Missing initramfs

Support
1

Asking for a friend. He’s just done an update to his system and is getting a Grub message saying that he needs to load the kernel first. We have tried chrooting into his system to re-install the kernel but this fails having tried to mount /dev/sda1. The error message is
/bin/bash Input/output error

Mate has tried starting the machine from one of the fallback images in Grub but nothing happens. I think this is due to there being no initramfs images in /boot. How do we regenerate a initramfs image in this situation?

2

Chroot into the system and run update-grub.

3

He can’t chroot into the system. Thats one of the problems.

4

Could be corrupted filesystem. What filesystem are you using? If ext4, fsck is your friend

5

can you check
boot from USB iso manjaro

Step 1

sudo manjaro-chroot -a ( if only 0 appears type 1 )
mkinitcpio -P
exit

  • check if all /etc/mkinitcpio.d/*.preset are presents with mhwd-kernel -li
    you have to get one preset for one linux version

  • check also if latest is present , then remove all ( kernel , header , drivers with kernel )

and redo step 1

6

@ stephane
He cannot chroot in at all.

@ Chrysostomus
/dev/sda1 is ext4

7

can you run a fsck on partition ?

if no more chroot possible , do backup data ( home ) , and re-install

8

He has tried fsck but is told that the partition is in use.Rebooted, unmounted /dev/sda and /dev/sda1. Now getting “bad magic number in superblock”.

I’m guessing this is heading for a re-install :pensive:

9

Howdy!
What is the output of lsblk in the live session , may I ask?

Which are the boot and system partitions?

Is it a EFI installation?

10

@ The_Quantum_Alpha
My mate has gone offline for the night. We can have a look @ lsblk in the morning. IIRC boot and system are both on /dev/sda1.

I think it is an EFI install. I think that Grub shows the boot partition as (hd0, gpt2) I have to admit that I tend to stick with MBR on a legacy Bios system.

11

Why was it mounted? Can you reboot the live system without mounting /dev/sda?

12

lsblk shows a single ext4 partition.

grub.cfg is hd0, gpt1. Not sure how i tell whether is is an EFI install though. I don’t think /boot/efi exists so I am guessing that this is not an EFI installation

13

You can copy the backup superblock to superblock, which is bad.

14

I think we have taken the path of least resistance and re-installed the OS. Thanks for all your help.

15

Just in case someone see this later. You can solve this by replacing the first superblock with a backup superblock on the disk:

dumpe2fs -h /dev/sdY

will show you the block number of all superblocks like this:

dumpe2fs 1.42.9 (28-Dec-2013)
Primary superblock at 0, Group descriptors at 1-2
Backup superblock at 32768, Group descriptors at 32769-32770
Backup superblock at 98304, Group descriptors at 98305-98306
Backup superblock at 163840, Group descriptors at 163841-163842
Backup superblock at 229376, Group descriptors at 229377-229378
Backup superblock at 294912, Group descriptors at 294913-294914
Backup superblock at 819200, Group descriptors at 819201-819202
Backup superblock at 884736, Group descriptors at 884737-884738
Backup superblock at 1605632, Group descriptors at 1605633-1605634
Backup superblock at 2654208, Group descriptors at 2654209-2654210

Then you need to repair the file system:

fsck -b 32768 /dev/sdY

You can try every superblock until it repairs correctly.

Also… i would guess that the HDD has badblocks. The file system needs to know that there are badblocks and that it should skip them. More information here: badblocks - ArchWiki

1 Like
16

@megavolt

Nice writeup! Definitely something to note for later!

17

I know the issue is fixed in meantime (by re-install) but reading that made me :roll_eyes:
Because /dev/sda means the whole disk and /dev/sda1 means first partition on that disk…
So how you guys managed to mount both is :confused: me, as you can’t have a partition table if you have a filesystem formatted on the raw disk space…
(Which is the reason for that error message about superblock)

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