Re: RAID 6, 6 device array - all devices lost superblock

John Stoffel
2022-09-05T19:36:57Z

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

> tried removing the setup:
> root@superior:/mnt/backup# mdadm --stop /dev/md1
> mdadm: stopped /dev/md1
> root@superior:/mnt/backup# parallel 'dmsetup remove {/}; rm
> overlay-{/}' ::: $DEVICES
> ^C

> (ran for an hour before cancel... )

> root@superior:/mnt/backup# dmsetup status
> No devices found
> root@superior:/mnt/backupls
> lost+found overlay-sdb overlay-sdc overlay-sdd overlay-sde
> overlay-sdf overlay-sdg
> root@superior:/mnt/backup# rm overlay-sd*
> root@superior:/mnt/backup# ls /dev/loop
> ls: cannot access '/dev/loop': No such file or directory
> root@superior:/mnt/backup# ls /dev/loop*
> /dev/loop0 /dev/loop2 /dev/loop4 /dev/loop6 /dev/loop-control
> /dev/loop1 /dev/loop3 /dev/loop5 /dev/loop7
> root@superior:/mnt/backup# parallel losetup -d ::: /dev/loop[0-9]*
> losetup: /dev/loop6: detach failed: No such device or address
> losetup: /dev/loop7: detach failed: No such device or address
> root@superior:/mnt/backup# ls /dev/loop*
> /dev/loop0 /dev/loop2 /dev/loop4 /dev/loop6 /dev/loop-control
> /dev/loop1 /dev/loop3 /dev/loop5 /dev/loop7
> root@superior:/mnt/backup# ls -la /dev/lo*
> lrwxrwxrwx 1 root root 28 Sep 2 20:22 /dev/log ->
> /run/systemd/journal/dev-log
> brw-rw---- 1 root disk 7, 0 Sep 2 20:32 /dev/loop0
> brw-rw---- 1 root disk 7, 1 Sep 2 20:32 /dev/loop1
> brw-rw---- 1 root disk 7, 2 Sep 2 20:32 /dev/loop2
> brw-rw---- 1 root disk 7, 3 Sep 2 20:32 /dev/loop3
> brw-rw---- 1 root disk 7, 4 Sep 2 20:32 /dev/loop4
> brw-rw---- 1 root disk 7, 5 Sep 2 20:32 /dev/loop5
> brw-rw---- 1 root disk 7, 6 Sep 2 20:32 /dev/loop6
> brw-rw---- 1 root disk 7, 7 Sep 2 20:32 /dev/loop7
> crw-rw---- 1 root disk 10, 237 Sep 2 20:32 /dev/loop-control
> root@superior:/mnt/backup# losetup -d ::: /dev/loop70
> losetup: :::: failed to use device: No such device
> root@superior:/mnt/backup# losetup -d ::: /dev/loop7
> losetup: :::: failed to use device: No such device
> root@superior:/mnt/backup# losetup -d /dev/loop7
> losetup: /dev/loop7: detach failed: No such device or address
> root@superior:/mnt/backup# ls -la /dev/loop*
> brw-rw---- 1 root disk 7, 0 Sep 2 20:32 /dev/loop0
> brw-rw---- 1 root disk 7, 1 Sep 2 20:32 /dev/loop1
> brw-rw---- 1 root disk 7, 2 Sep 2 20:32 /dev/loop2
> brw-rw---- 1 root disk 7, 3 Sep 2 20:32 /dev/loop3
> brw-rw---- 1 root disk 7, 4 Sep 2 20:32 /dev/loop4
> brw-rw---- 1 root disk 7, 5 Sep 2 20:32 /dev/loop5
> brw-rw---- 1 root disk 7, 6 Sep 2 20:32 /dev/loop6
> brw-rw---- 1 root disk 7, 7 Sep 2 20:32 /dev/loop7
> crw-rw---- 1 root disk 10, 237 Sep 2 20:32 /dev/loop-control
> root@superior:/mnt/backup# losetup /dev/loop7
> losetup: /dev/loop7: No such file or directory
> root@superior:/mnt/backup# losetup /dev/loop5
> losetup: /dev/loop5: No such file or directory
> root@superior:/mnt/backup#

> not sure why losetup cannot see the existing /dev/loopx devices.

I was reading the dmsetup man page and it said that if the devices are
open, when you do a remove, it sorta fails them and then blocks them
as unable to have more IO sent to them. But honestly I'm not an
expert on dmsetup.

