Mounting VirtualBox shared folders on Ubuntu Server 18.04 LTS

This guide will walk you through steps on how to setup a VirtualBox shared folder inside your Ubuntu Server guest. Tested on Ubuntu Server 18.04

Steps:

Open VirtualBox
Right-click your VM, then click Settings
Go to Shared Folders section
Add a new shared folder
On Add Share prompt, select the Folder Path in your host that you want to be accessible inside your VM.
In the Folder Name field, type shared
Uncheck Read-only and Auto-mount, and check Make Permanent
Start your VM
Once your VM is up and running, go to Devices menu -> Insert Guest Additions CD image menu
Use the following command to mount the CD:
```
sudo mount /dev/cdrom /media/cdrom
```

Install dependencies for VirtualBox guest additions:

sudo apt-get update
sudo apt-get install build-essential linux-headers-`uname -r`

Run installation script for the guest additions:
```
sudo /media/cdrom/VBoxLinuxAdditions.run
```
Reboot VM
```
sudo shutdown -r now
```
Create "shared" directory in your home
```
mkdir ~/shared
```
Mount the shared folder from the host to your ~/shared directory
```
sudo mount -t vboxsf shared ~/shared
```

For set custom group and user id owner

sudo mount -t vboxsf -o  uid=1000,gid=1000 shared ~/shared

The host folder should now be accessible inside the VM.
```
cd ~/shared
```

Make the mount folder persistent

This directory mount we just made is temporary and it will disappear on next reboot. To make this permanent, we'll set it so that it will mount our ~/shared directory on system startup

Edit fstab file in /etc directory
```
sudo nano /etc/fstab
```
Add the following line to fstab (separated by tabs) and press Ctrl+O to Save.
```
shared  /home/<username>/shared vboxsf  defaults    0   0
```
Edit modules
```
sudo nano /etc/modules
```
Add the following line to /etc/modules and save
```
vboxsf
```
Reboot the vm and log-in again
```
shutdown -r now
```
Go to your home directory and check to see if the file is highlighted in green.
```
cd ~
ls
```
If it is then congratulations! You successfully linked the directory within your vm with your host folder.

2019-02-03 13:20:00