How SCVMM Simplifies Networking with Hyper-V
Although SCVMM is covered in detail later in the book, I’ve already mentioned its use
numerous times in this chapter and I’m about to discuss it a lot more as it moves from
being an optional management technology to being the only practical way to
implement some technologies. In this section, I discuss some fundamental SCVMM
logical components and how to get up and running with them quickly, including
deploying some of the components already covered in this chapter the “SCVMM way.”
When you consider the configuration performed with Hyper-V, it really consisted of
creating a virtual switch that was tied to a physical network adapter, and the way you
named the virtual switch could indicate what it would be used for. However, if that
switch connected to an adapter that connected to a switch port that supported
different VLANs for different networks, then there was no way to convey that and
manage it effectively. Also, there was no concept of separating the network seen by the
virtual machines from that defined on the Hyper-V server. Additionally, on each
Hyper-V server, the virtual switch configuration and any extensions were manually
configured. Things get a lot more complicated when virtual switches are used for
multiple virtual network adapters on the management operating system, as you’ll see
when you look at a more converged network infrastructure later this chapter.
SCVMM introduces quite a few new concepts and constructs that initially may seem a
little overwhelming. However, they are fundamentally designed to let you model your
physical networks, your switch, and your network configurations on the Hyper-V
hosts and then model a separate abstracted set of definitions for networks available to
virtual machines. These constructs can broadly be divided into those that model
connectivity and those that model capability.
Let’s build these constructs out and then walk through a configuration for a new
deployment. One key point ideally is to perform all of your configuration through
SCVMM for your Hyper-V host. Install the Hyper-V role with no virtual switches and
do nothing else. Don’t create virtual switches, don’t create NIC teams, don’t start
creating virtual machines. The best experience is to define the configuration in
SCVMM and let SCVMM perform all of the configuration on the hosts.
One important point for networking—whether for physical hosts, for virtualization
with Hyper-V, or using SCVMM—is proper planning and design. You need to
understand your physical network topology and your requirements, and then translate
this to your virtual network infrastructure. This becomes emphasized with SCVMM
because SCVMM networking components force you to do this planning; you need to
model your network within SCVMM by using its various networking architectural
components to achieve desired results. There are three primary groups of activities
that are undertaken when networking with SCVMM:
1 . Discovery. Understand the network requirements of your datacenter and your
virtual environments. This may require asking questions of the network teams and