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From:   Torsten Bronger <bronger@physik.rwth-aachen.de>
Subject: Re: Why is converting from RAID1 to single in Btrfs an I/O-intensive operation?
Date:   Sat, 18 Feb 2023 21:05:48 +0100
Organization: Phoenix Foundation
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Hallöchen!

me@jse.io writes:

> On Sat, Feb 18, 2023 at 7:45 AM Torsten Bronger
> <bronger@physik.rwth-aachen.de> wrote:
>>
>> [...]
>>
>> I agree that converting to single is not the fastest way to
>> replace a disk, but the safest AFAICS.  It is the boot partition
>> in a simple home server without monitor or keyboard, which makes
>> mounting as degraded difficult.  Besides, you can only mount in
>> degraded mode once.  If anything goes wrong, I have to rebuild
>> from scratch.
>
> I just want to make clear, this bug was fixed long ago. You would
> need to update your bootloader conf to use degraded at boot time
> in this case, but in theory, it should work identical to have a
> raid1 degraded as converting it all back to single.

What was fixed?  Can you now mount in in degraded mode read-write as
often as you wish?

Regards,
Torsten.
-- 
Torsten Bronger