6.11.5 - Requesting a sanity check on my drive migration plan

[FoxxMD]

I've recently added new drives to my machine and have an end-goal for them. I'm looking for more eyes on my migration plan to get these drives into the array and hoping for confirmation/feedback that I'm doing this right/avoiding unnecessary risk/rebuilds.

 

All unassigned drives have been pre-cleared.

• WDC_92U1 - 14TB - sdl

• WDC_UVHC - 14TB - sdm

• WDC_8YLD - 6TB - sdf

 

Current array

 

 

Goals

• Replace Parity 1 with larger drive
  • Replace Parity 1 8TB - sde Parity 1
  • with unassigned WDC_92U1 - 14TB - sdl
• Add 14TB Data
  • Add unassigned WDC_UVHC - 14TB - sdm
• Replace slowly dying data drive
  • Replace Disk 1 (4TB - sdi)
  • with unassigned WDC_8YLD - 6TB - sdf
• Add old 8TB - sde (old parity 1) as Data drive

 

Using the steps below I believe I should be able to achieve this without losing parity protections and only incurring two parity rebuilds.

Steps

1. Add 14TB Parity

Parity disks do not need to be the same size but all need to be as large as the largest data disk. By adding as second parity I maintain array protection while rebuild is occurring and have additional protection during subsequent operations.

 

Using directions from docs:

• Stop array
• Add WDC_92U1 - 14TB - sdl as Parity 2
• Start array, wait for rebuild to finish

2. Replace 4TB slowly dying data drive

Disk 1 shows error count in "array devices" but the disk is still green and my last parity check (10 days ago) finished with zero errors. Error count after 10 days is 469. It's been like this for the last couple of months and parity checks always finish without error.

 

I think I should be OK to replace this directly with a new (larger) drive WDC_8YLD - 6TB - sdf. Additionally, I'll have two parity disks during this operation so "doubly" protected.

 

Using directions from docs:

• Stop array
• Unassign Disk 1 - MB4000GDUPB_16PHK26MF17A - 4 TB (sdi)

• Start array to get unraid to present disk as emulated (normal or maintenance?)

• Stop array

• Assign new drive WDC_8YLD - 6TB - sdf as Disk 1

• Start array, wait for rebuild to finish

3. Remove 8TB Parity

In order to use the second 14TB data drive the parity drive(s) must be as large as it is. So I need to remove 8TB - sde parity.

 

Using directions from docs:

• Stop array

• Set Parity 1 (WDC_WD80EMAZ-00WJTA02YJHNBPD - 8 TB - sde) to Unassigned

• Start array

4. Add remaining data drives

• Pre-clear old parity drive WDC_WD80EMAZ-00WJTA02YJHNBPD - 8 TB - sde

• Stop array

  • Add unassigned WDC_WD80EMAZ-00WJTA02YJHNBPD - 8 TB - sde as data

  • Add unassigned WDC_WUH721414ALE6L1_Y6GKUVHC - 14TB - sdm as data

 

________

 

How does my plan look? Is it sound? Do I understand the order of operations correctly? Thanks

Edited November 14, 2023 by FoxxMD

[JonathanM]

Sounds good to me, you will be stuck with parity2, since they aren't equivalent. If that doesn't bother you, fine, it will work just fine with nothing assigned to parity1.

 

When replacing a drive, no need to start the array with the old device unassigned, that's only needed if you plan on rebuilding to the same drive. Just power down, physically swap the drives, then before you start the array assign the replacement drive.