Hi everyone,

I'm planning to remove a data disk from my array using the parity-preserve method and want to validate my procedure before proceeding.

I'll be doing a physical disk swap (not just logical reassignment).

Current situation:

• Unraid 7.1.4

• disk11 (10TB) needs to be removed

• I have a spare 20TB drive (already zeroed via Unassigned Devices) to replace it

• All data from disk11 will be moved to other disks first

• All drives are healthy

My planned procedure:

Phase 1: Data Migration

1. Move all data from disk11 to other array disks

2. Verify disk11 is completely empty du -sh /mnt/disk11)

Phase 2: Zeroing disk11 (Official method)

1. Stop array

2. Start array in Maintenance Mode → Click disk11 → Erase button → Stop array

3. Start array in Normal Mode (disk11 won't mount but stays in array)

4. Identify disk11 device: check Main → disk11 → "Device" field

5. Zero out the disk: dd if=/dev/zero of=/dev/sdX bs=1M status=progress

6. Wait for completion

Phase 3: Physical Swap

1. Stop array

2. Shutdown Unraid

3. Physically remove disk11 (10TB)

4. Connect spare drive (20TB) to the same SATA port

5. Boot Unraid

Phase 4: New Config & Reassignment

1. Do NOT start array

2. Tools → New Config (Preserve current assignments ?)

3. Check both:

- ✓ "Yes, I want to do this"

- ✓ "Parity is already valid"

4. Apply

5. Main → Reassign ALL drives:

- Parity disk → same as before (critical!)

- disk1-disk10, disk12+ → same assignments

- disk11 → new 20TB drive

6. Triple-check parity disk assignment

7. Verify "Parity is already valid" is still checked

8. Start array

My questions:

1. Is this procedure correct for a physical disk swap?

2. Since I zeroed the 20TB spare via Unassigned Devices (outside the array), and disk11 will be zeroed using the official method (inside the array), will "Parity is already valid" work correctly?

3. Do I need to do anything specific because I'm upgrading from 10TB to 20TB in the same slot?

I'm following the official documentation here:

https://docs.unraid.net/unraid-os/using-unraid-to/manage-storage/array-configuration/#removing-data-disks (Parity-preserve method - Advanced)

But the doc doesn't explicitly cover the physical swap scenario with a pre-zeroed replacement drive.

Thanks in advance for your help!

51 minutes ago, Arturia said:

1. Is this procedure correct for a physical disk swap?

2. Since I zeroed the 20TB spare via Unassigned Devices (outside the array), and disk11 will be zeroed using the official method (inside the array), will "Parity is already valid" work correctly?

Yes, if the new disk has been precleared.

52 minutes ago, Arturia said:

3. Do I need to do anything specific because I'm upgrading from 10TB to 20TB in the same slot?

Nope

Okay thanks :)