71
Is RAID still needed?
(programming.dev)
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 05 Apr 2024
71 points (97.3% liked)
Asklemmy
43974 readers
627 users here now
A loosely moderated place to ask open-ended questions
Search asklemmy ๐
If your post meets the following criteria, it's welcome here!
- Open-ended question
- Not offensive: at this point, we do not have the bandwidth to moderate overtly political discussions. Assume best intent and be excellent to each other.
- Not regarding using or support for Lemmy: context, see the list of support communities and tools for finding communities below
- Not ad nauseam inducing: please make sure it is a question that would be new to most members
- An actual topic of discussion
Looking for support?
Looking for a community?
- Lemmyverse: community search
- sub.rehab: maps old subreddits to fediverse options, marks official as such
- !lemmy411@lemmy.ca: a community for finding communities
~Icon~ ~by~ ~@Double_A@discuss.tchncs.de~
founded 5 years ago
MODERATORS
I'd say "old" RAID could be dead if you have proper backups and have the ability to replace a defect drive fast in the case uptime is crucial. But there's also modern RAID like btrfs and zfs that also can repair corrupted filed, caused by bitrot for example. Old RAID can't do that also hardware based RAID couldn't either when I used it until years ago. Maybe that changed but I don't see the point of hardware based RAID in most cases anymore
Hardware raid can 100% do any of the above tasks, and has always been able to do them. You need an actual raid card, not some half assed baked in mobo raid.
Hardware RAID was doing all of the above before software RAID was available to end users.
But AFAIK real RAID don't perform CRC, thy rely on drive to report bad sector. In case if on one drive data got corrupted, it would return data from one drive or another. In case of mirroring. If we aren't talking about RAID 6 I think.
I wonder how to detect real raid card from simple switch? I guess to look at price and it should be really high?
Most discrete raid cards will do the job, but look for on card caching and a battery for "quality."
RAID and backups serve different purposes. Backups are to prevent data loss, RAID is to prevent downtime in case of hardware failure. They are not interchangeable.
Different purposes true, but not exclusively. RAID only has effect on drive failure specifically. If downtime is intolerable then it's not the right solution to just use RAID and you should look into total redundancy of the hardware and more. It also comes with performance bottlenecks or improvements depending on the setup, that's another factor to take into account. So in the end it really depends on your requirements and backups can actually serve as an alternative, depending on your setup and as long as it meets your RTO
AFAIK only officially supported RAID modes in BTRFS are RAID0 and RAID1.
RAID56 is officially considered unstable.
Raid56 is a risky one in more filesystem than just btrfd though, but if you have a ups as backup, you should be fine.
UPS won't protect from Kernel Panic, sadly
True
What about dm-raid? Is it still risky? I guess so, because it's separate devices. So any software raid with 5-6 would be problematic?