But sure, try to reboot each time, but you also need to make sure the
disks are in the same positions each time after reboot, so look at the
serial numbers.

lsscsi -g -l

might be enough to give you unique or instead use:

hdparm -i /dev/sda | grep SerialNo

to get the info and keep track of which disk is in which order.

John

> On Fri, Sep 2, 2022 at 8:39 PM Peter Sanders <plsander@gmail.com> wrote:
>>
>> Repeat of run 1
>>
>> plsander@superior:~$ su -
>> Password:
>> root@superior:~# cat /proc/partitions
>> major minor #blocks name
>>
>> 259 0 250059096 nvme0n1
>> 259 1 496640 nvme0n1p1
>> 259 2 1 nvme0n1p2
>> 259 3 63475712 nvme0n1p5
>> 259 4 97654784 nvme0n1p6
>> 259 5 37888 nvme0n1p7
>> 259 6 86913024 nvme0n1p8
>> 259 7 1474560 nvme0n1p9
>> 8 16 2930266584 sdb
>> 8 80 2930266584 sdf
>> 8 0 1953514584 sda
>> 8 1 1953513472 sda1
>> 8 32 2930266584 sdc
>> 8 96 2930266584 sdg
>> 8 64 2930266584 sde
>> 8 48 2930266584 sdd
>> 11 0 1048575 sr0
>> root@superior:~# cat /proc/mdstat
>> Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5]
>> [raid4] [raid10]
>> unused devices: <none>
>> root@superior:~# DEVICES="/dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg"
>> root@superior:~# echo $DEVICES
>> /dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg
>> root@superior:~# parallel 'test -e /dev/loop{#} || mknod -m 660
>> /dev/loop{#} b 7 {#}' ::: $DEVICES
>> root@superior:~# ls /dev/lo
>> log loop2 loop4 loop6
>> loop1 loop3 loop5 loop-control
>> root@superior:~# ls /dev/lo*
>> /dev/log /dev/loop1 /dev/loop2 /dev/loop3 /dev/loop4 /dev/loop5
>> /dev/loop6 /dev/loop-control
>> root@superior:~# ls -l /dev/loop*
>> brw-rw---- 1 root root 7, 1 Sep 2 20:30 /dev/loop1
>> brw-rw---- 1 root root 7, 2 Sep 2 20:30 /dev/loop2
>> brw-rw---- 1 root root 7, 3 Sep 2 20:30 /dev/loop3
>> brw-rw---- 1 root root 7, 4 Sep 2 20:30 /dev/loop4
>> brw-rw---- 1 root root 7, 5 Sep 2 20:30 /dev/loop5
>> brw-rw---- 1 root root 7, 6 Sep 2 20:30 /dev/loop6
>> crw-rw---- 1 root disk 10, 237 Sep 2 20:22 /dev/loop-control
>> root@superior:~# cd /mnt/backup/
>> root@superior:/mnt/backup# parallel truncate -s4000G overlay-{/} ::: $DEVICES
>> root@superior:/mnt/backup# ls -l
>> total 16
>> drwx------ 2 root root 16384 Aug 28 18:50 lost+found
>> -rw-r--r-- 1 root root 4294967296000 Sep 2 20:31 overlay-sdb
>> -rw-r--r-- 1 root root 4294967296000 Sep 2 20:31 overlay-sdc
>> -rw-r--r-- 1 root root 4294967296000 Sep 2 20:31 overlay-sdd
>> -rw-r--r-- 1 root root 4294967296000 Sep 2 20:31 overlay-sde
>> -rw-r--r-- 1 root root 4294967296000 Sep 2 20:31 overlay-sdf
>> -rw-r--r-- 1 root root 4294967296000 Sep 2 20:31 overlay-sdg
>> root@superior:/mnt/backup# rm over*
>> root@superior:/mnt/backup# parallel truncate -s300G overlay-{/} ::: $DEVICES
>> root@superior:/mnt/backup# ls -la
>> total 24
>> drwxr-xr-x 3 root root 4096 Sep 2 20:31 .
>> drwxr-xr-x 7 root root 4096 Aug 29 09:17 ..
>> drwx------ 2 root root 16384 Aug 28 18:50 lost+found
>> -rw-r--r-- 1 root root 322122547200 Sep 2 20:31 overlay-sdb
>> -rw-r--r-- 1 root root 322122547200 Sep 2 20:31 overlay-sdc
>> -rw-r--r-- 1 root root 322122547200 Sep 2 20:31 overlay-sdd
>> -rw-r--r-- 1 root root 322122547200 Sep 2 20:31 overlay-sde
>> -rw-r--r-- 1 root root 322122547200 Sep 2 20:31 overlay-sdf
>> -rw-r--r-- 1 root root 322122547200 Sep 2 20:31 overlay-sdg
>> root@superior:/mnt/backup# dmsetup status
