Break Raid1 array without formatting

Insight & Feedback
1

I set up a Raid1 array with 2x 22TB hard drives thinking that I’d want the redundancy benefits. Turns out, I don’t anymore.

But I already have gone thru loads of steps to set up permissioning properly, with over a TB of (replaceable) files. On the Zima webUI, I see an option to break the raid1 array with a format… I’m assuming this will format both my disks to start fresh. Is it possible to break the Raid1 array without formatting both disks? To turn a Raid1 array into a Raid0, where one of the two disks does get formatted and slapped on as an extra disk, for a total of ~44TB of storage?

2

Breaking a RAID1 array in ZimaOS without wiping everything

Important warning, please read first.

This process can permanently destroy data if the wrong option or disk is selected. If a mistake is made, both drives can be wiped and the array cannot be recovered. I believe this is one of those situations where moving slowly and double-checking every step is essential.

The reality in ZimaOS

Short answer:
No, you cannot convert RAID1 to RAID0 in place, and not without formatting.

Clear explanation:

  • I believe RAID level changes always require a rebuild.
  • The “Break RAID1” option in ZimaOS involves formatting. There is no supported way to convert an existing RAID1 into RAID0 without data loss.
  • ZimaOS uses a managed storage layer, so advanced non-destructive RAID reshaping is not supported.

What is realistically possible

Option 1: Break RAID1 and keep one disk (safest option)

  • I believe ZimaOS can preserve one disk with all data intact.
  • The second disk will be wiped and reused as a standalone disk.
  • Result:
    • Disk A: approximately 22TB with your existing data
    • Disk B: approximately 22TB empty
    • Total usable space is about 44TB as two separate volumes, not RAID0

I suggest this option if your goal is more usable space without redoing permissions and app configuration.

Option 2: True RAID0 as a single 44TB volume

  • Requires backing up all data elsewhere
  • Destroying the RAID1
  • Creating a new RAID0
  • Restoring data

I believe formatting is unavoidable in this scenario.

Safest order of operations in ZimaOS

to reduce the risk of wiping both disks

I suggest not proceeding unless you are confident you can correctly identify each physical disk.

  1. Stop all apps that are using the RAID volume
    This prevents background writes during the change.
  2. Positively identify both disks
    Check serial numbers, not just capacity. Decide in advance which disk you intend to keep. I believe this is the most critical step.
  3. Break the RAID1
    Only proceed if ZimaOS clearly states that one disk will retain the data. If the wording is unclear or implies both disks will be formatted, stop immediately.
  4. Verify the data
    Confirm the retained disk mounts correctly and the files and permissions are intact before continuing.
  5. Initialize the second disk
    Format it as a new standalone disk and add it as a separate storage pool.
  6. Restart apps and reassign storage paths if needed.

Final advice

I believe there is no safe undo once this process starts. If anything in the UI feels ambiguous or rushed, do not continue.