error: no such device ..., unknown filesystem. Entering rescue mode. grub rescue >

[AnnisMonadjem]

Hi,
Problem: see above subject title.

Desktop PC specs:
Linux Mint 20.2 64bit just upgraded from LM20 (when problem started).
Kernel: 5.4.0.74 also tried (5.4.0.26)
Boot-Repair report URL: http://paste.ubuntu.com/p/9Ws7fNDtzK/

What i did:
1) The above problem was appearing sporadically. After many reboots i noticed that i could manually reboot from BIOS /dev/sda2 (ATA ST500DM009-2F110).
I tried activating the lowest/oldest kernel 5.4.0.26 as i have a few years old pc (did not solve the problem).
2) Tried to follow these articles:
https://www.pcsuggest.com/grub-rescue-linux/
https://mintguide.org/system/186-repair ... guyos.html
https://www.easytechguides.com/error-un ... ub-rescue/

grub rescue> ls (hd0) (hd0,msdos1) (hd0,msdos2)
Next I ls individually but none had the /boot/grub
and I didn't know how to proceed further.

3) i followed this article:
https://help.ubuntu.com/community/Boot-Repair

Created a boot-repair unetbootin flash drive
Rebooted PC on boot-repair flash drive
unetbootin reported Boot successfully repaired.
URL: http://paste.ubuntu.com/p/9Ws7fNDtzK/

Restarted pc, but now in BIOS i do not find my ATA drive sda (ST500DM009-2F110).
Rebooted pc several times - did not help - i am still not able to find boot drive sda.

Please, help me with the problem above.

[Moonstone Man]

... in BIOS i do not find my ATA drive sda (ST500DM009-2F110).

Your hardware has failed. Either the machine or the drive has gone toes up and joined the choir invisible. You have some but not much choices:

1) Boot from a usb flash device and try to copy off any important files, but if the BIOS doesn't see the device then this is unlikely to work.

2) Remove the drive and put it into another machine, being careful not to write anything to the drive, and try to recover files that way, then replace the drive. This has the same caveat as 1) above.

3) Replace the drive and restore from backup, but this won't work if the machine itself is faulty.

4) Take it to a repair shop.

5) Replace the whole machine.

[AnnisMonadjem]

Hi Kadaicha Man,

Thank you for your kind reply. I'm very grateful for your support especially because all vendors in this country are either completely ignorant about Linux or absolutely against it and in the past a vendor seemed to have tried to damage my PC rather than to fix it. Otherwise, I'm not able to rely on local vendors, and except buying PC spare parts, I cannot rely on their judgment whatsoever.

I enjoy working with Linux and it is my only operating system for years. The problem is that I need more assistance from Linux Mint Forum to remain in Linux world, for reasons mentioned above.

Background:
May I kindly ask you to re-evaluate once more the state of my PC. For this i will recall some important incidents that took place in the past week prior to the error I reported above in my earlier post.

Few week before, my PC on reboot gave an error with something of "aux" in the specs (i don't recall the entire error message), but the PC would reboot properly. To my best that would indicate the proper with voice, but my VLC was working all fine.

Several times within a pace of a week I would fire up the "Disk" Linux utility and would verify the state of my PC - the reading said OK.

Before I wrote to Linux Mint Forum for help I noticed that beside grub rescue > error the booting drive /dev/sda would should up in the BIOS. I made use of it, manually got hold of it via a Clonezilla CD, made a disk clone to an external drive, and verified backup to be in all respects successful.

May I kindly ask you to be little more specific regarding your comments in your last post. I am definitely a noobie in the Linux world, so please, carry me by my little hand.

Questions

1. Kindly explain to me what I should understand by "machine" in your last post: "Either the machine or the drive has gone toes up". Are you referring to the CPU, the internal cables or else what could be the culprit? How could i find out about it myself (without a local vendor intervention, which are no good to Linux lovers).
2. In your last post you seemed very confident that either the machine or the drive are out. Considering that the Smart drive readings on the Drive utility is OK, would you still evaluate my drive/machine to be depleted, or could there be any other problem.

I'll be waiting for your kind assistance.

[RollyShed]

One cheap way of checking things would be to burn a Mint 20.2 .iso to a USB stick.

Boot the computer from that and check your files on the hard disk and possibly do some work and save to the HD or safer, save to another USB stick, plugged in after booting the computer. If working this way for a day or so, any dropouts by the computer should show up but not destroy anything. If on the other hand you have problems reading things at times from the HD, then it points to that being the problem.