>> No devices found
>> root@superior:/mnt/backup# date
>> Fri 02 Sep 2022 08:32:11 PM EDT
>> root@superior:/mnt/backup# parallel 'size=$(blockdev --getsize {});
>> loop=$(losetup -f --show -- overlay-{/}); echo 0 $size snapshot {}
>> $loop P 8 | dmsetup create {/}' ::: $DEVICES
>> root@superior:/mnt/backup# date
>> Fri 02 Sep 2022 08:32:20 PM EDT
>> root@superior:/mnt/backup# dmsetup status
>> sdg: 0 5860533168 snapshot 16/629145600 16
>> sdf: 0 5860533168 snapshot 16/629145600 16
>> sde: 0 5860533168 snapshot 16/629145600 16
>> sdd: 0 5860533168 snapshot 16/629145600 16
>> sdc: 0 5860533168 snapshot 16/629145600 16
>> sdb: 0 5860533168 snapshot 16/629145600 16
>> root@superior:/mnt/backup# OVERLAYS=$(parallel echo /dev/mapper/{/}
>> ::: $DEVICES)
>> root@superior:/mnt/backup# echo $OVERLAYS
>> /dev/mapper/sdb /dev/mapper/sdc /dev/mapper/sdd /dev/mapper/sde
>> /dev/mapper/sdf /dev/mapper/sdg
>> root@superior:/mnt/backup# mdadm --create /dev/md1 --level=raid6 -n 6
>> --assume-clean $OVERLAYS
>> mdadm: partition table exists on /dev/mapper/sdb
>> mdadm: partition table exists on /dev/mapper/sdc
>> mdadm: partition table exists on /dev/mapper/sdc but will be lost or
>> meaningless after creating array
>> mdadm: partition table exists on /dev/mapper/sdd
>> mdadm: partition table exists on /dev/mapper/sdd but will be lost or
>> meaningless after creating array
>> mdadm: partition table exists on /dev/mapper/sde
>> mdadm: partition table exists on /dev/mapper/sde but will be lost or
>> meaningless after creating array
>> mdadm: partition table exists on /dev/mapper/sdf
>> mdadm: partition table exists on /dev/mapper/sdf but will be lost or
>> meaningless after creating array
>> mdadm: partition table exists on /dev/mapper/sdg
>> mdadm: partition table exists on /dev/mapper/sdg but will be lost or
>> meaningless after creating array
>> Continue creating array? y
>> mdadm: Defaulting to version 1.2 metadata
>> mdadm: array /dev/md1 started.
>> root@superior:/mnt/backup# ls -l /dev/md*
>> brw-rw---- 1 root disk 9, 1 Sep 2 20:34 /dev/md1
>> root@superior:/mnt/backup# fsck /dev/md1
>> fsck from util-linux 2.36.1
>> e2fsck 1.46.2 (28-Feb-2021)
>> ext2fs_open2: Bad magic number in super-block
>> fsck.ext2: Superblock invalid, trying backup blocks...
>> fsck.ext2: Bad magic number in super-block while trying to open /dev/md1
>>
>> The superblock could not be read or does not describe a valid ext2/ext3/ext4
>> filesystem. If the device is valid and it really contains an ext2/ext3/ext4
>> filesystem (and not swap or ufs or something else), then the superblock
>> is corrupt, and you might try running e2fsck with an alternate superblock:
>> e2fsck -b 8193 <device>
>> or
>> e2fsck -b 32768 <device>
>>
>> root@superior:/mnt/backup# blkid /dev/md1
>> root@superior:/mnt/backup#
>> root@superior:/mnt/backup# cat /proc/mdstat
>> Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5]
>> [raid4] [raid10]
>> md1 : active raid6 dm-3[5] dm-2[4] dm-1[3] dm-5[2] dm-0[1] dm-4[0]
>> 11720536064 blocks super 1.2 level 6, 512k chunk, algorithm 2
>> [6/6] [UUUUUU]
>> bitmap: 0/22 pages [0KB], 65536KB chunk
>>
>> unused devices: <none>
>> root@superior:/mnt/backup#
>>
>> Some questions -
>> - is the easiest 'reset for next run' to reboot and rebuild?
>>
>>
>> On Fri, Sep 2, 2022 at 3:12 PM John Stoffel <john@stoffel.org> wrote:
>> >
