All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nix <nix@esperi.org.uk>
To: Leslie Rhorer <lesrhorer@att.net>
Cc: antlists <antlists@youngman.org.uk>,
	Linux RAID <linux-raid@vger.kernel.org>
Subject: Re: My superblocks have gone missing, can't reassemble raid5
Date: Thu, 20 May 2021 21:49:26 +0100	[thread overview]
Message-ID: <87a6opnnah.fsf@esperi.org.uk> (raw)
In-Reply-To: <60de3096-95e8-ca32-3c83-982bf8409167@att.net> (Leslie Rhorer's message of "Wed, 19 May 2021 18:45:47 -0500")

On 20 May 2021, Leslie Rhorer outgrape:

> On 5/19/2021 3:01 PM, antlists wrote:
>> Yes you can explicitly specify everything, and get mdadm to recover the array if the superblocks have been lost, but it's nowhere
>> as simple as "there are only three possible combinations".
>
> 	The number of permutations of the order of three drives is precisely six.  The permutations are:
>
> 1, 2, 3
>
> 1, 3, 2
>
> 2, 1, 3
>
> 2, 3, 1
>
> 3, 1, 2
>
> 3, 2, 1
>
> 	The Examine stated it was 2, 3, 1, but the device order is not
> at all unlikely to have changed. Once again, I was very explicit in
> saying the simple create may not work and if not he is facing some
> much more serious issues. That was and is in no way incorrect. The
> odds one of them will work are not terrible, and if so, he is in good
> shape. Are you seriously implying there is no way any of them could
> possibly work?

Of course not, but it's *likely* none will work. mdadm's default chunk
size has probably changed since the array was created if it's more than
a few years old, for starters.

  reply	other threads:[~2021-05-20 20:49 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-17  4:16 My superblocks have gone missing, can't reassemble raid5 Christopher Thomas
2021-05-17  4:23 ` Christopher Thomas
2021-05-17  6:28 ` Roman Mamedov
2021-05-17  9:30   ` Wols Lists
     [not found]   ` <CAAMCDec=H=6ceP9bKjSnsQyvmZ0LqTAYzJTDmDQoBOHSJV+hDw@mail.gmail.com>
2021-05-17 13:19     ` Roman Mamedov
2021-05-18 17:47       ` Phil Turmel
2021-05-18 18:31         ` Reindl Harald
2021-05-19 13:20           ` Leslie Rhorer
2021-05-19 13:41             ` Phil Turmel
2021-05-19 16:54               ` Leslie Rhorer
2021-05-20 19:37               ` Nix
2021-06-07  9:52                 ` Leslie Rhorer
2021-05-19 14:20             ` Andy Smith
2021-05-19 14:59               ` Leslie Rhorer
2021-05-19 14:48 ` Leslie Rhorer
2021-05-19 16:41   ` antlists
2021-05-19 17:03     ` Leslie Rhorer
2021-05-19 17:08     ` Leslie Rhorer
2021-05-19 18:00       ` Wols Lists
2021-05-19 19:01         ` Leslie Rhorer
2021-05-19 20:01           ` antlists
2021-05-19 23:45             ` Leslie Rhorer
2021-05-20 20:49               ` Nix [this message]
2021-05-21  4:07                 ` Leslie Rhorer
2021-06-07  9:55                   ` Leslie Rhorer
2021-05-20 20:48           ` Nix
2021-05-21  3:56             ` Leslie Rhorer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87a6opnnah.fsf@esperi.org.uk \
    --to=nix@esperi.org.uk \
    --cc=antlists@youngman.org.uk \
    --cc=lesrhorer@att.net \
    --cc=linux-raid@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.