Why do we need virtualization?

Apart from saving time, money and energy, it:

• Helps you to manage your resources efficiently
• Provides a secure remote access and thus increases productivity
• Helps against data loss prevention

What makes virtualization possible is a software known as a hypervisor or a virtualization manager. The VM sits between the hardware and operating system and basically allocates the amount of access that applications and operating systems have with the processor and other hardware resources.

Choosing the right technology for virtualization is essential. The two main choices when it comes to virtualization are Virtuozzo and KVM. Depending on your needs, either of these could suit your requirements. Here are the pros and cons of both Virtuozzo and KVM.

Virtuozzo at a glance

With Virtuozzo, the resources of your server are efficiently split. However, it’s not free and it’s not an open source program (unlike OpenVZ). It doesn’t use the normal hardware abstraction layer construction. Instead, Virtuozzo comes with a proprietary Kernel Service Abstraction Layer (KSAL) that manages access to the kernel and basically prevents any single VPS from bringing the entire physical server down. It approaches virtualization by running a single OS kernel as its core. The core is then exported to various partitions on the host and each partition becomes an independent entity better known as a virtual private server (VPS).

KVM at a glance

Kernel-based Virtual Machine (KVM) is a virtualization infrastructure for the Linux kernel that turns it into a hypervisor. It only works with the Linux OS but does support Windows, BSD and Solaris as guests.

Virtuozzo is container-based while KVM is a hardware-based virtualization. KVM runs on x86 and x86-64 systems with support for virtualization extensions. It’s an open source choice and consists of a loadable kernel module. This module provides the virtualization infrastructure core and it also provides a processor specific module.

Pros and Cons of Using Virtuozzo

The Pros

• Independent Platform – You can use Virtuozzo with Windows or Linux without any hassle
• Web-based GUI panel – The Virtuozzo Power Panel is a GUI based web powered panel, which enables you to handle servers on their own over the web
• Easy Restoration – Restoring is easy and comes with full root access. You’re also able to restore an individual file or the entire VPS

The Cons

• RAM is shared – If the server doesn’t have enough RAM, Virtuozzo struggles and usually will fail since the system depends on virtual RAM. Ultimately, it will kill processes when it runs out of RAM
• Lack of device support – In some cases, Virtuozzo won’t allow custom devices. For example, VPNs
• Resource sharing isn’t great – The resource sharing of Virtuozzo isn’t that great. If one user is using resources heavily, it can slow things down.

Pros and Cons of Using KVM

I’m sure you already know that KVM is one of the top open source choices for virtualization. Then again.

Pros of using KVM

• Excellent Security – Since the base of KVM is made up of Linux, it uses the SE Linux advanced security system. This helps to ensure security of the virtual machines meets a very high level. KVM has also received awards for meeting the security standards of the government.
• Available for Anybody to Use – The open environment of KVM means anybody can use it and customize the system to fit specific requirements.

Cons of Using KVM

• Complex Setup – One of the main disadvantages of using KVM is the complex setup process. It’s actually more complex than other systems
• Limited Processors – Keep in mind that the system doesn’t work with all processors
• May Require Built-in CPU Virtualization Support – In some cases, KVM may require built-in CPU virtualization support to ensure the best possible performance.

Overall, using KVM can be beneficial, it could outweigh the disadvantages for some users. But then again, the use case depends on the user. Here are a few highlights that you can have a look at

Virtuozzo

• Can only host Linux operating systems
• Most Virtuozzo hosts are oversold
• More affordable, provides users with speed and scalability
• Easier to set up

KVM

• Can host Linux, Windows and custom OS options
• Is better isolated even though it can be oversold
• Offers private virtualized hardware and is more customizable
• Requires more networking knowledge

If you’re looking for full control over your server, KVM is your go-to. On the other hand, Virtuozzo is a great choice if you don’t have any special requirements and is more affordable than KVM. Then again, it’s vital to crosscheck and look at the benefits and how they apply to your situation. If your choice of virtualization boils down to the two of these, make sure you weigh your options before making a decision. What do you prefer using for your customers? Do let us know any other parameters of comparison that you found useful to evaluate.