>> > >>>>> "Peter" == Peter Sanders <plsander@gmail.com> writes:
>> >
>> > Peter, please include the output of all the commands, not just the
>> > commands themselves. See my comments below.
>> >
>> >
>> > > Question on restarting from scratch...
>> > > How to reset to the starting point?
>> >
>> > I think you need to blow away the loop devices and re-create them.
>> >
>> > Or at least blow away the dmsetup devices you just created.
>> >
>> > It might be quickest to just reboot. What OS are you using for the
>> > recovery? Is it a recent live image? Sorry for asking so many
>> > questions... some of this is new to me too.
>> >
>> >
>> > > dmsetup, both for remove and create of the overlay seems to be hanging.
>> >
>> > > On Fri, Sep 2, 2022 at 10:56 AM Peter Sanders <plsander@gmail.com> wrote:
>> > >>
>> > >> contents of /proc/mdstat
>> > >>
>> > >> root@superior:/mnt/backup# cat /proc/mdstat
>> > >> Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5]
>> > >> [raid4] [raid10]
>> > >> unused devices: <none>
>> > >> root@superior:/mnt/backup#
>> > >>
>> > >>
>> > >>
>> > >> Here are the steps I ran (minus some mounting other devices and
>> > >> looking around for mdadm tracks on the old os disk)
>> > >>
>> > >> 410 DEVICES=$(cat /proc/partitions | parallel --tagstring {5}
>> > >> --colsep ' +' mdadm -E /dev/{5} |grep $UUID | parallel --colsep '\t'
>> > >> echo /dev/{1})
>> > >> 411 apt install parallel
>> > >> 412 DEVICES=$(cat /proc/partitions | parallel --tagstring {5}
>> > >> --colsep ' +' mdadm -E /dev/{5} |grep $UUID | parallel --colsep '\t'
>> > >> echo /dev/{1})
>> > >> 413 echo $DEVICES
>> >
>> > So you found no MD RAID super blocks on any of the base devices. You
>> > can skip this step moving forward.
>> >
>> > >> 414 cat /proc/partitions
>> > >> 415 DEVICES=/dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg
>> > >> 416 DEVICES="/dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg"
>> > >> 417 echo $DEVICES
>> > >> 418 parallel 'test -e /dev/loop{#} || mknod -m 660 /dev/loop{#} b 7
>> > >> {#}' ::: $DEVICES
>> > >> 419 ls /dev/loop*
>> >
>> > Can you show the output of all these commands, not just the commands please?
>> >
>> > >> 423 parallel truncate -s300G overlay-{/} ::: $DEVICES
>> >
>> > >> 427 parallel 'size=$(blockdev --getsize {}); loop=$(losetup -f
>> > >> --show -- overlay-{/}); echo 0 $size snapshot {} $loop P 8 | dmsetup
>> > >> create {/}' ::: $DEVICES
>> > >> 428 ls /dev/mapper/
>> >
>> > This is some key output to view.
>> >
>> > >> 429 OVERLAYS=$(parallel echo /dev/mapper/{/} ::: $DEVICES)
>> > >> 430 echo $OVERLAYS
>> >
>> > What are the overlays?
>> >
>> > >> 431 dmsetup status
>> >
>> > What did this command show?
>> >
>> > >> 432 mdadm --assemble --force /dev/md1 $OVERLAYS
>> >
>> > And here is where I think you need to put --assume-clean when using
>> > 'create' command instead. It's not going to assemble anything because
>> > the info was wiped. I *think* you really want:
>> >
>> > mdadm --create /dev/md1 --level=raid6 -n 6 --assume-clean $OVERLAYS
>> >
>> > And once you do this above command and it comes back, do:
>> >
>> > cat /proc/mdstat
>> >
>> > and show all the output please!
>> >
>> > >> 433 history
>> > >> 434 dmsetup status
>> > >> 435 echo $OVERLAYS
>> > >> 436 mdadm --assemble --force /dev/md0 $OVERLAYS
>> > >> 437 cat /proc/partitions
>> > >> 438 mkdir /mnt/oldroot
