with some kind of external storage enclosure that can be connected to both servers, or
with Windows Server 2016, another option would be to deploy four servers with
internal storage and leverage Storage Spaces Direct for clustered storage. This enables
virtual machines to be moved between the servers, allowing high availability, which
brings us to the next benefit of virtualization.
Physically deployed services that require high availability must have some native
high-availability technology. With virtualization, it’s still preferred to leverage the
service’s native high-availability capabilities, but virtualization adds options and can
provide solutions where no native capability exists in the virtualized service.
Virtualization can enable virtual machines to move between physical hosts with no
downtime using Live Migration, and it can even provide disaster-recovery capabilities
using technologies such as Hyper-V Replica. Virtualization also allows simpler backup
and recovery processes by allowing backups to be taken of the entire virtual machine.
Consider the process of deploying a new service on a physical server. That server
configuration has to be specified, ordered, delivered, and installed in the datacenter.
Then the OS has to be installed and the actual service configured. That entire process
may take a long time, which lengthens the time it takes to provision new services.
Those delays may affect an organization’s ability to respond to changes in the market
and react to customer requirements. In a virtual environment, the provisioning of a
new service consists of the creation of a new virtual machine for that service; with the
right automation processes in place, that could take minutes from start to finish,
instead of weeks. Because resources are pooled together in a virtual infrastructure, it
is common always to run with sufficient spare capacity available to allow for new
services to be provisioned as needed, and as the amount of free resources drops below
a certain threshold, new hardware is purchased and added to the virtual infrastructure
ready for additional services. Additionally, because the deployment of a new virtual
machine does not require any physical infrastructure changes, the whole process can
be completely automated, which helps in the speed of provisioning. By removing
many manual steps, the chances of human error are removed, and with a high level of
consistency between deployed environments comes a simplified supportability
process.
Finally, I want to touch on using public cloud services such as Microsoft Azure
Infrastructure as a Service (IaaS), which allows virtual machines to be hosted on
servers accessed over the Internet. When using virtualization on premises in your
datacenter, and in this case specifically Hyper-V, you have full compatibility between
on and off premises, making it easy to move services.
There are other benefits that are specific to virtualization, such as simplified
networking infrastructure using network virtualization, greater quality-of-service
(QoS) controls, metering, and more. However, the benefits previously mentioned are
generally considered the biggest wins of virtualization. To summarize, here are the key
benefits of virtualization:
Abstraction from the underlying hardware, allowing full mobility of virtual