[Moonstone Man]

Considering that the Smart drive readings on the Drive utility is OK, would you still evaluate my drive/machine to be depleted, or could there be any other problem.[/list]

viewtopic.php?f=46&t=353775

Read that, in particular the third, 4th and 5th posts.

Machine = computer.

[AnnisMonadjem]

One cheap way of checking things would be to burn a Mint 20.2 .iso to a USB stick.

Boot the computer from that and check your files on the hard disk and possibly do some work and save to the HD or safer, save to another USB stick, plugged in after booting the computer. If working this way for a day or so, any dropouts by the computer should show up but not destroy anything. If on the other hand you have problems reading things at times from the HD, then it points to that being the problem.

I reboot PC but in BIOS do not find the bootable /sda device (with LM20 system). I only find /sdb (my Data) - my data are secured externally.
Is there any way to gain access to bootable /sda device. I am not sure why it doesn't show up on reboot in BIOS. Is there anything I'm doing wrong?

[AnnisMonadjem]

Considering that the Smart drive readings on the Drive utility is OK, would you still evaluate my drive/machine to be depleted, or could there be any other problem.[/list]

viewtopic.php?f=46&t=353775

Read that, in particular the third, 4th and 5th posts.

Machine = computer.

Thanks for your prompt and informative reply. I've a trip planned to town in the pipe-line this week.

[RollyShed]

I reboot PC but in BIOS do not find the bootable /sda device (with LM20 system). I only find /sdb (my Data) - my data are secured externally.
Is there any way to gain access to bootable /sda device. I am not sure why it doesn't show up on reboot in BIOS. Is there anything I'm doing wrong?

This is definitely why I'd boot it using a USB stick. Note that in the BIOS you have to tell it to boot / look at the USB first. Having booted using the USB stick, you are running a system and should, opening Computer on the screen, see what can be seen. If the data disk is an external one and not connected, then the only other disk visible should be your bootable / sda. If not visible then it tends to indicate that that is the fault i.e. bad disk.

[budgiebandolier]

I have used https://mfcallahan.blog/2021/03/19/erro ... scue-mode/ it might help?!

[AnnisMonadjem]

Considering that the Smart drive readings on the Drive utility is OK, would you still evaluate my drive/machine to be depleted, or could there be any other problem.[/list]

viewtopic.php?f=46&t=353775

Read that, in particular the third, 4th and 5th posts.

Machine = computer.

Hi Kadaitcha Man,
Thank you for your valuable comments and the link to another post, where you said:

One other thing you can do is boot from a live media and run e2fsck:
sudo e2fsck -vfp -C 0 /dev/sdX, where d is the device and X is the partition number.

I would like to possibly give a last try to recover the drive. I'm interested in carrying out the command you offered above.
When I reboot pc (multiple times and at different time) and in bios i do not find drive/device with the operating system LM20 (/dev/sda). The bios does show up and it shows the data drive (/dev/sdb), as well as the installation drive (/dev/sdc).

Is it possible that I have messed up something, or perhaps not doing something right? Could it be possible that /dev/sda is just hiding somewhere?

[AnnisMonadjem]

I reboot PC but in BIOS do not find the bootable /sda device (with LM20 system). I only find /sdb (my Data) - my data are secured externally.
Is there any way to gain access to bootable /sda device. I am not sure why it doesn't show up on reboot in BIOS. Is there anything I'm doing wrong?

This is definitely why I'd boot it using a USB stick. Note that in the BIOS you have to tell it to boot / look at the USB first. Having booted using the USB stick, you are running a system and should, opening Computer on the screen, see what can be seen. If the data disk is an external one and not connected, then the only other disk visible should be your bootable / sda. If not visible then it tends to indicate that that is the fault i.e. bad disk.

Thank you for answering to my last question and clarifying the final problem.

[SimonPeter]

Try running sudo fdisk -l and lsblk in a Terminal from the live USB.
This may show your drive if it is undamaged.

but if the BIOS doesn't see the device then this is unlikely to work.

[mikeflan]

Is it possible that I have messed up something, or perhaps not doing something right?

Just about anything is possible, but we think you are doing every right and the drive is not accessible for some reason.

Could it be possible that /dev/sda is just hiding somewhere?

It could be that the cable or cable connection is bad. I would unplug and plug the drive back in on both ends of the cable. And also plug it into a different SATA slot.

I made use of it, manually got hold of it via a Clonezilla CD, made a disk clone to an external drive, and verified backup to be in all respects successful.

You did good there. Do you have another disk to burn that image to? If not, I would plan to obtain another SSD of the exact same size as the sda disk (or larger).