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

Last updated: May 28, 2021


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.


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


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 Please comment to let me know if the tutorial is outdated! 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:

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

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

  2. Mark Spychalski October 28, 2021 at 7:50 pm

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

  3. 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

  4. 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.

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

  6. 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.

  7. Here, by the way, is my own summary of this EXCELLENT article.
    – – –

    1. shut down the guest OS

    2. open terminal

    3. list all disk images and their UUID”s:
    vboximg-mount --list

    4. ensure that user_allow_other in /etc/fuse.conf is not commented out

    5. create a mount point folder:
    example: mkdir vbox_sysdisk

    6. mount the vdi
    vboximg-mount -i -o allow_root
    example: vboximg-mount -i 3db5fd91-fd56-46af-a2d2-98cd62b05ea3 -o allow_root vbox_sysdisk

    7. list the contents of the mount point folder:
    ls / -al
    example: ls vbox_sysdisk/ -al

    8. mount the root volume of interest
    sudo mount / /mnt
    example: sudo mount vbox_sysdisk/vol0 /mnt

    – –
    9. The VDI drive will show up on the desktop. Modify contents as desired, carefully of course
    – –

    10. to thoroughly unmount: first, unmount the guest os file system
    sudo umount /mnt

    11. unmount the vbox disk image:
    umount ~/
    example: umount ~/vbox_sysdisk

    12. remove the mount point folder
    rm -r ~/
    example: rm -r ~/vbox_sysdisk

    – – –
    Your work is just extraordinary, Ji m. I’m a bit tight on $$ right now, but I’ve made a small donation, and shall give more in the future. Thanks SO very much.

  8. auuggghhh. this commenting system is causing those errors in step 8, turning verbiage into a single slash. So, just don’t approve my summary.