Hi, a complete newbie to the HomeLab/NAS scene and I am just in the process of setting up a Mini PC, with 4 x 2TB M.2 NVME and 1 x 512GB M.2 NVME and will be using ZimaOS with the *arrs, Emby, Immich and Nextcloud primarily.
Anyhoo, my question is with regards to the 512GB NVME that will be where the OS will be installed. I understand that the 4 x 2TB drives have some safeguards when set up as Raid 5, but what about the OS drive? Is there a built in backup or clone feature? I would like to do a periodic baclup or clone onto an external drive but would this actually work? If the OS drive failed and I didn’t have a cloned drive to replace it, then i’m guessing a reinstall of the OS would mean difficulty in keeping the already created Raid drives?
I’ve probably gone all around the houses trying to explain myself, but i’m basically concerned about what would happen to the data on the Raid drives should the OS drive fail?
Usually you need run backups of the OS drive either from external media, or using software that can snapshot the drive and save the snapshot. If the OS drive is “doing stuff” between the time the backup start and end its possible your backup will not work as a restore.
The data on the RAID drives should be secure, and once you re-install the RAID software it should see the existing raid and work, but It may be best for others to confirm that as I use mine as separate drives not a RAID array.
You’re thinking about exactly the right thing before you load up *arrs, Emby, Immich, and Nextcloud. In ZimaOS the OS lives on your 512 GB NVMe, while your actual data and app configs live on the storage pool (your 4×2 TB). They’re deliberately separated: the pool sits under /DATA, so if the OS drive ever dies you don’t lose the array. You just install ZimaOS on a replacement SSD, boot, and your pool is still there.
The one little file I always keep a copy of is the pool layout database: local-storage.db. You can grab it from /ZimaOS-HD/.casaos/db and stash it somewhere safe. If you ever reinstall, drop it back in the same place and reboot—ZimaOS will “remember” your pool instantly. For apps, all the persistent bits live under /DATA/AppData/… (and your media under something like /DATA/Media). After a clean OS reinstall, reinstall the apps and point them to those existing folders; they pick up where they left off.
On cloning vs backup: cloning the OS SSD works, but it’s usually overkill. The system partitions are small and easy to recover. What really matters is backing up your data in /DATA (USB disk, another NAS, or cloud—the usual 3-2-1 idea). If the OS SSD fails, the recovery path is simple: new SSD > reinstall ZimaOS > restore local-storage.db > reinstall apps > point them at your existing /DATA paths. Your RAID and files stay intact the whole time.
So, bottom line: an OS-drive failure doesn’t endanger the RAID pool, and you won’t be starting from scratch as long as you’ve kept that tiny DB and your /DATA backups in order.
For anyone who wants the official, step-by-step playbook: all the recovery and rebuild details live in ZimaSpace’s docs—use the System Quick Recovery Guide for slot-A/slot-B boot recovery and quick rollbacks (ZimaOS System Quick Recovery Guide | Zimaspace Docs
), and the Rebuilding RAID after reinstalling the system guide for restoring your pool with local-storage.db after a fresh OS install (Rebuilding RAID after reinstalling the system | Zimaspace Docs
).