You should then make clones or images of any disks that have reallocated sectors, pending sectors, or look otherwise disagreeable.

Preparing target storage

You need a storage device with enough free space to fit all the data you want to recover. It can be a direct-attached SATA drive, a direct-attached RAID array, or a network share. Refer to this page if you plan to recover onto a network share. While USB drives tend to work better as a target than as a source, I still recommend using SATA instead of USB whenever possible.