>> > >> << look for inird mdadm files >>
>> > >> 484 echo $OVERLAYS
>> > >> 485 mdadm --create /dev/md0 --level=raid6 -n 6 /dev/mapper/sdb
>> > >> /dev/mapper/sdc /dev/mapper/sdd /dev/mapper/sde /dev/mapper/sdf
>> > >> /dev/mapper/sdg
>> >
>> > I'm confused here, what is the difference between the md1 you
>> > assembled above, and the md0 you're doing here?
>> >
>> > >> << cancelled out of 485, review instructions... >>
>> > >> 486 mdadm --create /dev/md0 --level=raid6 -n 6 /dev/mapper/sdb
>> > >> /dev/mapper/sdc /dev/mapper/sdd /dev/mapper/sde /dev/mapper/sdf
>> > >> /dev/mapper/sdg
>> > >> 487 fsck -n /dev/md0
>> >
>> > And what output did you get here? Did it find a filesystem? You might want
>> > to try:
>> >
>> > blkid /dev/md0
>> >
>> >
>> > >> 488 mdadm --stop /dev/md0
>> > >> 489 echo $DEVICES
>> > >> 490 parallel 'dmsetup remove {/}; rm overlay-{/}' ::: $DEVICES
>> > >> 491 dmsetup status
>> >
>> > This all worked properly? No errors?
>> >
>> > I gave up after this because it's not clear what the results really
>> > are. If you don't find a filesystem that fsck's cleanly, then you
>> > should just need to stop the array, then re-create it but shuffle the
>> > order of the devices.
>> >
>> > Instead of disk in order of "sdb sdc sdd... sdN", you would try the
>> > order "sdc sdd ... sdN sdb". See how I moved sdb to the end of the
>> > list of devices? With six disks, you have I think 6 factorial options
>> > to try. Which is alot of options to go though, and why you need to
>> > automate this more. But also keep a log and show the output!
>> >
>> > John
>> >
>> >
>> > >> 492 ls
>> > >> 493 rm overlay-*
>> > >> 494 ls
>> > >> 495 parallel losetup -d ::: /dev/loop[0-9]*
>> > >> 496 parallel 'test -e /dev/loop{#} || mknod -m 660 /dev/loop{#} b 7
>> > >> {#}' ::: $DEVICES
>> > >> 497 parallel truncate -s300G overlay-{/} ::: $DEVICES
>> > >> 498 parallel 'size=$(blockdev --getsize {}); loop=$(losetup -f
>> > >> --show -- overlay-{/}); echo 0 $size snapshot {} $loop P 8 | dmsetup
>> > >> create {/}' ::: $DEVICES
>> > >> 499 dmsetup status
>> > >> 500 /sbin/reboot
>> > >> 501 history
>> > >> 502 dmsetup status
>> > >> 503 mount
>> > >> 504 cat /proc/partitions
>> > >> 505 nano /etc/fstab
>> > >> 506 mount /mnt/backup/
>> > >> 507 ls /mnt/backup/
>> > >> 508 rm /mnt/backup/
>> > >> 509 rm /mnt/backup/overlay-sd*
>> > >> 510 emacs setupOverlay &
>> > >> 511 ps auxww | grep emacs
>> > >> 512 kill 65017
>> > >> 513 ls /dev/loo*
>> > >> 514 DEVICES='/dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg'
>> > >> 515 echo $DEVICES
>> > >> 516 parallel 'test -e /dev/loop{#} || mknod -m 660 /dev/loop{#} b
>> > >> 7 {#}' ::: $DEVICES
>> > >> 517 ls /dev/loo*
>> > >> 518 parallel truncate -s4000G overlay-{/} ::: $DEVICES
>> > >> 519 ls
>> > >> 520 rm overlay-sd*
>> > >> 521 cd /mnt/bak
>> > >> 522 cd /mnt/backup/
>> > >> 523 ls
>> > >> 524 parallel truncate -s4000G overlay-{/} ::: $DEVICES
>> > >> 525 ls -la
>> > >> 526 blockdev --getsize /dev/sdb
>> > >> 527 man losetup
>> > >> 528 man losetup
>> > >> 529 parallel 'size=$(blockdev --getsize {}); loop=$(losetup -f
>> > >> --show -- overlay-{/}); echo 0 $size snapshot {} $loop P 8 | dmsetup
>> > >> create {/}' ::: $DEVICES
>> > >> 530 dmsetup status
>> > >> 531 history | grep mdadm
>> > >> 532 history
>> > >> 533 dmsetup status
>> > >> 534 history | grep dmsetup
>> > >> 535 dmsetup status
