I'm planning to build my own NAS and now decide to use Unraid instead of TrueNAS because ECC memory will be important to ZFS compared to other filesystems. (I saw this from a lot of discussions)
My question is why? I know ZFS rely on RAM for caching, but why ZFS is more vulnerable to memory corruptions? And why other systems like unraid and btrfs are not as emphasize ECC memory?
It's quite interesting to see two major voices. People from TrueNAS side suggest you must have ECC memory if you care about your data. But people from unraid side said ECC it's not worth the money.
----
I also think if I keep a list of hashes when I back up my data, then ECC might not be nessary at all.
@skyblond ECC is generally recommended in a RAID setup because it (usually) prevents corrupt data to be written to the disk. Regardless of the filesystem.
Think of ECC like disc brakes. You don't need disc brakes on a slow moving vehicle. Similarly, on a machines that handles a lot of data, you want ECC RAM to prevent data corruption.
If you maintain hashes of file written, you can get by with any setup. Make sure you have 3 copies of hashes and hash of the file containing hash itself.
@thefossguy Thanks for the answer! I think I'll stick with consumer hardware without ECC to bring the overall cost down. But I do plan to have backups following the 321 rule, along with hashes to ensure the backup is not corrupted silently.
