How to Mount VirtualBox Disk Image (VDI) to Access VM File-System in Ubuntu

Last updated: May 28, 2021 — 6 Comments

This tutorial shows how to mount the VirtualBox virtual disk image in Ubuntu, so you can access the Guest OS file system with read and write permission, if it does not boot.

After misconfigured my VirtualBox Guest OS, it does not longer work. I know how to correct the issue to make it boot again, but firstly accessing to the file system is required!

Since the VBox user manual does not work, here’s what I did in Ubuntu 20.04 host with VirtualBox 6.1.x:

Before getting started, make sure Guest OS is shutdown. And the disk image is not in use. Also UN-MOUNT the disk once the job done.

1.) Firstly open terminal from system application launcher. When it opens, run command:

vboximg-mount --list

vboximg-mount is a utility to make VBox disk images available to the host. With --list, it list all Disk Images as well as the UUID.

In the case, I have all Guest OSes on single Disk Image (.vdi). And the uuid is: “3db5fd91-fd56-46af-a2d2-98cd62b05ea3”

2.) Next perform a FUSE mount of the virtual disk image:

First create a folder as mount point, vbox_sysdisk for instance:
```
mkdir vbox_sysdisk
```

Then mount it via command (remember to change the UUID to yours):

vboximg-mount -i 3db5fd91-fd56-46af-a2d2-98cd62b05ea3 -o allow_root vbox_sysdisk

NOTE: You may need to edit the “/etc/fuse.conf” to make the -o allow_root flag work. To do so, run command sudo gedit /etc/fuse.conf and enable (remove # at its beginning) “user_allow_other” line.

3.) As the previous picture shows, I have 5 disk partitions: vol0, vol1, …, vol4. Now mount either partition (vol4 for instance) to /mnt via command:

sudo mount vbox_sysdis/vol4 /mnt

Finally go to /mnt directory and there you are.

Unmount:

To un-mount the guest os file system, run command:

sudo umount /mnt

To un-mount the VBox disk image, run command:

umount ~/vbox_sysdisk

And you may finally remove that folder either from file manager or by running command in terminal:

rm -r ~/vbox_sysdisk

In Howtos Virtualbox

Ji m

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I'm a freelance blogger who started using Ubuntu in 2007 and wishes to share my experiences and some useful tips with Ubuntu beginners and lovers. Please comment to remind me outdated tutorial! And, notify me if you find any typo/grammar/language mistakes. English is not my native language. Contact me via [email protected] Buy me a coffee: https://ko-fi.com/ubuntuhandbook1

6 responses to How to Mount VirtualBox Disk Image (VDI) to Access VM File-System in Ubuntu

Beyersdorff October 11, 2021 at 9:34 pm

Alright but I guess using guestmounts/.vhd instead of vboximg-mount/.vdi maybe less fiddly.

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Mark Spychalski October 28, 2021 at 7:50 pm

Nie działa
vboximg-mount –list
vboximg-mount: nie znaleziono polecenia

Reply
ajcg November 3, 2021 at 4:57 pm

You should have started the post explaining how to create the image by command line before mounting it. Because as you explain it it does not work

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lino May 3, 2022 at 9:54 am

Thanks for sharing. But must advise that mounting like this is not the same as editing. If you use vmbox-mount and make-changes, it wont affect the vdi file. Just the mounted folder.

Reply
chenny August 4, 2022 at 7:53 am

To mount read/write, add –rw option (needs VB 6.1.36 at least)

Reply
Thomas Stadtmüller April 23, 2023 at 8:06 am

Thank you, Ji m!
The instructions work like a charm on Ubuntu 22.04.2 LTS.
Problem: after installing the VirtualBox 7.0.8 r156879 extension pack on a XP machine, it would start-up only with black/blank display; i.e. unusable. To fall back to a back-up vdi, I needed a few (newer) data files from the unusable vdi.
Thomas

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