KVM (kernel-based virtual machine) is a Linux virtualization tool that makes use of hardware-assisted virtualization (also called native virtualization) using processor technology such as Intel VT-x and AMD-V. Red Hat’s Virtual Machine Manager now has support for KVM, making it easy to setup a virtual machine with a free graphical interface. It is also available for Fedora, Gentoo, FreeBSD, Ubuntu, and many other operating systems.

Installation

Installation will vary according to the operating system, but we will look at the Ubuntu installation to get an idea of what it entails. Since KVM requires hardware virtualization capabilities, you need to make sure your computer’s processor supports it.

Open a terminal and type this command:

egrep -c '(vmx|svm)' /proc/cpuinfo

The output will either be a “0″ or a “1″. A “0″ unfortunately means that you do not have hardware virtualization. If you get a “1″ and have virtualization enabled in your BIOS, you are good to go. Without hardware virtualization, you cannot use KVM extensions. You can still run virtual machines, but they will be painfully slow, as I discovered on my laptop with an old Intel T4200 processor.

If you want to double check the results, you can also run this command:

kvm-ok

If all goes well, it will return:

INFO: Your CPU supports KVM extensions
INFO: /dev/kvm exists
KVM acceleration can be used

Ubuntu has some meta-packages you can install to get the virtualization tools you need. With one command, you can install most of them:

sudo apt-get install ubuntu-virt

If you want to install each package manually, see the Ubuntu documentation. After the installation, you should have qemu-kvm and virt-manager (the graphical frontend) installed.

Post-Installation

After installation, you need to make sure KVM is configured and given the necessary permissions. Type this command:

groups

Among your user groups, you should see “kvm” and “libvirtd”. If either or both are missing, you can run these commands to add your local user to the groups:

sudo adduser `id -un` kvm

sudo adduser `id -un` libvirtd

The last post-installation step you need to take is to logout and log back in. If you do not, you will get a qemu error like this: “libvir: Remote error : Permission denied”

Create a Virtual Machine

Once you are logged back in, you can start Virtual Machine Manager. It should be in your applications menu. Alternatively, press Alt+F2 and type virt-manager.

On the first run, there will only be one available button to click labeled “Create a new virtual machine”. Click it and go through the creation process.

1. Name the virtual machine. It can be pretty much anything. It is only an identifier for you to remember what it is.
2. Choose the installation method. In this example, I am going to use a CentOS 6 LiveCD ISO. That requires the first option “Local install media”. After choosing, click “Forward”.



3. Select the OS type and version. In my example, I chose “Linux” and “Red Hat Enterprise Linux 6″.
4. Select the amount of RAM you want to allocate and the number of CPUs to use.
5. Set your virtual disk size. This largely depends on the OS you are using and the amount of space you think you will need.



6. Set your network options. In most cases, the right option is already selected.
7. Click Finish

Virtual Machine Manager should immediately start booting your virtual machine. If you booted from an ISO, you can then install the OS as you normally would or even run it from the LiveCD. If you want to see real-time information about your virtual hardware, click the “show hardware virtualization details” button. You do not have to keep the virtualization window open to keep running your virtual machine. This is useful if you only intend to connect to it remotely and use it as a server.

For more information about Virtual Machine Manager, visit the online wiki. For more information about KVM, see the online documentation.

Portable apps can be very handy if you only need a few applications. Portable Virtualbox enables you to bring along the whole OS in a thumb drive, but it can be slow and often take up a big chunk of your USB storage space. What if you can have the best of both world – a lightweight and portable OS that contains all the applications you need?

Prayaya V3 creates a portable Windows operating system on your removable storage device such as USB drive, iPod, external hard disk etc and allows you to install your own applications (and games), customize your own settings and even manage your own bookmarks. You can then bring the storage device around in your pocket and use it on any Windows computer.

Note: We have free giveaway for this great software. Read on for more detail.

Unlike portable virtualbox, Prayaya does not need a full OS image. What it does is to hook the kernel of the Windows PC and redirect the file operations. It only needs to store the important kernel files in the removable drive to work in any Windows PC. This also explains why it doesn’t take up a lot of space in your USB drive. In fact, the installation only requires a mere 15Mb of free space.

Usage

Firstly, download the installer in your Windows PC (it works with Windows XP, Vista and Windows 7 32-bit). The trial version is fully functional for 30 days. Plug in your removable device and run the Prayaya installer.

