Ubuntu 'lost' hard disk

Support and Help
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1

Ubuntu Version:
22.04 LTS (and 24.04.2 LTS)

Problem Description:
My Ubuntu install stopped booting. As far as I know, nothing was being done to the machine on last use, but I cannot guarantee that someone did not just unplug it mid boot or something. Now, when booting, the boot process stops with the following message:

ALERT! UUID=<uuid> does not exist. Dropping to a shell.

BusyBox v1.30.1 (Ubuntu 1:1.30.1-7ubuntu3.1) built-in shell (ash)
Enter 'help' for a list of built in commands.

(initramfs)

I found another thread that starts with the exact same error: Ubuntu 22.04 won't boot (ALERT! UUID=xxx does not exist. Dropping to a shell)

I created a bootable USB stick with Ubuntu 24.04.2 LTS to try the suggestions in that thread. After booting into it, any command referenced in there (fdisk, fschk, parted) do not show the internal hard disk at all. ā€˜disksā€™ also only shows the pen drive.

The weird thing is: using the ACER boot loader, I can still boot perfectly fine into Windows 11 that is installed on the same SSD. It does not complain (except for about not having been updated since 2023). In other words: the disk seems fine. The boot partition may be corrupted, but since the tools that were mentioned do not even find the disk, I cannot check anything.

This is not a critical system so I donā€™t mind formatting or reinstalling Ubuntu. But I am a bit puzzled as to how I would do that if the hard disk is not detected when booting from a pendrive. Any other suggestions to get ubuntu to find the SDD once again would be greatly appreciated.

While creating this post, this topic was suggested to me: Ubuntu 24.04.1 LTS new install drops to busybox, disk not found

The photos of the busybox prompt look almost identical, but in GParted, I just get the USB stick from which I am running Ubuntu right now as /dev/sda*. The internal SDD is not available.

2

At the initramfs prompt type exit: what error messages are displayed?

Please post them here.

3

It repeats the same message:

initramfs
initramfs1600Ɨ900 190 KB

4

Oh, and fwiw: there are no disks in /dev:

dev dir
dev dir900Ɨ1600 192 KB

When I open diskutils in Windows 11, it shows the EFI drive as the first partition (unreadable by Windows, obviously, but it is there).

5

The ALERT errror means grub is looking for the boot files on a Linux partition with that specific UUID and it does not exist. When you boot into windows and go to Disk Management, do you see the Ubuntu partition? You wonā€™t likely see any information on it other than ā€˜Healthy Diskā€™, does that show?

When I do ls /dev/ on Ubuntu 22.04, I show similar output but it shows my SSD drive (nvme0n1) and partitions in the center column of 5 columns while your output only shows 4 columns?

If you donā€™t see the drive from the Ubuntu USB with the standard commands (fdisk -l, parted -l, blkid, lsblk) then I would not expect to see anything in ls /dev.

Were both Windows and Ubuntu UEFI installs? When you access the BIOS boot options, do you see the Ubuntu entry? You might check setting in the BIOS for anything that looks unusual.

6

Yes. It shows, as healthy, but as you said, no other information (nor would I expect more information).

Iā€™m assuming that the number of columns is just because I have fewer devices than you do, but I would expect the SDD to be there. I hadnā€™t considered that it could have a different name than /dev/sdaX, but I do not see anything that triggers me into thinking it might be the SDD or any of its partitions.

Yeah, when I go to the Acer boot menu, I am presented with ā€œubuntuā€ and ā€œWindows Boot Managerā€

Boot Menu
Boot Menu1600Ɨ900 99.1 KB

I donā€™t see anything ā€œstrangeā€ in the BIOS, but then Iā€™m also not sure what is normal and what is strange. Nothing looks out of place with regards to the boot order, for example.

7

Lets get a copy of the Summary report from Boot-Repair. Just post link, hopefully it sees drive, or else report will not show anything useful.

Please copy & paste the pastebin link to the BootInfo summary report ( do not post report), do not run the auto fix till reviewed. Use often updated ppa version with your USB installer or any working install over somewhat older ISO.
Boot-Repair - Community Help Wiki &
https://sourceforge.net/p/boot-repair/home/Home/

8

Here is the link to pastebin: Ubuntu Pastebin

9

Very unusual.
There is no sign of the internal disk in the boot-repair report.
Nor does it see Windows 11 OS.
This leads to questions about the UEFI settings or the firmware itself.