>> > >> 536 dmsetup remove sdg
>> > >> 537 dmsetup ls --tree
>> > >> 538 lsof
>> > >> 539 dmsetup ls --tre
>> > >> 540 dmsetup ls --tree
>> > >> 541 lsof | grep -i sdg
>> > >> 542 lsof | grep -i sdf
>> > >> 543 history |grep dmsetup | less
>> > >> 544 dmsetup status
>> > >> 545 history > ~plsander/Documents/raidIssues/joblog
>> > >>
>> > >> On Wed, Aug 31, 2022 at 4:37 PM John Stoffel <john@stoffel.org> wrote:
>> > >> >
>> > >> > >>>>> "Peter" == Peter Sanders <plsander@gmail.com> writes:
>> > >> >
>> > >> > > encountering a puzzling situation.
>> > >> > > dmsetup is failing to return.
>> > >> >
>> > >> > I don't think you need to use dmsetup in your case, but can you post
>> > >> > *all* the commands you ran before you got to this point, and the
>> > >> > output of
>> > >> >
>> > >> > cat /proc/mdstat
>> > >> >
>> > >> > as well? Thinking on this some more, you might need to actually also
>> > >> > add:
>> > >> >
>> > >> > --assume-clean
>> > >> >
>> > >> > to the 'mdadm create ....' string, since you don't want it to zero the
>> > >> > array or anything.
>> > >> >
>> > >> > Sorry for not remembering this at the time!
>> > >> >
>> > >> > So if you can, please just start over from scratch, showing the setup
>> > >> > of the loop devices, the overlayfs setup, and the building the RAID6
>> > >> > array, along with the cat /proc/mdstat after you do the initial build.
>> > >> >
>> > >> > John
>> > >> >
>> > >> > P.S. For those who hated my email citing tool, I pulled it out for
>> > >> > now. Only citing with > now. :-)
>> > >> >
>> > >> > > root@superior:/mnt/backup# dmsetup status
>> > >> > > sdg: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sdf: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sde: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sdd: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sdc: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sdb: 0 5860533168 snapshot 16/8388608000 16
>> > >> >
>> > >> > > dmsetup remove sdg runs for hours.
>> > >> > > Canceled it, ran dmsetup ls --tree and find that sdg is not present in the list.
>> > >> >
>> > >> > > dmsetup status shows:
>> > >> > > sdf: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sde: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sdd: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sdc: 0 5860533168 snapshot 16/8388608000 16
>> > >> > > sdb: 0 5860533168 snapshot 16/8388608000 16
>> > >> >
>> > >> > > dmsetup ls --tree
>> > >> > > root@superior:/mnt/backup# dmsetup ls --tree
>> > >> > > sdf (253:3)
>> > >> > > ├─ (7:3)
>> > >> > > └─ (8:80)
>> > >> > > sde (253:1)
>> > >> > > ├─ (7:1)
>> > >> > > └─ (8:64)
>> > >> > > sdd (253:2)
>> > >> > > ├─ (7:2)
>> > >> > > └─ (8:48)
>> > >> > > sdc (253:0)
>> > >> > > ├─ (7:0)
>> > >> > > └─ (8:32)
>> > >> > > sdb (253:5)
>> > >> > > ├─ (7:5)
>> > >> > > └─ (8:16)
>> > >> >
>> > >> > > any suggestions?
>> > >> >
>> > >> >
>> > >> >
>> > >> > > On Tue, Aug 30, 2022 at 2:03 PM Wols Lists <antlists@youngman.org.uk> wrote:
>> > >> > >>
>> > >> > >> On 30/08/2022 14:27, Peter Sanders wrote:
>> > >> > >> >
>> > >> > >> > And the victory conditions would be a mountable file system that passes a fsck?
>> > >> > >>
>> > >> > >> Yes. Just make sure you delve through the file system a bit and satisfy
>> > >> > >> yourself it looks good, too ...
>> > >> > >>
>> > >> > >> Cheers,
>> > >> > >> Wol