When prompted, select the removable drive as the installation destination.

After the installation, open your Windows Explorer and navigate to the removable drive. Double click on “StartV3.exe” to run Prayaya.

You will be asked to login to your Prayaya account. If you do not have a Prayaya account, click on the “register account” link to create a new account. This will be your main user account, so don’t forget your username and password.

Next, you will see the Prayaya virtual desktop. It is a stripped down version of the host Windows OS (If the host OS is WIndows XP, the virtual desktop will also follow the XP layout).

The basic virtual desktop comes with system applications like Windows Explorer, calculator, notepad, Paint, Games etc. Since my host Windows is running IE9, the virtual desktop also have a copy of IE9 browser.

There is a toolbar at the top of the virtual desktop. This will also be your main command center. The center icon allows you to switch between the host OS and the virtual desktop (or use the shortcut key “Alt + q”).

Applications

The installation of third party applications is the same as in any Windows platform. Simply download the installer and run it within the virtual desktop. Prayaya also comes with a software list with hyperlink for you to download the installer.

Screenshot of GIMP running in the virtual desktop:

Virtual desktop or small windows mode

In the Settings, you can configure Prayaya to start in a virtual desktop or small windows mode.

In the small windows mode, you will only see a small window (akin to your Start menu) with links to your applications. This will allow you to work on the host computer and have access to your virtualized apps. For those who have used PortableApps, you will find this interface familiar.

Things to improve

At the moment, there is no ways to save the sate (aka hibernation mode) of the virtual desktop, just like in Virtualbox. Everytime you start Prayaya, you have to restart the apps individually, which can take up a lot of time, depending on the host machine speed. Hopefully the developer can add in the “save state” feature in the next version.

Free Giveaway

The developer of Prayaya V3 has gladly sponsored us 5 license keys to be given away. Here’s how you can participate:

Step 1

Be our Facebook fan or follow us in Twitter:

STEP 2

Fill up the form below. This is to make sure that we can contact you when you win the license. We promise that we won’t spam you.

Update: the giveaway contest is now closed.

STEP 3
Share this post either in Facebook or Twitter, and leave a comment.

This giveaway begins now and ends Thursday, 7th October at 2359hrs Eastern Time. The winners will be selected at random and announced via email.

Update: the giveaway contest is now closed.

Share and enjoy!

Cameyo is a Windows only software that virtualize your applications into a single exe file. With this virtualize application, you can bring it around and use it in any computers, without installation.

Usage

Download and install Cameyo

Run Cameyo. Click “Capture installation”.

It will first take a snapshot before the installation.

When the Proceed with installation message appear, proceed with your application installation.

In this example, we will install the Opera browser in our Windows system.

When the installation is completed, simply click the “Install done” button.

Cameyo would then proceed to take a post installation snapshot to determine the files/folders that have changed. This could take some time. It is best to leave your system alone during this process

Once it is done with the snapshot, it will prompt you to enter the identification detail.

Lastly, it will package the executable into a virtual file.

You should now see a folder in your desktop. Inside the folder should contain the executable file of the application that you have just installed.

Now, you can copy this folder to your thumb drive, bring it around with you and access to your applications wherever you are.

Conclusion

Personally, I have not test every single application in my system, so there is no way to know if Cameyo works for all. I have tested Opera, Safari browser and Filezilla. The post-installation snapshot of Safari took far too long, so I cancelled it before it was completed. As for Opera and Filezilla, they work fine.

Test it out and let us know which applications work and which one don’t.

For example: If you are using Windows xp, you can install popular virtualization software like Windows virtual PC, Vmware workstation to create a virtual machine within your current operating system. Now in that virtual machine, you can install any operating system e.g Windows xp, vista. You can run these operating systems in a new explorer window within Windows xp.

The problem with virtual machines is that you have to install an operating system from scratch. This includes loading the operating system from cd or dvd, installing all the drivers and system software etc. This can be very time consuming and is not a quick job.

How to Convert your Existing Operating System into a Virtual Machine

Microsoft has a free application named Disk2vhd, which can create a virtual machine of your existing operating system. The utility is a portable application and does not require any installation. You can run the virtual machine on any computer you want.

Following are the steps involved to create the virtual machine of your existing Windows operating system:

1. Download the Zip file (751 Kb) and extract it. After that, just run the Disktovhd. exe.

2. The application will show you the available drives in your computer.

3. Select the drive which you want to migrate as a virtual machine. In this case, i would want to create a virtual machine for my Vista installation, hence i have selected the D drive.

