Everything. If you can find a better product for the price (free), please leave a comment and a link in Talkbacks. Actually, if you can find something better for under $100US, enlighten me with a name and a link. I've used VirtualBox since the Innotek days. Sun bought Innotek in 2008 and I was unshaken. In 2010, Oracle purchased Sun, and although I was shaken, I was not repulsed. I've stuck with VirtualBox through it all and am glad that I have. VirtualBox is my favorite free, cross-platform, desktop-level virtualization product. Ever.
I've used everything else and still, VirtualBox (VB) is my chosen desktop virtualization software. Although VB isn't perfect, it's the best solution I have.
But, what is it about VB that makes it so great?
Other than simple brags of its coolness, here is a lengthy but incomplete list of VB's hard facts and features.
VirtualBox is a Type 2 hypervisor. That is to say that it is virtualization host software that runs as an application on an established operating system. Alternatively, a Type 1 hypervisor is host software that runs on what's now known as "bare metal," a term that means onto a computer without an operating system. Type 1 hypervisors examples are Hyper-V, ESX/ESXi, Xen, XenServer, KVM and OpenVZ.
To illustrate further, Type 1 hypervisors run cloud-hosted environments, server virtualization environments and virtual desktop infrastructure (VDI) installations. Type 2 hypervisors run on local systems, usually desktop computers, to run a single guest VM.
But, why would anyone use a Type 2 hypervisor if Type 1 hypervisors exist? The answer is simple: convenience. It's convenient for me to fire up a Linux VM, when I need to perform some task, test a script, write an article using something other than Ubuntu, use Windows or to expand my knowledge of another Linux distribution.
I don't have to reboot my current system to an alternate operating system installation, I don't have to maintain expensive Type 1 hypervisor systems nor do I have to keep a dozen different computer systems in my garage. VirtualBox is convenient. It's fast. It's free. It is as the Mac people frequently state, "It just works." And, that, my friends, is a good thing.
What isn't perfect about VB, you ask? On installation, it disables your network interfaces, which should be a temporary inconvenience, but often results in a few reboots or power downs and some frustration. This only happens on Windows systems. I've never had any issues on Linux.
The other slightly annoying feature is that when you create a new VM, the default networking option is NAT (Network Address Translation), which for most people is probably OK but not for me. I like to use the Bridged option, assign a specific network interface type and sometimes use static IP addresses for my "permanent" virtual machines. Often, I'll boot up a new machine, realize that I haven't changed the network setup to Bridged, utter (shout) a list of curse words, power down the VM, make the changes and boot up.
It would be nice if I could change those networking options while the VM is running.
Other than those two minor annoyances, VirtualBox gives me everything I need in a desktop Type 2 hypervisor. Now you know why VirtualBox does not suck.
Do you use VirtualBox for your desktop virtualization software? Write back and tell me why or why not.