How do I run two (or more) operating systems on the same computer?

There are two main ways to do this: dual-booting, and running a virtual machine.

Dual-booting installs multiple operating systems on separate locations of the harddisk, allowing you to choose between them at boot time.

Virtual machines let you run a a simulated computer, with a real and separate OS, as a software application in the existing host OS.

Dual-booting is a bad idea and you shouldn't do it.

Dual-boot systems are fragile and hard to maintain:

• Managing partitions and boot loaders can be difficult and time-consuming unless you have a lot of experience with it.
• It's easy to break the boot environnment, losing access to one or even both of your operating systems.
• Recovering from a broken boot environment can be extremely difficult, and it's possible to break things even more.
• Sharing files between the two operating systems can be problematic, and one OS can quite easily damage another one's system files.
• Removing an unwanted dual-boot OS can be difficult, and often the disk space can only be reclaimed as a separate drive letter under windows.

For these reasons, CSG strongly recommends against dual-booting your computer.

Also for these reasons, CSG will not help you to repair a broken dual-boot environment.

We can (potentially) rescue your data, wipe the drive and help you install a new single OS, but we can't help with getting both OSes up and running again.

You are free to set up a dual-boot system, but you do so at your own risk.

If you really have to dual-boot

In rare cases - usually when you need direct access to the hardware - you might find you need to dual-boot anyway.

If so, here's some documentation that can get you started:

• Boot Camp for Mac lets you install Windows in a separate partition.
• Most Linux distribtions can set up dual-boot for you - see the (Ubuntu Help page)
• You can also Install Ubuntu in a Windows partition and boot to that.

Virtual Machines

Virtual machines are a much more stable and maintainable way to work with multiple operating systems.

They use a virtual disk partition in a file inside your native operating system, and the software itself runs as a normal application.

File sharing is managed by the application, and is very safe to use.

It's also very easy to install, remove and back up multiple virtual machines, and you can even transfer them to other computers with no problems.

There's a slight extra performance/resource cost on your machine, but this is not very high and is more than made up for by the other benefits.

There are a number of different hypervisors on the market, but the two we recommend are:

VMware

Full-featured commercial product.
CSE has VMWare licenses available for staff and enrolled students - contact System Support to request a license.

Oracle Virtualbox

Slightly smaller feature set, but more than enough for most cases, and completely free to use.
Download from virtualbox.org.

Once you have one of these packages installed, you can download Linux or Windows to install in the Virtual machine.

Alternative approaches

If you just need access to a few bits of software and not a full second operating system, there are some alternatives available:

CSE VLAB

CSE provide a virtualised CSE lab environment

CSE Login servers

CSE provide a number of Linux login servers, for remote access.

Windows Subsystem for Linux

The WSL lets you install a stripped-down Linux distribution directly into Windows 10