Have you had an Acer Firmware Update from somewhere like https://www.catalog.update.microsoft.com/Search.aspx?q=ACER%20System%20Firmware%20R01-A4

Can you access the UEFI settings and disable any security settings e.g.

  • Encryption/protection
  • Hard disk password
  • Secure boot
  • TPM (or any variants such as ftpm, ptt, trust something or other)

Then, run the boot-repair report again to see if the disk is recognised.

11
  • Encrytption/protection: As far as I can tell this was off.
  • Hard disk password: was not set
  • Secure boot: turned off
  • TPM: I can only pick either pTPM or PTT, I have to select one. Picking pTPM turns off PTT, so I turned that and any other TPM related switches off.
    Here is the new link: Ubuntu Pastebin

I did not get any option for a quick repair this time either. As in, I couldnā€™t do any quick fix, even if you hadnā€™t told me to not do that.

Edit: and unfortunately, I do not see much difference in the boot report, even if I am not sure what I would be looking for.

Edit 2: Oh, as for updating the BIOS, I havenā€™t and I donā€™t think it happened automatically either. Iā€™m not sure if you mean that I should update the BIOS, or that I should not.

12

Do you know if the drive is SATA or NVMe?

Was Windows installed in RAID mode?

Check BIOS for something like storage configuration, does it show RAID or AHCI?

If you are still on the live USB or can reboot again open a terminal and show us the output from this command:
ls /sys/block/

1 Like
13

Itā€™s an NVMe SSD (Kingston OM8PDP3512B-AA1)

Windows is whatever the standard OEM install is, so I donā€™t think itā€™s RAID. Iā€™m a bit out of my depth about the hardware settings in the BIOS, but there is an option ā€œOnboard SATA Modeā€, which is set to ā€œIntel RSTā€, where the alternative option would be AHCI.

Here is the output for the command:

ubuntu@ubuntu:~$ ls /sys/block
loop0  loop10  loop12  loop14  loop3  loop5  loop7  loop9
loop1  loop11  loop13  loop2   loop4  loop6  loop8  sda
ubuntu@ubuntu:~$

Iā€™m pretty sure that sda is the USB stick. If I run the same command at the (initramfs) prompt, I get

(initramfs) ls /sys/block
loop2  loop5  loop7  loop0  loop2  loop4  loop6  loop1
(initramfs)
14

I would change to AHCI in the BIOS but make note of what you did to make the change so that if it does not help you can change back.

Are you able to mount to access the EFI partition from windows to view the contents as you do in Linux? In Ubuntu/Linux, you can view the files for Ubuntu and windows. I donā€™t know if that works in windows but the page at the site at the link below gives one explanation. Havenā€™t used it myself soā€¦?
https://superuser.com/questions/662823/how-do-i-mount-the-efi-partition-on-windows-8-1-so-that-it-is-readable-and-write

1 Like
15

More info here https://discourse.ubuntu.com/t/ubuntu-installation-on-computers-with-intel-r-rst-enabled/15347

16

Okayā€¦ so if i understand the article about RAID correctly, Iā€™ve pretty much just been lucky that it has worked for as long as it has?

I will try mounting the EFI partition as @yancek suggests and see if there is something to do while keeping the current installation. But reading about RAID sounds like i should really try to get windows to not use it any longer and go for the AHCI setting.

