The Register® — Biting the hand that feeds IT

Feeds
  • print
  • alert

Customer Success Testimonial: Recovery is Everything

Apple users are familiar with the frustration of finding that some new appendage they've acquired is only supplied with software to communicate with Windows machines. Windows connection software for phones, cameras, or non-iPod MP3 devices should run well inside a Windows virtual machine, although the ultimate solution is to insist on hardware that embraces USB mass storage, and so can transfer data across all operating systems with no special software.

Virtualisation for Beginners

Parallels Desktop's Crystal Mode allows windows from the guest OS to float freely among the host OS' windows. Windows apps - marked with the orange Parallels symbol - are available from the Mac's Dock.

Do you need to power up the whole virtual machine just to run one small guest application? Yes, you do, but you can do this under the covers. Parallels Desktop's Crystal Mode allows windows from the guest operating system to float freely among those of the host operating system, and attaches the guest applications to the host's menuing system. VMWare Fusion takes the same approach with a similar facility called Unity.

In effect, this allows you to encapsulate the guest application and run it as if it were just another host app. If you can spare the memory, you can speed up the process having the guest operating system under the hypervisor ready-loaded at boot time.

The Downside of Hardware Virtualisation

“There is no software-visible bit whose setting indicates whether a logical processor is in VMX non-root operation. This fact may allow a VMM to prevent guest software from determining that it is running in a virtual machine” - Intel VTx specification.

Intel's VM hardware design means that it may be impossible for an operating system to know it's actually running as a guest, not as a host. This is useful, eg. for driver developers, but also allows for the mother and father of all rootkits.

It's been suggested that an operating system simply has to try to load a VM of its own, ie. launch its own hypervisor. If it can't then it's probably running as a VM itself. However, Joanna Rutkowska, the Polish security specialist who conceived the Blue Pill hypervisor rootkit, has shown that nested virtualisation is possible, and an OS capable of launching a hypervisor might still be running under an even higher privileged hypervisor.

In essence, this is the so-called God Problem. Key to atheist Richard Dawkins' argument for the non-existence of God, is the premise that "a world without God would be very different from a world with God". But need there be any detectable difference?

Regcast training : Hyper-V 3.0, VM high availability and disaster recovery

Eh...

"Technically, if perhaps not legally, you can run Mac OS X in a VMWare virtual machine under Windows"

OSX on top of Windows...

Technically, if perhaps not legally, if you were doing that you might need your head examined.

1
0

No need for virtualisation.

You do know you can run multiple instances of WoW (against a single install) already right, without the need for any kind of virtualisation?

I used to run 5 copies (multi-boxing an entire party) on my Mac Pro - just because I could.

0
0

Yes and I have this bridge for sale.

Parallels have been promising graphics card virtualisation for years as a point release for version 3. I fell for it and when a new major release came out, still without the support I declined to give them any more money.

We're now at version 5 and they're still promising.

0
0

More from The Register

Bjarne Again: Hallelujah for C++
Plus: Now officially OK to admit you never used STL algorithms
Interwebs taunt Sir Jony over Apple eye candy makeover
Hey Ive, Ive... add more unicorns, willya?
SCO vs. IBM battle resumes over ownership of Unix
Zombie lawsuit back and wants to suck the brains out of Linux
Red Hat to ditch MySQL for MariaDB in RHEL 7
So long, Oracle! Don't let the door hit you on the way out
Shy? Socially inadequate? Fiddling with your phone could help
App 'tells the brutal truth' about social inadequates' chatup lines
Java EE 7 melds HTML5 with enterprise apps
New release arrives with GlassFish, NetBeans support
 breaking news
'Office Facebook' firm Tibbr wants you to PAY for mobe-meetings app
Great idea. Punters won't cough for it though
 breaking news
The only Waze is Google: Ad giant tipped to gobble map app 'for $1.3bn'
Pac-Man-satnav-ish upstart in bidding war with Apple, Facebook
 breaking news
PM Cameron calls for modern, programmable computers! (We think)
IT education musings to G8 chiefs to mystify IT industry
Apple at WWDC: Sleek new iOS, death of the big cats, pint-sized Mac Pro
CEO Cook: 'The biggest change to iOS since the introduction of the iPhone'