Access data on a vdisk that won't boot

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Access data on a vdisk that won't boot

Operating system
  1. Linux
Mobile operating system
  1. iOS
TL;DR: "How do I mount/open a vdisk for a VM that doesn't boot?" I want to access files directly from inside the vdisk without it running the VM that was on it. I don't care if I have to access it from Synology NAS CLI or if I have to copy the vdisk image to my local machine to do so.

More details:

I was working on an Ubuntu VM I had running on a DS918+

In the course of things I ended up destroying the /boot partition and unsurprisingly when I rebooted the VM it doesn't boot (duh) and instead goes to grub rescue> . I don't have a snapshot/backup of the VM.

This is the original structure of the VM was:

loop0 squashfs 55.4M /snap/core18/1944
loop1 squashfs 55.5M /snap/core18/1988
loop2 squashfs 69.9M /snap/lxd/19188
loop3 squashfs 70.4M /snap/lxd/19647
loop4 squashfs 32.3M /snap/snapd/11402
loop5 squashfs 32.3M /snap/snapd/11107
sda 600G
├─sda1 1M
├─sda2 ext4 1G /boot <<<--- got damaged **
└─sda3 LVM2_member 599G
└─ubuntu--vg-ubuntu--lv ext4 598G /
sdb 100G
└─sdb1 ext4 93.1G /media/hhd100GB
sr0 iso9660 1.1G Ubuntu-Server 20.04.2 LTS amd64
sr1 1024M

(** due to some bad fat-fingered 'mount' commands that cause another volume to mount to /dev/sda2 instead of where it should have. )

In any case, what I'd like to do is be able to be able to open the vdisk I found in


On the 918 NAS. It is identified as: vdisk.9cebd384-cd62-4b68-a672-20dae3feedc9.7dedb7ff-fd41-4706-9d7d-63af11fa6636.2.0_00000

From that vdisk I want to access some of the directories on /sda/sda3/ LVM2_member/ubuntu--vg-ubuntu--lv in order to retrieve some materials before I 'start over' and rebuild from scratch. (I ~~think~~ I have everything backed up that was important to my local laptop, but I want to be able to double check since the VM held the most recent tweaks to some code) Ideally I would like to be able to navigate to something like "/mnt/vdisk/sda3/var/www/vhosts/" and recover files from the "" directory.

I've never done this before, but some part of me thinks there must be a way to 'mount' the various partitions contained in the vdisk without actually booting the OS on the vdisk itself.

Of course, if there's something even easier than what I've explained, I'm all ears on that too. (I'm kind of wondering if I can boot from that Ubuntu ISO listed at sr0 and accomplish sort of the same thing)

Thank you in advance for any help you can provide.

Were you able to mount the corrupted VDISK? I have the same question and the same problem.
With other VDISK I was able to access them with the application Virtual Machine Manager for Linux and it is the same application like the one used in Synology. But mine won't boot.

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