Me and my friend were discussing this the other day about how he said RAID is no longer needed. He said it was due to how big SSDs have gotten and that apparently you can replace sectors within them if a problem occurs which is why having an array is not needed.
I replied with the fact that arrays allow for redundancy that create a faster uptime if there are issues and drive needs to be replaced. And depending on what you are doing, that is more valuable than just doing the new thing. Especially because RAID allows redundancy that can replicate lost data if needed depending on the configuration.
What do you all think?
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
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?