Virtual Machines

What is a computer?

Electronic device that gets work (or fun) done

Examples of computers

desktop, laptop, cellphone, other devices

What are computers built from?

Hardware

What runs computer hardware?

OS software

What is a virtual machine?

Software that runs in user space in the existing OS (host OS) as an independent process. It is a virtual environment that emulates a computer system with its own virtual cpu, memory, network interface and storage

What can a VM house simultaneously?

many different OSs (Guest OS)

What does the Virtual Machine Manager do?

It creates and runs your VM by creating a virtual interface identical to the host machine

Other name for VMM?

Hypervisor

What do VMs use to operate?

A computers physical resources

Type 2 VMM

emulates VM and underlying hardware, runs on host OS (Oracle VirtualBox, VM Ware Workstation)

Type 1 VMM

“bare metal”, runs directly on hardware directly without underlying OS

Appliance

A VM setup, pre-configured and packaged in open virtualization format (.OVF) that can be imported or exported

Clone

A copy of the VM on the same machine (different UUIDs)

Snapshot

A backup of the VM. That can restore the VM in case of VM failure

Oracle Virtual Box:

• Computer can run multiple OSs in multiple VMs at the same time.

• Container is a virtual setup that keeps applications isolated from the OS they run on.

• Provides complete isolation from other containers and from the host OS.

• Has its own process and networking, resembles sandbox environment.

  • # of VMs is limited by disk space and memory

• Can be frozen, woken up, copied, backed up, and transported between hosts.

• Free….

History of Oracle VirtualBox

Created by Innotek GmbH, sold to Sun in 2008, then to Oracle in 2010