It will have to wait until tomorrow. It does sound like a project that is best not started after 10pmā€¦

17

If you use the suggestions at the link I posted earlier, you do not need the commands related to explorer.exe as that is only if you want to access and write to the partition using Windows File Explorer. What you can easily do is use the windows Menu/Start icon in the lower left and open it, go to Windows Powershell, left click and there will be several options below so right lick on Windows PowerShell(x86) and you will see an option to Run as Administrator. This opens the PowerShell window and type each of the commands below, hit the Enter key after each line:

diskpart
list disk
select disk 0
list partition
select partition 1
assign letter=B
exit
```If you have only one physical disk it should be disk 0, your EFI partition for the list partition is probably 1 but you need to verify that.  When you assign letter you can choose whatever you want as long as it is not currently used.

If these commands work for you (I just tested it on windows 10 and it worked), you can look at the EFI partition to see if the ubuntu folder with its EFI files are there.  Either of the two commands below should work:

dir B:\EFI
ls B:\EFI

Either should show the folders on the EFI partition, Microsoft and ubuntu.  If those files are there, you know it is not a problem with EFI files and if it is not an AHCI problem, it is likely .someone/somehow deleted your Ubuntu partition.
18

Microsoft does have a system for BIOS/UEFI updates
https://learn.microsoft.com/en-us/windows-hardware/drivers/bringup/windows-uefi-firmware-update-platform

Yes, certainly possible - until an unknown Microsoft UEFI upgrade changed a setting i.e. re-enabled RST.

Do you remember if you disabled RST when you originally installed Ubuntu?

To err on the side of caution, you could change the Sata mode to AHCI and run the boot-repair report again.
Hopefully, it will be more comprehensive this time?

19

Windows updates may include an UEFI firmware update also. And that often resets UEFI to defaults. If you change settings, you have to redo them.

My newer Dell only needs Windows fast startup & bitlocker off. It even worked with RAID on using the Intel VMD driver in Ubuntu. I actually forgot to change to AHCI when first installing and it worked. At that time I had never heard of the VMD driver. But it has been available in the kernel for a while, but I think Ubuntu did not include it until about 22.04.

If you change to AHCI, you have to also change Windows to use a AHCI driver.
Windows AHCI instructions - some have found safeboot method better
https://www.dell.com/community/Laptops-General-Read-Only/Dell-M-2-FAQ-regarding-AHCI-vs-RAID-ON-Storage-Drivers-M-2-Lanes/td-p/5072571

20

@yancek It seems towork for my Windows 11 as well, and EFI is actually there (using B for anything but a floppy drive felt so weird :smiley: )

Copyright (C) Microsoft Corporation.
On computer: CIAB

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
  Disk 0    Online          476 GB      0 B        *

DISKPART> select disk 0

Disk 0 is now the selected disk.

DISKPART> list partition

  Partition ###  Type              Size     Offset
  -------------  ----------------  -------  -------
  Partition 1    System             260 MB  1024 KB
  Partition 2    Reserved            16 MB   261 MB
  Partition 3    Primary            237 GB   277 MB
  Partition 4    Recovery          1024 MB   238 GB
  Partition 5    Primary            121 GB   239 GB
  Partition 6    Unknown            116 GB   360 GB

DISKPART> select partition 1

Partition 1 is now the selected partition.

DISKPART> assign letter=B

DiskPart successfully assigned the drive letter or mount point.

DISKPART> exit

Leaving DiskPart...
PS C:\WINDOWS\system32> dir B:\


    Directory: B:\


Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
da----         1/11/2023   4:55 PM                EFI


PS C:\WINDOWS\system32> dir B:\EFI


    Directory: B:\EFI


Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
d-----         1/11/2023   4:55 PM                ubuntu
d-----         9/19/2022   6:35 PM                Microsoft
d-----         1/11/2023   4:55 PM                Boot
d-----         1/11/2023   3:43 PM                OEM


PS C:\WINDOWS\system32>
21

Hmm. So I hadnā€™t used Windows on this machine pretty much since I installed Ubuntu. This machine is supposed to work as a demo server for our product, for conferences where we cannot rely on the internet being available. I left Windows on it in case we wanted to use the machine for other things the other 45 weeks of the year, but it turned out that we could do everything we wanted on Ubuntu anyway. Yesterday was literally the first time I ran Windows in over 2 years, and it had certainly not had a chance to update itself in that time. The problem must have started without Windows changing anything. But as I left Windows logged in when I went for lunch, it thought to start updating there and then. So now it is updated. I hope that does not compound the original problem, but it is what it is :confused:

I am 95% sure that I did not touch any other settings than boot order and I think I had to turn off fast boot to make sure that Ubuntu would always reliably start without a keyboard, mouse or screen attached (we run it completely headless when demoing)