Darren New wrote:

> The other thing people use snapshots for is so they can either try 
> something that might break things, or to make the vdisk back-up-able 
> while it's running.

I'm not planning to do any "work" with a VM, just testing. Stuff like:

- What happens if I open this file with Office 2007?
- I need a Linux box to quickly do some stuff.
- What happens if I install this random untrusted program I just found 
on the Internet? (But I don't want to *really* install it, or sign and 
date a legally-binding record stating that I installed it...)

>> Apparently there's an opion when creating the VM that asks if you want 
>> a single disk image or multiple such.
> 
> That's it.

Our VMware "expert" claims that pre-allowating the HD image can result 
in reduced load on the HD subsystem (obviously at the expense of more 
disk space eaten).

> You're aware that Vista and later comes with a free (but incompatible 
> with VMWare) VM system, right?  See if you have a program called 
> "virtual PC" around.

I hear that Windows 2003 Server (?) comes with a "hypervisor" which runs 
on the real metal, and then 2003 itself actually runs as a 
paravirtualised guest. Or something like that...

>> I was wondering if the VMtools it installs would provide a way to do 
>> this... but if it does, I don't see one. As for compression... does 
>> VMware not do that itself anyway? The snapshots look a *hell* of a lot 
>> smaller than the main disk image... (Like, less than 1GB each.)
> 
> They're just not allocating the space in advance. I was talking about if 
> you *do* allocate space in advance, then your *backups* could still be 
> small.

Ah, OK.

Given that the main disk image is 1.5GB but the snapshots are only 300MB 
each, I figured it was doing some sort of compression.

> Also helpful when you tend to unpack a 50G tarfile, do something 
> with it, then throw it away, leaving yourself a 50G empty vdisk file.

Oh, definitely. And that's why I was hoping that the VMware Tools might 
include a tool to zero unused sectors. But apparently not...

Ooo, hey. Crazy idea: I could set up my VM how I want, and then boot 
from the Ghost boot CD and take a Ghost image! It only copies used 
sectors, and has compression built-in.

>> Also... apparently VMware Player can do more than, um, play VMs now? 
>> (I just looked at what it would cost to buy myself a copy of VMware 
>> Workstation, but it's like £150 or something!)
> 
> It's like any other OS. You could run things on a remote machine and 
> control them from your desk, and stuff like that. I'm not really 
> familiar with it.

More annoyingly, to get VMware Player they demand that you register an 
account using a real name, etc.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message