From: Wols Lists <antlists@youngman.org.uk>
To: Ram Ramesh <rramesh2400@gmail.com>,
Reindl Harald <h.reindl@thelounge.net>,
Linux Raid <linux-raid@vger.kernel.org>
Subject: Re: Is it possible to break one full RAID-1 to two degraded RAID-1?
Date: Fri, 7 Feb 2020 09:27:56 +0000 [thread overview]
Message-ID: <5E3D2D9C.8020908@youngman.org.uk> (raw)
In-Reply-To: <0c70c04f-d8d0-0c44-e603-46c101b21cc1@gmail.com>
On 07/02/20 07:02, Ram Ramesh wrote:
> I got no response on this and want to take a shot before going the
> backup way.
>
> Assuming (hda1 and hdb1 in raid1 md0) Will the following work?
>
> 1. Fail and remove hdb1
> 2. Create new RAID1 md1 with hdb1 and missing
> 3. dd md0 onto md1
I wouldn't bother with any of the above. Just shut down and physically
remove a LIVE disk. That now is your backup.
In fact, this might be a good excuse to get a 3rd disk and either go
raid 5 or use it for backups.
> 4. Make both bootable. (I suppose I need to change UUID of md1
> partitions. I suppose that is easy)
Yes it's easy. Yes it should have been done a LOOONG time ago.
> 5. Boot both and double check
They'll be degraded, so you might have to do a forced assembly to make
them run ...
> 6. Now upgrade md0 without fear.
> 7. Boot and test the new system for a couple of days to make sure
> everything is fine.
> 8. If that fails, delete md0, and add hda1 to md1. If not delete md1
> and add hdb1 to md0
Yup.
>
> Regards
> Ramesh
>
Cheers,
Wol
next prev parent reply other threads:[~2020-02-07 9:27 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-29 3:17 Is it possible to break one full RAID-1 to two degraded RAID-1? Ram Ramesh
2020-01-29 4:09 ` Reindl Harald
2020-01-29 22:32 ` Ram Ramesh
2020-01-30 6:30 ` Reindl Harald
2020-01-30 7:27 ` Wols Lists
2020-02-07 7:02 ` Ram Ramesh
2020-02-07 9:27 ` Wols Lists [this message]
2020-02-07 14:49 ` Ram Ramesh
2020-02-07 14:55 ` Reindl Harald
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