[SOLVED] Another lost password post - help with accessing a vm/guest

[NevadaTech]

Hello,

I have a vm/guest that the password listed does not work. Sigh. This is the guest not the host. The guest is an Ubuntu 22.04 server. Proxmox 8.1.10

The normal process of boot into single user mode then resetting passwd should work, but...
the guest boots too fast. I cannot use the Shift key and I never see a grub screen to edit

I did try to boot with an Ubuntu Desktop ISO, then terminal, then hoped to mount the drive but no joy. It shows the disk as a GPT and 'not a valid NTFS' error message comes up when I 'mount /dev/sda1 /mnt/recover'

There doesn't seem to be a BIOS I can access to set a wait time before booting. My hope there is to try to press the shift key before the dang thing starts.

 

[leesteken]

Can you show the gdisk -l /dev/sda or lsblk /dev/sda output of the VM when booted with the Ubuntu installer (or similar) ISO? Maybe the root partition is not the first (/dev/sda1) but the second or maybe there is a LVM in between.

 

[NevadaTech]

here's a pic of the output

 

[NevadaTech]

and one with the
lsblk /dev/sda

 

[leesteken]

/dev/sda1 is the GRUB partition for the bootloader.
/dev/sda2 is probably the /boot partition.
/dev/sda3 is indeed a LVM which contains one or more logical volumes, one of which is the root parition you want.
I don't know Ubuntu well enough to tell you what to do but there must be many guides on the internet that can help you, as this is not specific to Proxmox or virtualization. If this was a physical machine, you would follow the same steps. Maybe this one can help: https://bytefreaks.net/gnulinux/how-to-reset-password-on-an-ubuntu-with-lvm

 

[NevadaTech]

I believe you are correct about the LVM.

Hah! I was searching for a fix and wound up on the same bytefreaks page.

 

[NevadaTech]

This fixed things. Thanks Lee for pointing me to check for the LVM.

For others, if you follow the bytefreaks instructions, they mostly work. After the

passwd -S bob;

this gets you the (S)tatus of the user's passwordd; then follow that up with a

passwd bob;

to actually set your password