Chris,
/ext2_saved and /ext4 are in / but only temporarily.
I have "inlined" my responses prefixed with '#' below (is this ok to
do?)
George...
On Sunday, February 21, 2021, 1:48:52 PM PST, Chris Murphy
<lists(a)colorremedies.com> wrote:
On Sun, Feb 21, 2021 at 2:34 PM Chris Murphy <lists(a)colorremedies.com> wrote:
On Sun, Feb 21, 2021 at 2:16 PM George R Goffe via test
<test(a)lists.fedoraproject.org> wrote:
>
> fc35-bash 5.1 ~# mount -t ext4 -o loop,ro /ext2_saved/image /ext4
> mount: /ext4: can't read superblock on /dev/loop0.
Hmm. That's unexpected though. I'm going to try it in a VM. It should work.
Works for me. But I'm confused by your paths, i.e. are you really
creating /ext2_saved and /ext4 in the root directory?
Assume root user:
mount /dev/vdb /mnt/btrfs
# on this system here vdb is sda8. /mnt/btrfs is /export/home
mount -t ext4 -o ro,loop /mnt/btrfs/ext2_saved/image /mnt/ext4
# result is unchanged:
mount -t ext4 -o ro,loop /export/home/ext2_saved/image /mnt/ext4
mount: /mnt/ext4: can't read superblock on /dev/loop0.
That works for me. But you could alternatively try:
mount /dev/vdb /mnt/btrfs
losetup -r /dev/loop0 /mnt/btrfs/ext2_saved/image
# losetup
NAME SIZELIMIT OFFSET AUTOCLEAR RO BACK-FILE DIO LOG-SEC
/dev/loop0 0 0 0 1 /export/home/ext2_saved/image 0 512
blkid /dev/loop0
# this command responds with nothing
# blkid --version responds with:
blkid from util-linux 2.36.2 (libblkid 2.36.2, 12-Feb-2020)
What file system does libblkid think it is? Could be ext2, ext3, or
ext4, in which case mount -t ext4 exclusively mounts ext4 and will
otherwise fail.
# the file command responds with:
# file /export/home/ext2_saved/image
#/export/home/ext2_saved/image: ERROR: cannot read `/export/home/ext2_saved/image'
(Input/output error)
--
Chris Murphy