-?????????? ? ? ? ? ? shadow
If you see this you are probably in big trouble, it could be a physical error or if it's a VM image that it is corrupted due to a physical error on the underlying disk/array/NAS or it could also be that somehow the image was accessed and mounted more than once concurrently. This is almost always impossible to fix but you can always try to fsck anyway!
----------. 1 root root 748 Jul 10 04:35 shadow-
cat: shadow: Input/output error
fsck /dev/mapper/loop5p1
fsck 1.45.6 (20-Mar-2020)
e2fsck 1.45.6 (20-Mar-2020)
/dev/mapper/loop5p1 contains a file system with errors, check forced.
Pass 1: Checking inodes, blocks, and sizes
Deleted inode 11383 has zero dtime. Fix<y>? yes
Deleted inode 11387 has zero dtime. Fix<y>? yes
Deleted inode 11388 has zero dtime. Fix<y>? yes
Pass 2: Checking directory structure
Entry 'shadow' in /etc (13) has deleted/unused inode 11390. Clear<y>? yes
Entry 'shadow-202007141594765348' in /etc (13) has deleted/unused inode 11386. Clear<y>? yes
Entry 'shadow-202007141594770924' in /etc (13) has deleted/unused inode 11386. Clear<y>? yes
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Inode 11328 ref count is 1, should be 3. Fix<y>? yes
Pass 5: Checking group summary information
Block bitmap differences: -(45056--47103) -(68608--70172) -(71680--73727) -(77824--77828) -(83968--84460)
Fix<y>? yes
Free blocks count wrong for group #1 (10183, counted=12231).
Fix<y>? yes
Free blocks count wrong for group #2 (11477, counted=15588).
Fix<y>? yes
Free blocks count wrong (675912, counted=682073).
Fix<y>? yes
Inode bitmap differences: -11340 -11383 -(11387--11388)
Fix<y>? yes
Free inodes count wrong for group #1 (4671, counted=4675).
Fix<y>? yes
Free inodes count wrong (242659, counted=242665).
Fix<y>? yes
/dev/mapper/loop5p1: ***** FILE SYSTEM WAS MODIFIED *****
/dev/mapper/loop5p1: 39015/281680 files (0.2% non-contiguous), 442791/1124864 blocks
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