All of lore.kernel.org
 help / color / mirror / Atom feed
From: "John Stoffel" <john@stoffel.org>
To: Peter Sanders <plsander@gmail.com>
Cc: John Stoffel <john@stoffel.org>, Phil Turmel <philip@turmel.org>,
	Wols Lists <antlists@youngman.org.uk>, NeilBrown <neilb@suse.com>,
	linux-raid@vger.kernel.org
Subject: Re: RAID 6, 6 device array - all devices lost superblock
Date: Mon, 29 Aug 2022 17:45:43 -0400	[thread overview]
Message-ID: <25357.13191.843087.630097@quad.stoffel.home> (raw)
In-Reply-To: <CAKAPSkLQ4K1R_aD1=iURTFQmm_DXDMr=wx+VDET7DOUy+6Zp_Q@mail.gmail.com>

>>>>> "Peter" == Peter Sanders <plsander@gmail.com> writes:

Peter> Phil,
Peter> fstab from the working config -

Peter> # <file system> <mount point>   <type>  <options>       <dump>  <pass>
Peter> # / was on /dev/sda1 during installation
Peter> UUID=50976432-b750-4809-80ac-3bbdd2773163 /               ext4
Peter> errors=remount-ro 0       1
Peter> # /home was on /dev/sda6 during installation
Peter> UUID=eb93a2c4-0190-41fa-a41d-7a5966c6bc47 /home           ext4
Peter> defaults        0       2
Peter> # /var was on /dev/sda5 during installation
Peter> UUID=d1aa6d1f-3ee9-48a8-9350-b15149f738c4 /var            ext4
Peter> defaults        0       2
Peter> /dev/sr0        /media/cdrom0   udf,iso9660 user,noauto     0       0
Peter> /dev/sr1        /media/cdrom1   udf,iso9660 user,noauto     0       0
Peter> # raid array
Peter> /dev/md0    /mnt/raid6    ext4    defaults    0    2

Peter> No LVM, one large EXT4 partition

Peter> I have several large files ( NEF and various mpg files) I can identify
Peter> and have backup copies available.

Peter> I have the overlays created. 300G for each of the six drives.

So that's good.  Now you have to try and figure out which order they
were created in.  As the docs show, you setup the overlayfs on top of
each of the six drives.  

Keep track by noting the drive serial numbers, since Linux can move
them around and change drive letters on reboots.


Then using the overlays, do an:

     mdadm --create /dev/md0 --level=raid6 -n 6 /dev/sd[bcdefg] 
     fsck -n /dev/md0

and see what you get.  If it doesn't look like a real filesystem, then
you can break it down, and then modify the order you give the drive
letters, like:

	 /dev/sd[cdefge]

and rinse and repeat as it goes.  Not fun... but should hopefully fix
things for you.

John

  parent reply	other threads:[~2022-08-29 21:45 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-08-28  2:00 RAID 6, 6 device array - all devices lost superblock Peter Sanders
2022-08-28  9:14 ` Wols Lists
2022-08-28  9:54   ` Wols Lists
2022-08-28 16:47     ` Phil Turmel
     [not found]       ` <CAKAPSkJAQYsec-4zzcePbkJ7Ee0=sd_QvHj4Stnyineq+T8BXw@mail.gmail.com>
2022-08-28 17:16         ` Wols Lists
2022-08-28 18:45         ` John Stoffel
2022-08-28 19:36           ` Phil Turmel
2022-08-28 19:49             ` John Stoffel
2022-08-28 23:24               ` Peter Sanders
2022-08-29 13:12                 ` Peter Sanders
2022-08-29 21:45                 ` John Stoffel [this message]
2022-08-29 22:29                   ` Eyal Lebedinsky
2022-08-29 23:53                     ` Peter Sanders
2022-08-30 13:27                       ` Peter Sanders
2022-08-30 18:03                         ` Wols Lists
2022-08-31 17:48                           ` Peter Sanders
2022-08-31 20:37                             ` John Stoffel
2022-09-02 14:56                               ` Peter Sanders
2022-09-02 18:52                                 ` Peter Sanders
2022-09-02 19:12                                   ` John Stoffel
2022-09-03  0:39                                     ` Peter Sanders
2022-09-03  5:51                                       ` Peter Sanders
2022-09-05 19:36                                         ` John Stoffel
2022-09-05 20:16                                           ` Peter Sanders
2022-09-05 19:25                                       ` John Stoffel
2022-08-28 15:10 ` John Stoffel
2022-08-28 17:11 ` Andy Smith
2022-08-28 17:22   ` Andy Smith
2022-08-28 17:34     ` Peter Sanders

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=25357.13191.843087.630097@quad.stoffel.home \
    --to=john@stoffel.org \
    --cc=antlists@youngman.org.uk \
    --cc=linux-raid@vger.kernel.org \
    --cc=neilb@suse.com \
    --cc=philip@turmel.org \
    --cc=plsander@gmail.com \
    /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.