4. Specify the path where you want to save the virtual hard drive (vhd) file. The file would be of large size and almost equal to the size of the operating system drive.

5. Hit the Create button. It would take some time to create the vhd file (mine took 25 minutes).

The software will clone a virtual hard disk of the drive selected and save it in specified location. After the vhd file has been created, you can use any virtualization software to mount the virtual hard disk and run the operating system as a virtual machine.

For example: I mounted the virtual hard disk on Microsoft Virtual PC and ran Windows Vista as a virtual machine under Windows xp. The software can convert the chosen hard drive into a vhd file, even if it is under use.

How can the Virtual machine be useful

Using a virtual machine has many advantages, especially when you are tech savy. Consider you are working in Windows xp and need to test a small Windows application compatible with Windows vista only. In that case you have to boot your system and start Windows vista again. A virtual hard disk of vista will come in handy here as you can start testing the vista compatible application by starting a virtual machine in xp.

Another situation where virtual machine can be a real time saver is when you are using multiple computers. Suppose you want to work in your friends computer with all your installed software and applications. In that case, just create a virtual hard drive of your operating system and carry the vhd file in a usb stick. When you are using the friend’s computer, just mount the virtual hard disk and use all your installed software.

Disktovhd can be used to create virtual hard drives of Windows xp, Windows vista, Windows server 2003. If you are using Ubuntu, check out how to create an Ubuntu virtual machine.

Today, we’re going to be using chroot to treat certain parts of your Linux filesystem as (almost) completely isolated systems. This can let you do all kinds of interesting things, like run a full Gentoo system from inside your Ubuntu system with little to no performance loss.

How it works

Before we get started, it would be a good idea to go over exactly what we’re doing and how it all works. When you start up your Linux computer, you go through a series of steps to boot up. GRUB, your bootloader, loads the kernel that’s specified in GRUB’s config file, attaches it to your root partition, and runs the init scripts stored there. From then on, your system is running from within that root partition.

We’re going to be using a host Linux system (I’ll be doing it from Debian but the steps should be pretty much identical regardless of distribution) that goes through that normal boot process, but then treating a certain portion of your filesystem (like /mnt/guest) as its own isolated installation. That guest system won’t go through the boot process, won’t load a kernel, and won’t run init scripts. You’ll just tell your host “connect to this directory as if it’s the new root partition”. The diagram below should help demonstrate what I mean.

This is approximately how the files will be laid out on your system, just sitting there as normal files on a normal partition, treated the same as any other files until we use “chroot” to make them into something special.

But once we use chroot (CHange ROOT) and point it to /mnt/guest (or wherever we put the files in the next step), that directory is now its own root filesystem. It becomes completely oblivious to the host system. All programs and commands run from within that new root are run based on the software inside that new branch.

For example, if you’re chrooted into /mnt/guest and type “ls”, it’s reading the “ls” command from inside that chrooted environment, completely unaware of the “ls” command on the host system. If you type “firefox”, it runs the Firefox from inside the new root, whether or not you’ve got Firefox installed on the host.

Getting and Using the Guest Distro

To make this work, you just need the base filesystem of a Linux distro, whatever distro that may be. Debian has a great tool for just this purpose called debbootstrap which downloads the base files and places them wherever you like. To keep things interesting, and to demonstrate what chroot can do, we’re going to use a Gentoo filesystem for our guest. To keep things simple and direct, I’m going to include the download of the tarball as one of the steps we’ll do at the command line.

These steps are going to download all the base files for a Gentoo system, extract them into our target directory (I’ll be using /mnt/guest but you can use anything you like) and then chroot into that directory so it’s treated as the new root (/) directory. You may need root (sudo) permissions for some of the following commands.

mkdir /mnt/guest
cd /mnt/guest
wget http://distfiles.gentoo.org/releases/x86/2008.0/stages/stage3-x86-2008.0.tar.bz2
tar -jxvf stage3-x86-2008.0.tar.bz2
chroot /mnt/guest

Those commands take the following steps, in order of line number:

1. Create the space for our guest system to live
2. Move into that space
3. Download the Gentoo system files
4. Extract them
5. Treat this new space as the root (/) directory

The following screenshot should help demonstrate that once we’ve used chroot to connect our new directory as root, it is now isolated from the previous branches in the filesystem tree.

