Raid1 disk replacement, for greater capacity - Sostituzione dischi Raid1, per maggiore capacità

Operating System ZimaOS
1

English > I’ve been following the home NAS project for a while now and have built my own NAS using a salvaged PC.

I can’t find any information on how to replace my two 500GB drives (used for other storage) and upgrade to two 4TB drives.

The 500GB drives are currently in RAID 1. How do you recommend I proceed to get two larger capacity drives?

Thanks

Italiano > È da un po’ che seguo il progetto Nas casalingo e mi sono autocostruito un nas con un PC di recupero.

Non trovo informazioni in merito a come possa sostituire i miei due dischi entrambi da 500gb (usati per il resto) e passare a due dischi da 4Tb?

Al momento i dischi da 500 GB sono in Raid1, come mi consigliate di procedere per avere due dischi di capacità maggiore?

Grazie

2

Good question, upgrading from 2 x 500GB (RAID1) to 2 x 4TB (RAID1) is a very common upgrade path.

Quick note (English post)

If possible, could you please repost your question in English (you can paste the translation above)?
That way more people can help you, and it helps others later when they search the forum. Thank you

Can RAID1 be upgraded in ZimaOS?

Yes and no — it depends how your RAID1 was created in ZimaOS.

  • If it’s a standard Linux RAID1 (mdadm) then normally you can replace disks one at a time, allow rebuild, then expand.
  • But if it was created using the ZimaOS storage UI/pool, it may not support disk replacement + expansion, depending on your ZimaOS version and hardware.

So the safest advice is:

Safest method (recommended)

  1. Backup your data first (RAID is not a backup)
  2. Remove the old RAID1 / delete the pool
  3. Install the 2 new 4TB drives
  4. Create a new RAID1 with the two 4TB drives
  5. Restore your data from backup

This method always works and avoids any chance of RAID rebuild/resize issues.

If you want to check if upgrade-in-place is possible

Post the output of:

  • lsblk
  • cat /proc/mdstat

…and we can confirm whether your RAID is mdadm (upgrade possible) or ZimaOS pool (likely rebuild needed).

3

I ran Raid1 using ZimaOS. Since mine is currently a test bench, I could reinstall the operating system from scratch (a clean install) and connect the new 4TB HDDs. I don’t know Linux and I don’t know how to create an mdamd raid. If it’s not complicated for a Linux newbie like me, I could try. Otherwise, I use ZimaOS’s pool. I hope that in the future, when the 4TB Raid1 is full, I won’t have to go crazy trying to increase the capacity.

Grazie

4

Hi MicheleF, thanks for the update mate

And yes, if this is still a test bench, doing a clean reinstall + new 4TB pool is actually the safest and easiest path. That’s a really smart approach.

Your options (newbie-friendly)

Option A (Recommended): Clean install + create new ZimaOS pool

Since you don’t know Linux/mdadm yet, I’d stick with this:

  1. Backup anything important
  2. Fresh install ZimaOS
  3. Install the 2 x 4TB drives
  4. Create a new RAID1 pool using the ZimaOS storage UI

This is the easiest and most reliable way for beginners.

Option B: mdadm RAID1 (possible, but not required)

Yes, mdadm RAID1 is possible, but honestly don’t force yourself into it yet.

ZimaOS is designed so users don’t have to manage mdadm manually, and the ZimaOS pool option is the right choice for most people.

About future upgrades (when 4TB becomes full)

This is the important part:

Right now, ZimaOS RAID/pool expansion and “replace disks to grow RAID1” is not always guaranteed (depends on ZimaOS version and storage implementation).

So the best mindset is:

  • RAID1 gives redundancy
  • But upgrades later may still require:
    • backup
    • rebuild pool with larger drives
    • restore data

That’s normal even on many NAS systems.

The best protection: keep a proper backup strategy (USB or cloud).

Short best practice plan (so you never “go crazy” later :grinning_face_with_smiling_eyes:)

1) Keep OS separate from data

  • Install ZimaOS on a small SSD/NVMe (even 128GB is fine)
  • Use your RAID1 pool only for storage/data

This avoids the OS drive filling up and breaking updates/apps.

2) Keep AppData / Docker on a non-RAID disk (if possible)

If you run lots of apps/containers:

  • Put AppData/Docker on a dedicated SSD
  • Keep the RAID1 pool mainly for media/files/backups

This makes performance much better and makes recovery easy.

3) Always have 1 external backup

RAID is not backup.

  • USB HDD, another NAS, or cloud backup
  • Even a small backup is better than none

4) Plan upgrades early

When you reach about 70-80% storage full, start planning the next upgrade.
That gives you time to migrate safely without stress.