Adding new partition to the existing Vagrant VM

This will be a tutorial about adding new partition to the existing Vagrant (Virtual Box) machine. It should be safe to follow but please backup your data before proceeding.

Use vagrant-disksize plugin from

Installation is easy

Execute inside you Vagrant VM folder:

vagrant plugin install vagrant-disksize

Then configure

Modify your Vagrantfile according to plugin Usage section:

Vagrant.configure('2') do |config| = 'ubuntu/xenial64'
  config.disksize.size = '50GB'


vagrant up

Now the tricky part

If you are not an experienced Linux user it might be not so easy. You will have to create and format new partition using command line.

Enter your Vagrant box

vagrant ssh

Become root user

sudo su -

Enter partitioning utility

fdisk /dev/sda
  1. Press p to check current partitions table (just for your information)
  2. Press n in order to create new partition
  3. Press e to create extended (logical) partition
  4. Select its number (or hit ENTER to leave the default selection which should be OK in most cases)
  5. Select first sector (or hit ENTER to leave the default number which should be OK in most cases)
  6. Select last sector (hit ENTER to leave the default number which should ensure that entire available space will be used)
  7. Press p and check that you have now a new partition (compared to step 1.)
  8. Press w to save your modifications

After these steps you should see output similar to this one:

The partition table has been altered.
Calling ioctl() to re-read partition table.
Re-reading the partition table failed.: Device or resource busy

The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8).

You shouldn't worry about ...: Device or resource busy message

Exit your Vagrant box


Yes execute it two times: first one leaves root and second one exits Vagrant.

Restart your Vagrant box

vagrant reload

(or vagrant halt and vagrant up if you prefer)

Reenter Vagrant

vagrant ssh

You may check with df -h that your new partition is not currently mounted

Format new partition

Assuming that you new partition is located at /dev/sda3

sudo mkfs -t ext4 /dev/sda3

If it asks you about proceeding Proceed anyway? you should probably answer with y.

Mount your new partition!

sudo mkdir /mnt/new_partition
sudo mount /dev/sda3 /mnt/new_partition

So it is now available on /mnt/new_partition path.

That's it you are done.

Automounting new partition

After setting up new partition you will probably want it to mount on VM startup without need for manual mount.

Check the for info about automount setup using /etc/fstab file.


If you want to play with resizing existing disk please refer to the: and/or (I had no luck with this solution but it might work):