To explain the screenshot, we’re starting at a normal command prompt on the host system. I’m using pwd to display my current directory, where all Gentoo’s files are sitting as plain old files with no special meaning. I then use chroot to treat this directory as the new root, and you can now see visually that my prompt has changed because the command line is now pulling all its info (including how to draw the prompt) from within Gentoo’s root environment. ALL commands and actions I take while chrooted in depend on those commands existing within that new file tree. When I type pwd again, it no longer says /mnt/guest, because as far as that shell knows, nothing exists other than what it sees inside that tree.

Things to Keep In Mind

As I hinted above, this isn’t 100% isolated from the host system. The chrooted environment was never “booted up”, so it never loaded its own kernel, and never ran its own init scripts. In our example, we’ve got Gentoo running on the kernel that the host (in my case Debian) booted up with.

This method is certainly not a replacement for virtualization, and can not do everything VM software can do. The guest system never actually “boots” or runs init scripts, and it’s possible your guest OS may require some features your host kernel does not offer.

What for?

In the times I’ve mentioned this technique to people in the past, they’ve often said something along the lines of “That’s cool, but what would you use it for?”. Personally I’ve found several uses for chroot:

• Test developing software in a pristine environment
• Run software meant for another distribution
• Run software that requires an older or newer version of your current distro
• Access a Linux installation on a different partition without having to reboot
• Boot a Live CD and use chroot to repair your installation or GRUB
• Access a drive where you’ve forgotten the user/pass
• Run a 32-bit app in a 64-bit environment

And I’m sure there are plenty more that I’ve never though of. Have you ever used chroot to run multiple distros? How about to repair a Linux system from a Live CD? Let us know in the comments.

To make sure there’s no confusion, I’m NOT talking about multiple monitors. The idea behind this article is that we’ll have multiple desktop environments running on the same computer at the same time, and we’ll be using keyboard shortcuts to switch between them.

For anyone who’s not sure what I mean when I talk about “X”, that’s the shorthand name for the X Window System. Most modern distributions use X.org to handle all their graphical needs. Basically, any time you’re seeing graphics (not just plain text), you’re probably looking at X. It manages the display for Linux and controls what’s on your screen and how it’s handled.

Virtual terminals

X keeps track of things by screens or displays. Right now, if you’re reading this article in Linux, you’re probably on the default screen number 0. You can access the different screens with key combinations. To try it out right now, try hitting Alt+Ctrl+F1. That’ll take you to your first console screen. To get back to the graphical screen, hit Alt+Ctrl+F7. Many people use this as a way to drop to a fullscreen terminal without having to close X.

At this point, you may be thinking “Why F1 and F7?”. Well I’m glad you asked, even though you didn’t really ask. When holding Alt+Ctrl, keys F1 through F6 are your console screens. They’re commonly called virtual terminals. Each one has a separate instance of the console running on it, and you can flip back and forth between them using Alt+Ctrl+(F1 through F6).

Once you get past F6, you’re in X’s territory. Much like the virtual terminals, each screen starting with F7 is a separate instance of X, which can have its own programs running, independent of the other screens. So what we’re going to do now is set things up to launch your other desktop environment in the next screen over.

Setting up the second screen

For starters, we’ll want to install whatever window manager or desktop environment you’d like to have running on your second display. In a move that will surprise no one, I’ll recommend Window Maker. For the remainder of this article, I’ll assume that you’re running Ubuntu in the default configuration and that the desktop environment you want to use is Window Maker.

Once you’ve installed Window Maker (or whatever other desktop you’d prefer) the first thing we need to do is open/create the file .xinitrc in your home. When X is launched from the command line, it reads this file to decide what needs to be run when X starts. So open or create the file .xinitrc in your home directory, and add the line:

exec wmaker

and save.

Running the second desktop

Now we’re at the main event. Open your command prompt and enter:

startx -- :1

That will tell X to start and to use display number 1 (instead of the default of 0 which you’re probably using as your main desktop). If all went well, you’ll find yourself looking at the default (and kinda ugly) base Window Maker desktop. To switch back to your main desktop, use Alt+Ctrl+F7. Back to Window Maker is Alt+Ctrl+F8. If things didn’t go so well, see the Troubleshooting section below.

