VirtualBox on Ubuntu for Running Other Operating Systems

VirtualBox creates a separate computer inside Ubuntu, letting you install and use Windows, Fedora, Linux Mint or another guest operating system without replacing the host. This arrangement is useful for testing software, rehearsing a migration or running a program that does not support Linux. The guest receives its own virtual disk, memory allocation and network settings, while Ubuntu remains available for everyday work.

For many Australians, that separation solves a familiar problem: the main office computer may run Windows while an Ubuntu system handles development or support work. The setup is handy in Sydney, Melbourne, Brisbane, Perth and Adelaide, where a spare laptop can become a test bench without buying another desktop. Current local hardware ranges from Intel Core and AMD Ryzen systems to Apple Silicon Macs. Before choosing a guest, check processor support in the current VirtualBox release; macOS also carries Apple licensing restrictions on non-Apple machines. Guest ISOs can be several gigabytes, so an NBN connection is convenient while regional fixed-wireless or satellite users may prefer wired transfer.

Installing VirtualBox on Ubuntu

Start with the host. For 64-bit guests, use an x86-64 processor and enable hardware virtualisation, called VT-x on Intel and AMD-V on AMD. If a 64-bit guest refuses to start, check the BIOS or UEFI settings and update the host firmware. A recent Ubuntu release with at least 8 GB of RAM is a comfortable starting point, and a 64-bit CPU matters when installing a 64-bit guest.

Ubuntu normally provides VirtualBox packages that match its kernel, so install them from the distribution rather than combining packages from several repositories. Run sudo apt update followed by sudo apt install virtualbox virtualbox-dkms virtualbox-extpack. Package names can differ slightly between releases; if the extension-pack package is unavailable, install the base package and obtain the matching extension pack through Oracle’s official instructions.

Launch VirtualBox from the applications menu or with virtualbox. With Secure Boot enabled, a kernel update can temporarily prevent the DKMS driver from loading, so use current signed Ubuntu packages and a matching kernel instead of disabling protection. USB access is controlled through the vboxusers group on many Ubuntu installations. If needed, add the account with sudo usermod -aG vboxusers "$USER" and sign out before signing back in.

Creating a Virtual Machine

Click New in VirtualBox, choose the guest type and version, then assign resources. Two virtual processors and 4 GB of RAM suit a light Linux guest; Windows 11 benefits from 8 GB when the host can spare it. Avoid giving the guest more than roughly half the host memory, because Ubuntu still needs room for its desktop and applications. For Windows 11, choose UEFI and enable Secure Boot and a virtual TPM where the host and current VirtualBox release support them.

Create a dynamically allocated VDI disk; 60 GB is a practical Windows starting point, while a lightweight Linux distribution may need 25–40 GB. Dynamic files grow as the guest writes data, making them more flexible than reserving the full amount immediately. Set the guest locale to English (Australia), choose the actual keyboard variant and select the relevant Australian time zone. Victoria, New South Wales and South Australia observe daylight saving, so automatic host-to-guest time synchronisation is valuable.

Select an ISO from the operating system’s official download service and verify its published SHA-256 checksum before mounting it. When choosing among many possibilities, a curated list removes guesswork; a Toronto sunset picnic guide does that for an afternoon outing. The equivalent for a guest OS is the vendor’s exact release, architecture, edition and checksum. Avoid random mirrors and copies supplied through chat forums.

Installing the Guest and Guest Additions

Start the virtual machine and follow the vendor’s installer. Use the whole virtual disk when offered, as a small unallocated area can become awkward later. Create the guest account, apply updates and install the software needed for the task. A newly installed guest is a clean test environment, so resist copying personal files across before checking how it behaves.

Guest Additions provides better mouse handling, display scaling, shared folders and clipboard integration. In an Ubuntu or Debian guest, first install sudo apt install build-essential dkms perl linux-headers-$(uname -r). From the VirtualBox menu, choose Devices, Insert Guest Additions ISO, open the mounted image and run sudo ./VBoxLinuxAdditions.run. Restart the guest when prompted. In Windows, run VBoxWindowsAdditions.exe from the mounted image instead.

After the reboot, test mouse capture, clipboard copying and resizing before moving files. For a shared folder, add the guest account to the vboxsf group with sudo usermod -aG vboxsf "$USER", then sign in again. Use an Extension Pack and Guest Additions release compatible with the installed VirtualBox version to avoid missing features or kernel errors.

Sharing Files, Networking, and Devices

The default NAT mode gives the guest internet access through the host while keeping it away from the local network. Bridged mode attaches the guest directly to the home or office LAN, which is useful for server testing but exposes its ports to nearby devices. Host-only networking permits communication between host and guests without internet access. With the guest’s SSH server running, forward host port 2222 to guest port 22 and connect using ssh -p 2222 user@127.0.0.1.

Shared folders are convenient for moving installation media and documents between Ubuntu and the guest, but they are not a substitute for a network file server. Decide whether access should be read-only, and avoid exposing an entire home directory when a smaller project folder will do. Guest Additions normally mounts the folder under /media/sf; if the mount is missing, check that vboxsf is installed and that the guest user belongs to vboxsf.

USB devices can be attached to one guest at a time through the Devices menu, which suits an external SSD, security key or phone. Australian buyers often pair compact computers with USB-C docks and external NVMe drives, so test those attachments before relying on the VM daily. If the virtual disk is stored on an external drive, do not pass that drive into the guest because the host may lose access to it. Set the guest resolution to match the actual monitor and keep printer, audio and webcam choices deliberate.

Security, Performance, and Recovery

Treat every ISO as external input: download it from the vendor, compare its checksum and scan it if the source is uncertain. A guest can affect shared folders and clipboard data, so disable those features while handling sensitive material. Keep Ubuntu, VirtualBox and Guest Additions patched, and remember that a Windows guest requires its own valid licence. The extension pack also has separate Oracle terms, including free personal and evaluation use.

Virtualisation reduces accidental damage to the host, but it does not make every guest action harmless. Snapshots let you return to a clean state after testing a configuration, yet they consume space and are not backups. Keep the virtual disk in the host’s regular backup routine, export important guests occasionally and avoid filling the host filesystem with old snapshots.

For smooth performance, leave host storage free, assign only the resources the guest needs and update the guest kernel so integration modules match it. Dynamic disks and hardware virtualisation are usually enough for office tasks. Suspending rather than shutting down can restore a session quickly, although a full shutdown occasionally clears stale locks. Back up the guest before changing disk size, networking or a major VirtualBox release.

For Linux-only guests, native KVM with Virt Manager can integrate more closely with Ubuntu and may suit a dedicated test machine. UbuntuNext’s KVM and Virt Manager guide explains that alternative and the setup choices involved. VirtualBox remains valuable when you want one interface for several operating systems, USB pass-through and portable virtual disks between compatible x86 hosts.

By the time the guest is useful, the important work happens outside the installer. Resources are balanced, Guest Additions are running, networking matches the purpose, shared data has a deliberate path and a recovery point has been created. Those checks turn an experimental operating system into a repeatable tool for work that would otherwise force a reboot, a second machine or a risky change to the Ubuntu desktop.

The lasting lesson is that VirtualBox works best as a controlled workshop beside Ubuntu. Trusted media, an updated guest, preserved host performance and a clear recovery route are what turn the exploration of Windows or another Linux distribution into a measured technical task rather than a gamble with the computer used for daily work.