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One significant new feature for the RHCSA (that's the Red Hat Certified Systems Administrator) is the introduction of the Kernel-based Virtual Machine (KVM) as Red Hat's preferred virtualization solution. Well, while it's not explicitly listed in the RHCSA objectives, KVM is the only virtual machine software available with RHEL 6.
One issue with KVM -- it's available from Red Hat only on 64-bit systems. KVM server software isn't even included in the 32-bit RHEL 6 release.
One way you may be able to get around this for purpose of your studies -- use a rebuild distribution such as Scientific Linux 6. From what I've seen, their 32-bit release includes KVM (However, I haven't tried that SL 6 feature on my own physical hardware.)
So for these five objectives
Access a virtual machine's console
Start and stop virtual machines
Configure a physical machine to host virtual guests
Install Red Hat Enterprise Linux systems as virtual guests
Configure systems to launch virtual machines at boot
You'll need to learn to use KVM. Do so, and you'll master one important topic for Linux sysadmins everywhere.
Just checked on a i386 port of RHEL 6.1, and yes, there is no "Virtualization" group of packages available (contains qemu-kvm).
However, every Intel/AMD x86 CPU today is 64-bit and almost all have enabled hardware assisted virtualization (needed for KVM) so it should not be a big problem to run x86_64 RHEL port as KVM host .
What you say is true; however, students with fewer resources may still have 32-bit systems. It bothers me that Red Hat is effectively requiring such students to upgrade. But that is life w/r/t the latest technology, and the Scientific Linux 6 32-bit loophole should work for such users.
Yup, it's relatively rare especially on older laptops. I remember checking countless BIOS menus in stores before buying a laptop in '06. I didn't keep my notes, so can't say whether all the candidates were 32- or 64-bit. But I'm pretty sure that HVM could be enabled on slightly older 32-bit desktop systems; HP comes to mind, based on user reports. Of course, user reports have been wrong before.
In any case, I did (and do) recommend the use of 64-bit systems to work with KVM on RHEL 6. (Even the lowly i3 qualifies, IIRC.)
IMO, VMs on Windows are the most difficult option. First, unless you directly install RHEL 6 (or an equivalent like CentOS/Scientific Linux) on appropriate hardware, you'll need "nested" VMs.
Until recently, the only such option that I'm aware of is VMWare ESX -- and that has a customized Linux kernel that installs directly on hardware, without any intermediate operating system.
I gather that VMWare Workstation 8 makes "nested" VMs possible. I have not tested it. The reports I've seen suggest that its sloooooooooooooooow.
In addition, when I ran VMs on Windows (years ago), I had to defragment them frequently. And defragmenting the files I used for individual systems (5GB) file (if my memory is correct) took several hours.
For the systems I specify in the book, you'll need an 80 GB file just for the VM. I have a sneaking suspicion that such a defrag would bork a day or two into the process. Even if successful, I do not know if that would create problems between the nested VMs.
stef80 is correct -- I was able to set up a working set of KVM-based VMs on my Dell laptop from '06 (with a T7200 CPU).
The key is the BIOS/UEFI -- if it's an Intel CPU, there's normally a toggle in that menu where you can enable hardware virtualization. (AMD CPUs that support hardware virtualization have no such limit.)
When successful, you'll see either a vmx or svm flag in the /proc/cpuinfo file. So if you want to be sure, get a "Live" CD or DVD, toggle the hardware virtualization setting in the BIOS/UEFI menu, and check the contents of the noted file.