What is VMware?

Can anyone thoroughly explain what this is? Yes, I can look it up, but the reason I'm asking here is because from what I understand about it is that it's Virtual Emulation Lab.

Now, dont you use this for "seeing" the utilizations of the servers?
Its not exactly a "lab" per say is it? A lab would just be a virtual "fake" environment that you would use to practice on.

Can anyone thoroughly explain this? I'd appreciate it. Again, I've wikipedia & googled and talked with 1 other techie about this so It's not that I'm being lazy on my research. I was just wondering if one of you smart guys could put this in lamens terms on exactly what it is, what it's used for and why.

Thanks,

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dynamik

DerekAustin26 wrote: »

What is VMware?

It's a company...

DerekAustin26 wrote: »

Can anyone thoroughly explain what this is? Yes, I can look it up, but the reason I'm asking here is because from what I understand about it is that it's Virtual Emulation Lab.

Now, dont you use this for "seeing" the utilizations of the servers?
Its not exactly a "lab" per say is it? A lab would just be a virtual "fake" environment that you would use to practice on.

Can anyone thoroughly explain this? I'd appreciate it. Again, I've wikipedia & googled and talked with 1 other techie about this so It's not that I'm being lazy on my research. I was just wondering if one of you smart guys could put this in lamens terms on exactly what it is, what it's used for and why.

Thanks,

Virtualization != emulation. Honestly, the best way to "get" it is to just work with it. Install VirtualBox or one of the free VMware products and play around. Seeing is believing.

The main draw is being able to run multiple OSes simultaneously on one physical machine.

RobertKaucher

Virtualization technologies allow you to run multiple operating systems on the same hardware simultaneously.

At work I have a server with 2 quad core procs/a load of RAM and hard disk space that are all shared by about 7 virtual "servers". This allows me to keep costs down. One thing is that it is cheaper to buy 1 server with a lot of ram/disk space than it is to buy 7 servers with less RAM/disk space. It also costs less in terms of electricity used.

Using VMWare products (or MS products like Virtual PC or Hyper-V, or Sun's Virtual Box) you can create virtual machines, which "trick" the OS into thinking it is running on its own server hardware.

This also allows you to setup Virtual lab environments. At home I have a system currently running 3 servers as well as a Windows 7 client system. With this I don't have to have 4 different servers or PCs. I can also create virtual networks so that the virtual servers or machines can only communicate with each other.

As Dynamik said, the easiest way to really get it is to actually use it.

Here are some pics to help you see what is possible:
http://windowsitpro.com/Files/24315/Figure_02.gif (Windows XP as the Host OS running older Windows based systems)
http://www.beroux.com/articles/virtual-machines/virtual-pc-2007.jpg (A Windows XP host, running Windows Vista as a Virtual Machine)
http://i34.tinypic.com/2cmksn6.png (Windows Vista as the host running Xp as the virtual machine)

I use Sun's virtual box on my Linux laptop to run apps that I cannot get to run under Linux using WINE, for example.
Here is one of my Linux system as I was installing XP under Virtual Box.
http://docs.google.com/Doc?docid=0AaIAC_cu-e0RZGd6NWg2djVfMGc3enpzZmZr&hl=en

DerekAustin26

So its kind of like a "VLAN" - Your tricking the OS into thinking it is it's own Hardware/Server, yet its not. It is apart of the same server. your just Virtually Segmenting up the Server so you can get more efficient use out of the server as a whole.

Which this would be better rather than buying 7 different servers and having left over space on each.. Waste of space = Waste of money .

Am I understanding this correctly?

RobertKaucher

At the extreme danger of over-simplifying, yes, that's the right idea.

rsutton

One of the best features which I didn't see mentioned is the ability to take a quick snapshot of your machine, mess it up then go back a few minutes in time to your snapshot. The key word here is "quick".

Hyper-Me

rsutton wrote: »

One of the best features which I didn't see mentioned is the ability to take a quick snapshot of your machine, mess it up then go back a few minutes in time to your snapshot. The key word here is "quick".

True, however this doesnt apply in every case.

You simply can't use snapshotting in certain instances. Domain controllers, for example, can't utilize snapshotting or they break.

kalebksp

Hyper-Me wrote: »

True, however this doesnt apply in every case.

You simply can't use snapshotting in certain instances. Domain controllers, for example, can't utilize snapshotting or they break.

This is getting off topic, but what breaks when you snapshot domain controllers? I use VCB to backup all of our VMs every night (VCB creates a snapshot of each VM as part of the process) and I've never had it break anything.

EDIT: Nevermind, I don't want to hijack this thread.

SysAdmin4066

kalebksp wrote: »

This is getting off topic, but what breaks when you snapshot domain controllers? I use VCB to backup all of our VMs every night (VCB creates a snapshot of each VM as part of the process) and I've never had it break anything.

Snapshots for DCs are not supported by MS regardless of the hypervisor used because restoring a snapshot can cause the USNs on the DCs to get out of sync. On the same token, I do this all the time in lab environments and have never had a problem. I just wouldnt do something that's not supported in a production environment if you expect to get tech support help in case of problems. I believe the snapshots that VCB takes to backup VMs is different than taking a snapshot meant to restore to a point in time but I could be wrong. We currently just do system state backups.

kalebksp

SysAdmin4066 wrote: »

Snapshots for DCs are not supported by MS regardless of the hypervisor used because restoring a snapshot can cause the USNs on the DCs to get out of sync. On the same token, I do this all the time in lab environments and have never had a problem. I just wouldnt do something that's not supported in a production environment if you expect to get tech support help in case of problems. I believe the snapshots that VCB takes to backup VMs is different than taking a snapshot meant to restore to a point in time but I could be wrong. We currently just do system state backups.

Ah, good to know. My co-worker just checked and we actually don't use VCB on that VM, I'm guessing specifically for that reason.

megatran808

In lamens terms. Able to have multiple servers with just one physical server.
This saves the cost of traditional server farms.

Normally you would have a DNS/DC, DHCP, Exchange, FS, Web, etc servers on seperate boxes.

Thats 5 physical servers you need to purchase to do the job. In VMWARE you can run each server as a virtual machine on the same physical box.

Like everyone else is saying too you have the capability of doing snapshot of each server (excluding the DC) just in case something goes wrong.