Re: raid1 with several old drives and a big new one

Chris Murphy
2020-07-31T03:36:20Z

On Thu, Jul 30, 2020 at 9:22 PM Eric Wong <e@80x24.org> wrote:
>
> Chris Murphy <lists@colorremedies.com> wrote:

> > When one of the 2TB fails, there's some likelihood that it'll behave
> > like a partially failing device. Some reads and writes will succeed,
> > others won't. So you'll need to be prepared strategy wise what to do.
> > Ideal scenario is a new 4+TB drive, and use 'btrfs replace' to replace
> > the md concat device. Due to the large number of errors possible with
> > the 'btrfs replace' you might want to use -r option.
>
> If I went ahead with btrfs alone and am prepared to lose some
> (not "all") files; could part of the FS remain usable (and the
> rest restorable from slow backups) w/o involving LVM?
>
> I could make metadata (and maybe system chunks?) raid1c3 or even
> raid1c4 since they seem small and important enough with ancient
> HW in play.

Yes. I'm not sure whether it will mount rw,degraded if 2 devices are
missing though, it might insist on read-only.

--
Chris Murphy