Virtual appliances: I don't see the point

[_leech_]

I get the basic idea behind a virtual appliance - take something you'd build a separate computer for and virtualize it, saving on space, noise, and power - but some of these uses seem really impractical.

Take a NAS, for example. I've seen NAS's listed as a great use for a virtual machine from a few sites, but it confuses me. One of the better reasons why you have a NAS in the first place is to have storage outside of your PC that's relatively secure in case something happens to it. And hey, stick two or three drives in the thing and you'll have data redundancy, too. So why the hell would you virtualize it? What good is a RAID-5 NAS if it's sitting on one hard drive?

Another example, a LAMP server. What good reason is there to run this as a virtualized machine as opposed to building a local *AMP setup on the local machine? Or using XAMPP?

The biggest problem I see is that you'd basically be consolidating a couple of computers into one single point of failure, and that makes no sense to me. Or maybe i'm just missing the point? Someone point me in the right direction, please.

 

[vertigomhs]

im not sure if im understanding correctly :|

with VT you can multiple OS's on one machine, this can be used to run lets say vista and xp on the same machine and have them running at the same time while being able to switch in between.

also VT is also good for servers, lets say you dont have enough money for a full server, so what server owners do is make a VPS (virtual private server) in which they use VT to run lets say 5 different OS's on one machine in which they all pay a small fee to add up to the big full server fee. They dont get the full benefits of just a full server and they have to share the servers resources in between each other.

 

[H6195]

"What good is a RAID-5 NAS if it's sitting on one hard drive?"

I'm not following what you are saying. If the NAS is using RAID 5 and stores virtual machines, then the machines are striped with distributed parity, no?

Wouldn't the advantage be to have a secure, safe location for the machines while allowing multiple departments to access them without having them isolated on one domain (or to one department in an office)?

Correct me if I'm wrong here, I'm just visualizing why someone would implement it this way.