Wednesday, 15 October 2014

Using Host Groups to build a Private Cloud based on System Center 2012/2012 R2



By Debra Littlejohn Shinder


Everybody is migrating to the cloud – or so it seems. But some companies just aren’t ready to put everything “out there” in a public cloud, and for them, the private or hybrid cloud deployment model makes the most sense. Building a private cloud from scratch can be a daunting task, though. Microsoft has tried to make it a little easier for customers with Windows Server 2012/2012 R2 Hyper-V and System Center 2012/2012 R2.


Definitely clouds.
Image courtesy of arztsamui / morguefile
One of the important concepts involved in creating a private cloud that’s easy to manage is that of host groups. Host groups are created in System Center 2012 R2’s Virtual Machine Manager (VMM). VMM is Microsoft’s management solution for virtualized resources, including those in a private cloud. 

A host group is a simple idea: it allows you to manage multiple servers as one entity. You can then create your private cloud based on the resources that reside in one or more of your host groups. Microsoft’s cloud computing model encompasses three resource pools that make up the fabric. These are defined as compute, network and storage pools. The three resource pools are managed by VMM. For a better understanding of this, see the post Fabric, Cloud Computing Abstraction Integrated in VMM on Yung Chou’s Hybrid Cloud blog on the TechNet web site. 

Once you have a basic understanding, you can create your private cloud. Of course, you’ll need admin privileges to do this. There are some requisites, which include the preparation of the fabric in VMM. You can find out how to do that via the TechNet article Preparing the Fabric Scenario in VMM.

Once that’s done, you can get down to the business of creating the host groups in VMM. Here’s how: In System Center 2012 or 2012 R2 VMM, open the Fabric workspace and follow these steps:


  1. In the Fabric pane, expand the Servers node.
  2. Right click All Hosts.
  3. Click Create Host Group. 
  4. Replace the default name (New host group) with the new name that you want to assign to the host group.


You can create a tiered host group structure by repeating the process after right clicking the parent node under which you want to create a new child host group. You can create a parent host group for each different physical location, for example, and then within each one you could create host groups based on hardware capabilities (that is, the top tier group in each location offers the highest level of performance and reliability, etc.). You could also group hosts based on server roles or business units, or whatever structure makes sense for your organization. Note that you can also move host groups around to different locations within the tree structure if you need to. 

After you create your host group structure, you can configure the properties of the host groups. Back in the Fabric workspace, expand Servers again and then expand All Hosts, and click the host group you want to configure. Click the Folder tab, and click Properties in the Properties group. 

Here you can configure the following host group properties: 

  • General settings (group name, location in the hierarchy, description and encryption)
  • Placement rules for customizing on which host virtual machines are deployed
  • Host reserves (the amount of CPU, memory, disk input/output, disk space and network input/output that will be allocated for the host operating system on each virtual machine, either specified for a host group or for an individual host)
  • Dynamic optimization and power optimization settings (balancing of VM loads within a host cluster and evacuation of hosts to save power)
  • Network (inheritance settings for network resources including IP address pools, load balancers, logical networks and MAC address pools)
  • Storage (allocation of storage logical units and allocation of storage pools to host groups)
  • Custom properties for VMs, VM machine templates, hosts, host clusters, host groups, service templates, service instances, computer tiers and cloud. 


For more information about building host groups, see Part 2 of Brien Posey’s 11-part article on Building a Private Cloud with System Center 2012 over on the WindowsNetworking web site or to learn more about private cloud read Private Cloud Storage Network Storage Considerations series on CloudComputingAdmin.com

Author Profile

DEBRA LITTLEJOHN SHINDER, MCSE, MVP (Security) is a technology consultant, trainer and writer who has authored a number of books on computer operating systems, networking, and security.

She is also a tech editor, developmental editor and contributor to over 20 additional books. Her articles are regularly published on TechRepublic's TechProGuild Web site and WindowSecurity.com, and has appeared in print magazines such as Windows IT Pro (formerly Windows & .NET) Magazine.