Busting the Myth

As more and more organizations are putting efforts in moving towards dynamic data centers, there are still many misconceptions that surround the concept. Server virtualization, which is a great enabler of moving towards a dynamic data center, has been around for ages, but still its adoption has been marred with similar fallacies, which has further slowed the overall adoption of dynamic data centers.

Most of these misconceptions are not true to a large effect but in one form or the other, perceptions have been formed which are not helping the advancement of IT infrastructure in most of the organizations. The article will discuss some of these misconceptions and try to bust the myths with right facts and figures around these, which should be considered by organizations when deciding against their progression towards a dynamic data center.

Myth #1: A Dynamic Data Center is Not a Safe Option From a Downtime Perspective

There is a common misconception that a dynamic data center does not entail adequate safety measures as compared to a physical server. As a virtualized server runs multiple applications from the same compute power unlike a physical server, the notion is that maintenance and other downtime activities would cause non-availability of applications, and operations would be impacted more in a dynamic data center.

 

Fact: Virtualization natively has capabilities to provide more redundancy to applications as it offers functionalities like high availability and live migration, which mitigates all risk elements in case of any malfunction. The applications that are running in a virtualized environment are much safer because there are various mechanisms to safeguard an application in case of any planned or unplanned downtime.

Myth #2: Security and Virtualization Do Not Go Hand-in-hand

It is wrongly considered that a dynamic data center is more prone to security threats as all applications and operating systems reside and share compute in the same environment. With many virtual machines being run from the same compute, organizations worry that if one application or virtual machine gets compromised, all the other applications running on the virtualized server will have equal risk of being affected.

Fact: A dynamic data center comprises of a virtual environment where each and every application is working in its own isolated container with individual CPU and memory instructions. If at all there is a compromise of security in one virtual machine, it does not affect other virtual machines. This makes applications running on a virtualized environment as secure as those running in a physical environment.

Myth #3: Application Performance Suffers

Organizations believe that applications do not deliver optimal performance in a dynamic data center. This stems from the notion that the total hardware capacity which was traditionally used for one application will now be stretched across different applications. Especially in the case of mission critical workloads such as database, exchange, CRM, ERPs organizations are usually skeptical to migrate to a virtualized or dynamic data center due to supposed' performance concerns.

Fact: The very premise on which virtualization was based is the fact that applications running on a native physical hardware were suboptimally utilizing its compute capacity. The applications' performance is not hindered because the total available compute in hardware is in surplus and all applications share this excess compute. There are Citrix white papers available where we have compared equals of different configurations running on physical environment vs a virtual environment and more or less the IOPS (Input/Output Operations Per Second) has been found to be similar across physical and virtual environments with minimal virtualization overhead.

This can be corroborated by a Citrix study to determine the transaction processing performance of SQL server 2008 using Citrix XenServer 5.0 virtual machine SQL servers as compared to physical SQL servers. There were 3 test groups considered for this study and following are details of one of them

Test group: Medium8 Core/28 GB physical or virtual host server

Single instance physical server vs single VM server

Two instance physical server vs 2 VM server

Four instance physical server vs 4 VM server

 

 

The Results

XenServer virtualized a single VM workload with only 7.5% virtualization overhead. Due to an inability to support more than 4 vCPUs, Vendor X was unable to compete with XenServer in this single instance vs single VM, 8 core/28 GB test.

XenServer outperformed the physical server in the 2 and 4 instance tests, 6.7% and 27.8% better, respectively

XenServer outperformed Vendor X in the 2 and 4 instance tests, 15.7% and 15.5% better, respectively

One, 2, and 4 instances of SQL server on virtual servers vs the same number on one physical server

Myth #4: One will have to Go Through the Rigmarole of Reconfiguring All Existing Applications to Make it Virtualization Ready

Organizations believe that every application needs to be reconfigured and reinstalled while migrating from a physical data center to a virtualized data center. Since physical data center involves the process of installing and configuration of applications, there is a general misapprehension that a complete overhaul of almost 6-8 months is required to implement this change.