Alt + Ctrl + F7 = Gnome desktop

Alt + Ctrl + F8 = Window Maker desktop

Troubleshooting

X: user not authorized to run the X server, aborting.
This one is a config issue, and one that’s easily remedied. Open the following file as root:

sudo gedit /etc/X11/Xwrapper.config

Change

allowed_users=console

to

allowed_users=anybody

I can’t claim to know enough about X’s programming to be able to make any educated statements about potential security problems this may or may not present, but it fixes the problem.

X: client 1 rejected from local host
Another simple fix, just delete any files in your home directory that has a filename starting with .Xauthority

You can repeat this process to add any other desktop environments you may happen to want, just change the 1 in

startx -- :1

to 2, 3, etc. There are plenty of function keys left!

Make Tech Easier has extensively covered VirtualBox a couple of times earlier and we are great fans of this cross platform, open source application.

One thing which VirtualBox was missing till some time back was support for 3D acceleration for guest operating systems. What this means is that the graphics driver used inside the guest virtual machines was only capable of simple 2D graphics and thus interfaces like Compiz on Linux and Aero on Vista were not useable.

There was basic 3D support for Windows guests in Virtualbox 2.1 but users using Virtualbox to run Linux guests were mostly confined to the 2D graphics driver. That has changed with the release of VirtualBox 2.2 recently and VirtualBox now supports 3D acceleration. The 3D acceleration support built in VirtualBox uses your native machine’s graphics hardware to provide this capability, so if your native graphics driver doesn’t have 3D capability, VirtualBox cannot make use of it.

The support for 3D acceleration is not enabled by default and with this tuturial we aim to help you guys set up a new virtual machine with 3D accelerated graphics support.

First create a new Machine the usual way, and install a guest operating system in it. We used Ubuntu for our testing.

Now, you need to edit the settings of your newly created virtual machine. To edit the settings for any virtual machine, the virtual machine has to be shut down. So, first shutdown whatever operating system you have running inside the virtual machine.

Now, while the virtual machine is highlighted, click on the Settings button to open up the settings window.

In the general settings pane, check the check box titled, “Enable 3D acceleration”.

That’s it. The virtual machine has been enabled for 3D accelerated graphics now. But, to actually start using 3D effects inside your guest operating system, you need to be using the special VirtualBox graphics driver, which is distributed with the “Guest Additions”.

To Install the VirtualBox “Guest Additions” drivers in your guest operating system, while the guest is running, click on the Devices menu and select the “Install Guest Additions” option.

Now, follow the instructions to install the drivers in the guest operating system.

Now, you can enable Aero or Compiz effects in the guest operating system and make full use of the graphical capabilities of your machine’s graphics card.

Summary of steps involved and software needed:

1. Download QEMU manager and Install on windows platform

2. Create Linux Virtual Machine and Install Ubuntu on virtual hard disk

3. Run the Virtual hard disk from windows platform.

4. QEMU manager and Ubuntu ISO image are needed as software requirements.

Steps to Install QEMU manager and Create Virtual Machine

1. Download QEMU manager and install on Windows platform. Screen shot of QEMU manager with virtual machines are shown below.

Click to enlarge

2. Create a new Ubuntu Virtual machine by clicking Options -> Create New Virtual Machine or by clicking the ‘+’ sign.

3. After creating the virtual machine, configure the virtual machine by setting the memory size required and choose the location of the ISO image which is to be installed into the virtual machine. Set the boot option as shown below

4. Once boot parameters are configured properly, click the ‘Run‘ virtual machine icon to launch the virtual machine.

5. QEMU will run the emulator and boot Ubuntu from the ISO image. Follow the onscreen instructions to install Ubuntu

6. Proceed with the standard Ubuntu installation procedure by choosing the keyboard map, region settings as per your preference.

7. Select Guided partition option and click Forward to proceed further

8. Enter your login option and proceed to install Ubuntu to the virtual hard disk.

9. Once the installation is completed, you will be able to run the virtual machine from the virtual hardisk. Make sure you select the correct boot parameters .

Note : The keyboard shortcut to switch focus and return back to Windows is CTRL +ALT .

Some of the advantages of using QEMU:

1. Easy to use and run with minimal system memory, say 512MB RAM.

2. There are option that allows you to create VMware virtual disk.

3. Plenty of options provided for optimal virtualization.

As for the disadvantage, there is no option for you to save the state of the Virtual machine  or to pause the virtual machine and shut the system.

Have you tried QEMU before? How do you find it?