CentOS - May 2020 - Recover from an fsck failure

This is CentOS-6x.

I have cloned the HDD of a CentOS-6 system.  I booted a host with that drive
and received the following error:

checking filesystems

/dev/mapper/vg_voinet01-lv_root: clean, 128491/4096000 files, 1554114/16304000
blocks

/dev/sda1: clean, 47/120016 files, 80115/512000 blocks

/dev/mapper/vg_voinet01-lv_home: clean, 7429/204800 files, 90039/819200 blocks

/dev/mapper/vg_voinet01-LogVol04: clean, 770219/20480000 files,
34881086/8102000 blocks

fsck.ext4: Bad magic number in super-block while trying to open
/dev/mapper/vg_voinet01-lv_log
/dev/mapper/vg_voinet01-lv_log
The superblock could not be read or does not describe a correct ext2
filesystem. If the device is valid and it really contains an ext2 filesystem
(and not swap or ufs or something else), then the superblock is corrupt, and
you might try running e2fsck with an alternate superblock:
  e2fsk -b 8193 <device>

/dev/mapper/vg_voinet-lv_spool: clean, 372/614400 files, 171186/2457600 blocks

*** An error occurred during the file system check.
*** Dropping you to a shell; the system will reboot
*** when you leave the shell.
Give root password for maintenance
(or type Control-D to continue):


I ran mke2fs to locate the backup superblocks:

mke2fs -n /dev/mapper/vg_voinet01-lv_log
. . .
Superblock backups stored on blocks:
      32768, 90304,  163840, 229376, 294912, 819200, 884736, 1605632

and ran:

e2fsck -b 32768 /dev/mapper/vg_voinet01-lv_log
The superblock could not be read or does not describe a correct ext2

The same thing happened for the next backup superblock addrees.  And all the
rest reported an invalid argument error from e2fsck.

Is this recoverable?  How?

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> 
> I ran mke2fs to locate the backup superblocks:
> 
> mke2fs -n /dev/mapper/vg_voinet01-lv_log
That will only tell you what mke2fs would do on that machine. I don't
know if it will be the same on every machine.  You should probably run 

 dumpe2fs /dev/mapper/vg_voinet01-lv_log | grep superblock

If that doesn't work, then I suspect it's not recoverable using fsck. 
If you are sure that it is an ext2/3/4 filesystem on there, then you
can try using something like TestDisk to scan for partitions.  It
should be in epel.

P.

On 5/28/20 1:33 PM, James B. Byrne via CentOS wrote:
> /dev/mapper/vg_voinet01-lv_log
> The superblock could not be read or does not describe a correct ext2
> filesystem. If the device is valid and it really contains an ext2
filesystem
> (and not swap or ufs or something else), then the superblock is corrupt,
and
> you might try running e2fsck with an alternate superblock:
>    e2fsk -b 8193 <device>
What output do you get from:

     file -s /dev/mapper/vg_voinet01-lv_log
     lsblk -f /dev/mapper/vg_voinet01-lv_log

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