Virtual Machine questions

[Jeff7181]

Have a few questions, hopefully I can get some answers to them.

First... to those who have experience with them, is there a performance difference between different software like Virtual PC 2004, Virtual Server 2005, or VMware?

Second... since one of the benefits of a virtual machine is the ability to test new software before deploying it, is it possible to customize a virtual machine to emulate specific hardware? For example, a specific model/chipset NIC or a specific mouse? Or is it more for testing software compatability with other software and OS's?

Third... my schooling will focus mainly on Virtual PC 2004... will things I learn about that apply to the other software I mentioned?

 

[itachi]

you don't need to run a server..

1. yea.. there is a performance difference. vmware is faster, but more expensive.
2. no, you can't get it to emulate specific hardware.. and vms don't emulate, they virtualize.
3. if you're talking about using the software, then no.

 

[xtknight]

1. Parallels workstation seemed slower than VMware, that's from my friend's experience. I'm sure some are more optimized than others.

2. Theoretically it probably would be, but you can't run an OS with an architecture other than your own with these programs. It may be possible somehow (not with virtualization programs). When I wanted to test an SMP program, VMware wouldn't let me enable two CPUs in the options.

3. If it's learning about virtual machines themselves, sure. Most of them let you mount either an ISO or real physical disk for a virtual CD-ROM, most let you write to a floppy image. All of them 'enclose' the operating system in a reasonably safe environment, unless given access to hardware that could do harm. You can disconnect their network access, etc. They all have lots in common except for the user interface. Most of the time you won't even need to touch the virtualization program itself. The guest OS should act virtually (no pun intended) identical across VMs.

 

[Nothinman]

Second... since one of the benefits of a virtual machine is the ability to test new software before deploying it, is it possible to customize a virtual machine to emulate specific hardware? For example, a specific model/chipset NIC or a specific mouse? Or is it more for testing software compatability with other software and OS's?

Not really, the VM software presents a specific set of hardware and you can't really change it. And it wouldn't be a valid test for drivers anyway because real hardware tends to differ from how the docs say it should work anyway.

Third... my schooling will focus mainly on Virtual PC 2004... will things I learn about that apply to the other software I mentioned?

The basic ideas will be the same but the methods, terminology, etc of each product will be different.

 

[Jeff7181]

Originally posted by: itachi
you don't need to run a server..

1. yea.. there is a performance difference. vmware is faster, but more expensive.
2. no, you can't get it to emulate specific hardware.. and vms don't emulate, they virtualize.
3. if you're talking about using the software, then no.

Maybe you were reading more into my questions... why do you say "you don't need to run a server?"

 

[itachi]

Originally posted by: Jeff7181

Originally posted by: itachi
you don't need to run a server..

1. yea.. there is a performance difference. vmware is faster, but more expensive.
2. no, you can't get it to emulate specific hardware.. and vms don't emulate, they virtualize.
3. if you're talking about using the software, then no.

Maybe you were reading more into my questions... why do you say "you don't need to run a server?"

goddamnit.. i keep on missing sht.
forget what i said.. i don't think i was reading your question at all heh.

and before someone corrects me.. for 2., before ms bought out virtual pc.. it emulated an x86 proc on osx.

 

[Jeff7181]

So, am I right in saying virtual machines would be more useful for software engineers than network engineers?

I have Fedora Core 5 running in a virtual machine right now, and I'm not impressed with the performance of simple things like opening applications and stuff... although I haven't installed it in a dual boot configuration so I don't really know what kind of performance is "normal."

From what I've been hearing from people, virtual servers and virtual machines are supposed to be "the next big thing" but if performance suffers as much as it appears to, I can't see it being a viable solution in a professional environment for anything but testing old software before deploying a new OS or something like that.

 

[itachi]

So, am I right in saying virtual machines would be more useful for software engineers than network engineers?

for development.. it's useful when you need to test out an application on a different platform.
a network engineer probably wouldn't find it useful for their own purposes, but an organization may.

what vm are you using? i'm running rhel3 in vmware workstation 4.5 on win xp, and the performance and response is about the same as with a real boot.

 

[xtknight]

Fedora Core 5 ran great in my Ubuntu VMware. Things (documents and programs) opened faster than my Ubuntu (dare I say that), but it was a fresh install.

 

[Jeff7181]

My Fedora installation is running on Virtual Server 2005.