this post was submitted on 14 Dec 2023
32 points (84.8% liked)

Selfhosted

40313 readers
253 users here now

A place to share alternatives to popular online services that can be self-hosted without giving up privacy or locking you into a service you don't control.

Rules:

  1. Be civil: we're here to support and learn from one another. Insults won't be tolerated. Flame wars are frowned upon.

  2. No spam posting.

  3. Posts have to be centered around self-hosting. There are other communities for discussing hardware or home computing. If it's not obvious why your post topic revolves around selfhosting, please include details to make it clear.

  4. Don't duplicate the full text of your blog or github here. Just post the link for folks to click.

  5. Submission headline should match the article title (don’t cherry-pick information from the title to fit your agenda).

  6. No trolling.

Resources:

Any issues on the community? Report it using the report flag.

Questions? DM the mods!

founded 1 year ago
MODERATORS
 

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?

you are viewing a single comment's thread
view the rest of the comments
[–] lemmyvore@feddit.nl 11 points 11 months ago (7 children)

If you're using TrueNAS it already has some types of RAID it wants to do. Assuming your 5 drives are the same size what you want is called RAIDz1 (1 standing for one drive worth of redundancy).

It is a type of RAID5, which means instead of having 5x usable storage you reserve 1x for redundancy information spread out across the 5, and get only 4x usable space.

Since you're a beginner you get the usual lecture: RAID is not backup. RAID allows a certain number of your drives to fail without losing any data; it spreads the risk of hardware failure.

RAID won't help if you delete a file or accidentally explicitly format the wrong drive or even the whole array, and won't help if the PC is stolen or struck by lightning or burns in a fire.

The solution used by TrueNAS (ZFS) has something called snapshots that can help with modified or deleted files.

For anything else you have to consider which of your files are "my world has ended"-level of important and backup to a HDD in a drawer, or to Blu Ray discs, or online to the cloud.

[–] Hopfgeist@feddit.de 1 points 11 months ago

To add, unlike "traditional" RAID, ZFS is also a volume manager and can have an arbitrary number of dynamic "partitions" sharing the same storage pool (literally called a "pool" in zfs). It also uses checksumming to determine if data has been corrupted. On redundant setups it will then quietly repair the corrupted parts with the redundant information while reading.

load more comments (6 replies)