Fact: There are many virtualization software providers that enable the customer to function in the production environment and migrate applications to a virtualized set up without having to redo, reinstall or reconfigure any of these applications. For instance, an exchange with 500 mailboxes, configured from routing and mail delivery perspective, can be migrated overnight without any re-installation or reconfiguration of exchange, provided the base infrastructure is ready. The end users will be least aware or impacted whether they are accessing data through a physical exchange mailbox or a virtual exchange mailbox. Such migrations are supported by a virtualization converter software, that facilitates the conversion of a physical server (or PC) into a virtual machine.

 

Myth #5: ISVs Don't Support Virtualized Applications

A preconceived notion on this subject is around the lack of ISV support for applications running in a virtualized environment given the context that it is being run in a completely different environment than before.

Fact: The virtualization industry has matured over the years and most of the ISVs around the world have published statements on their website, acknowledging their support for applications in a physical or a virtualized environment and there is no difference in treatment when it comes to troubleshooting a problem across either platforms. Hence customers can be rest assured while moving towards a dynamic/virtualized data center to run their applications.

Myth #6: Won't Be Able to Manage Applications Due to Excessive Flexibility

While it is a known fact that a virtualized data center is very flexible in nature, it is this very quality that can be misconstrued by CIOs. In a physical environment, the application is tied to a physical host and therefore, is always limited within that physical hardware and infrastructure. However in a dynamic data center, there are no boundaries as to where an OS or an application may reside. It may reside on one physical hardware on day 1 and on day 5, it may be on physical hardware number 3 in the data center. The point of contention is that this would make it difficult to track, manage, and have complete control over the movement of these applications.

 

Fact: Flexibility is the biggest advantage of migrating to a dynamic data center from a static one. As compared to a traditional data center where delivering a new application would take almost 2-3 weeks, one can make this possible through just 2-3 hours by provisioning the requisite VM and getting the application up and running. The key to success is to hand over the controls to specific set of people rather than everyone in the IT team having the flexibility to move around applications and activate new VMS.

In a nutshell, the dynamic data center is inherently much more manageable, and its flexibility and agility can be well-managed through the management console that comes with the virtualization software which makes it a centralized and granular management experience.

Myth #7: I Will Have to Hire Skilled Resources for the Virtualized Environment

Right from the history of managing physical servers and switches, the natural presumption is that moving towards a virtualized data center will require the need to hire different kind of skilled resources. Companies assume that their employees will also have to go through a huge learning curve to operate in virtual environment.

Fact: #1, it is important to understand that professionals with virtualization skillsets do not come from a pure play virtualization background. Resources that have matured into the virtualization arena are the ones who have been managing the data center for a long time. These are professionals with strong server, storage, and networking fundamentals and have graduated towards the virtualization skillset perspective. To this effect, there are no specialized resources needed to be hired to manage the new virtualized environment. During the transition phase, there might be a need for skilled professionals in this area which can be provided by the organizations that are providing this virtualization transformation.

 

But, once the transformation has been achieved, the existing set of skilled resources that are familiar with server and storage and networking technologies can very easily enhance their skillsets and continue to manage the transformation from a static to dynamic data center and going forward, the transition to the cloud side of the environment as well.

Myth #8: Server Virtualization is Not the Same as Dynamic Data Center

While server virtualization is one of the key technologies enabling a dynamic data center, there is a popular belief that adopting server virtualization equates to creating a dynamic data center.

Fact: Server virtualization is one of the many elements contributing towards organization's progress in creating a dynamic data center. While virtualizing servers will certainly enable dynamism in a data center, there are other aspects of data center like storage virtualization, network virtualization, and monitoring and maintenance of applications which also need to work in tandem. The way you use storage and network along with your virtualized environment and the way you monitor and back up this virtualized environment are also important in moving towards an optimally dynamic data center. And, all these factors should be looked in a holistic manner while moving from a static data center to a virtualized and a dynamic data center.