I recently got a few (5) hard drives to turn my home server into a NAS with trueNAS scale and my idea is to have 4 usable and 1 for redundancy, my question is… How does RAID work, like what is RAID 0, RAID 5, software RAID etc, and does any of that even matter for my use case?
RAIDz1 is just the ZFS version of RAID5. Since TrueNAS uses ZFS, RAIDz1 is what you’ll be using (or RAIDz2 if you want an additional disk’s worth of redundancy at the cost of a disk’s worth of storage).
RAID5 isn’t applicable to your situation. You’d have to be using a different OS, with a different default file system, for that question to matter.
What’s the difference between RAIDz1 and RAID5? It’s complicated. Without getting into the underlying specifics of how ZFS works, in short they’re two different ways of achieving the same goal. To the end user, the differences are immaterial.
As an aside, if you’re going to be using TrueNAS, which relies on ZFS for its storage technology, you’re going to want to check if your disks use SMR or CMR. See this post for details; https://www.truenas.com/community/threads/WD-SMR-iX-Statement/
smr drives are horrible. we have some here. some by accident, others for cost savings (used only for long term, large file storage)–but all of smr’s faults are really not worth it… maybe at half the price per tb it might be–for some use cases, but not at current pricing.
the last batch we got in don’t even support trim, so i guess the only way to ‘clean up’ zones is to literally dump everything off, secure_erase them, and ‘start over’.
TRIM is SSD technology and SMR is spinning-disk technology, you wouldn’t find them on the same drive, would you? 🤔 Or do you mean a hybrid drive?
