Question

Why do you think virtualization has become so popular? Discuss when and where you think virtualization would be useful, as well as cost efficient.

Answer 1

I focus primarily on Private and Public Cloud virtualization, and virtualization simplifies deployment and scalability, as well as adding huge benefits to replication, redundancy, and migration.

I love virtualization because it's quick and easy to deploy, and it separates the OS and Applications from the hardware, which means if the HOST server dies or is replaced, it's much easier to get a virtual server up and running again.

Virtualization allows for distributed cloud networking, so you can utilize Microsoft Azure or Amazon AWS for redundancy, and performance rollover. Or your own servers.   I like Hyper-V over VMWare for a variety of reasons, but primarily pricing (if you look into Virtual SAN licensing fees, etc. VMWare becomes incredibly expensive).

Virtualization is also incredibly useful for quick development and QA testing, since you can snapshot a development server, test it out, and return to the snapshot settings, which is much more difficult to do with a physical server.

Most servers utilize only a portion of CPU and Memory, so you can easily host multiple virtual servers on a single physical server, but it can increase difficulty of troubleshooting.   For example, even though memory and processing can be Silo'd so one server doesn't affect the others, DISK ACTIVITY often isn't, and one server with a problem that generates large amounts of disk activity can end up affecting the other servers - this is highlighted by the fact that you have to go to Resource Monitor in Task Manager to even really see what the disk activity is, and why a lot of system administrators believe that Virtualization can be a performance hit.

When configured and managed properly, Virtualization should actually provide a performance increase, as well as ease of deployment, inexpensive and fast backup and significant expansions in redundancy.

While I champion virtualization daily, like anything else in IT, it's about picking the right tool for the job.   If you work at a small business that only has one or two servers and a network administrator that isn't familiar with virtualization, it may be best to stick with physical servers.

But once you reach the point where you have three or more servers, it's worth considering - even if you have to enlist professional outside help, because the cost reductions a properly configured virtual environment can provide (and extended capabilities) will definitely be worthwhile.

As a final note, virtualization is key to Cloud environments as Internet bandwidth has become a non-issue in most locations, hosting your servers in a virtual environment, on the Internet, and connecting to them via VPN and RDP, etc. means that small and mid-sized companies no longer need to make outrageous investments into a data center (redundant power, cooling, bandwidth, etc.), and can offload that to a datacenter.

Following are some of the use-cases when virtualization would give optimized results.

Server Consolidation

It is not unusual to achieve 10:1 virtual to physical machine consolidation. This means that ten server applications can be run on a single machine that had required as many physical computers to provide the unique operating system and technical specification environments in order to operate. Server utilization is optimized and legacy software can maintain old OS configurations while new applications are running in VMs with updated platforms.

Although a server supporting many VMs will probably have more memory, CPUs, and other hardware it will use little or no more power and occupy the same physical space reducing utilities costs and real estate expenditures.

Testing and development

Use of a VM enables rapid deployment by isolating the application in a known and controlled environment. Unknown factors such as mixed libraries caused by numerous installs can be eliminated. Severe crashes that required hours of reinstallation now take moments by simply copying a virtual image.

Dynamic Load Balancing and Disaster Recovery

As server workloads vary, virtualization provides the ability for virtual machines that are over utilizing the resources of a server to be moved to underutilized servers. This dynamic load balancing creates efficient utilization of server resources.

Disaster recovery is a critical component for IT, as system crashes can create huge economic losses. Virtualization technology enables a virtual image on a machine to be instantly re-imaged on another server if a machine failure occurs.

Virtual Desktops

Multinational flexibility provides seamless transitions between different operating systems on a single machine reducing desktop footprint and hardware expenditure.

Parallels Desktop for Mac, a virtual machine application. Instead of Boot Camp's dual-boot approach, Parallels Desktop runs Windows XP directly on the Mac OS desktop (in what Parallels calls "near-native performance")--allowing you to run both OSs simultaneously and switch back and forth seamlessly.

Improved System Reliability and Security

Virtualization of systems helps prevent system crashes due to memory corruption caused by software like device drivers. VT-d for Directed I/O Architecture provides methods to better control system devices by defining the architecture for DMA and interrupt remapping to ensure improved isolation of I/O resources for greater reliability, security, and availability.