When I first said I wanted to talk about private cloud in the real world, I was thinking to share some deep insights. In reality, some of the insights are not so deep, but rather just part of the long list of little things you must get right to deliver on the promises of a private cloud infrastructure. The private cloud with System Center 2012 sounds great on paper (and it can be), but when you get to into the real world, there are some key elements that, if not considered and addressed in the build, make it seem so much less great. Because in the end,businesses and pay the promise of the cloud…they pay for actual results. As one Microsoft guy said, “they don’t buy the drill, they buy the hole”. In other words, “customers don’t buy the tools (System Center 2012, Hyper-V, etc.), they by the capabilities the tools will help them realize”.
Here are a few things you must get right before anything else matters.
Lesson 1: SAN copy is critical for a happy cloud (or more specifically, happy users of a private cloud)
Let’s face it,copying many gigabytes of data (in the form of a virtual machine in this case) is not fast enough. Go into this with your eyes open,understanding the requirements to deliver rapid virtual machine provisioning. Counting the time required to deploy virtual machine in minutes is anti-climactic and the end result less impressive in inverse proportion to the time required to deploy VMs. To paraphrase the TechNet article:
Before you begin, make sure that the following prerequisites are met:
- The storage array must support the new storage management features in VMM.
- The storage array must support cloning or snapshots, and have the feature enabled.
Note: Realize that this may require additional licensing from your storage vendor. (yes, some vendors license the right to clone and shapshot luns!)
- The storage pool that you want to use for rapid provisioning must be under VMM management. This involves adding the SMI-S provider for the array, discovering storage pools, classifying the storage, and setting the preferred allocation method for the storage array to either snapshot or cloning.
There’s more. See “Rapid Provisioning a Virtual Machine by Using SAN Copy Overview” at http://technet.microsoft.com/en-us/library/gg610594.aspx
Lesson 2: Configure your VMM Library share PROPERLY
Yes Virginia, there is a wrong way to configure VMM library…and this wrong way results in media being copied into your VM directories. And if you do it wrong, not only do VM copies take forever, so do ISO mounts.
as so eloquently stated by Michael Michael of Microsoft (that guy has a great name) “First, you need to follow Jose Barreto’s blog post on how to properly enable constrained delegation on the Hyper-V servers. You need to follow these steps for every Hyper-V host on which you want to create a Virtual Machine and attach a shared ISO. Additionally, these steps need to be followed for every library server that will host ISO files that are going to be linked from Virtual Machines.”
In the end, this allow you to use the “share image file instead of copying it “ option, avoiding slow and frustrating ISO mounts.
Lesson 3: With new technology comes new responsibility
Or as I like to say, “System Center won’t teach itself to you”. If your VMware admin today, you will have to learn new tools and administrative tasks. In the end, I believe your total cost of ownership (TCO) will be lower, but there will be a transition period. By looking carefully at how you do things today, it is possible to minimize the impact of this change. The good news is, Microsoft offers loads of free training to get folks familiar with System Center 2012 and related private cloud technologies. VMware certainly can’t make this claim today.
Sign-up for the Microsoft System Center 2012 Private Cloud Jumpstart at http://mctreadiness.com/MicrosoftCareerConferenceRegistration.aspx?pid=298
Lesson 4: Configure which network adapter handles Live Migration
If you allow Hyper-V and Windows to do as they will, the network you intended for Live Migration may not be the network that is used for live migration and the result will be, well….disappointing. The perceptions of continuous availability and infinite capacity cannot be realized when live migration performs like quick migration…quick migration never seemed that quick to me.
You set this value in the Failover Cluster management interface. When you choose the Live migration network for one VM, It applies the setting globally to the cluster. For Proper configuration steps And related considerations, see Windows Server 2008 R2 & Microsoft Hyper-V Server 2008 R2 – Hyper-V Live Migration Overview & Architecture
Lesson 5: Create VM templates in a few sizes, along with a few VHDs
This one isn’t too complicated, but can save a lot of time building VMs after you get started. Once you begin deploying in the cloud, you want to deploy Web servers, app servers and database servers. These roles will come with their own virtual machine requirements. Build templates before you get started is to avoid interrupting the deployment process with template creation activities. This could be as simple as small, medium and large templates. No hard and fast right answer here, but something that is driven by needs in your environment. For example, if your DBAs require specific drive letters for databases and database log files, you could create a template with this configuration built-in.
To build a stable home, you cannot build on sand. Likewise, you have to build a solid foundation of network, compute and storage for successful private cloud deployment. All of the promises of agility and economy require careful planning and execution. Next time, we’ll talk about considerations in a heterogeneous environment, or whatever related lessons I have for you from the cloud fabric.