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How does virtualization work?

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Software called hypervisors separate the physical resources from the virtual environments—the things that need those resources. Hypervisors can sit on top of an operating system (like on a laptop) or be installed directly onto hardware (like a server), which is how most enterprises virtualize. Hypervisors take your physical resources and divide them up so that virtual environments can use them. Resources are partitioned as needed from the physical environment to the many virtual environments. Users interact with and run computations within the virtual environment (typically called a guest machine or virtual machine). The virtual machine functions as a single data file. And like any digital file, it can be moved from one computer to another, opened in either one, and be expected to work the same. Resources are partitioned as needed from the physical environment to the many virtual environments. Users interact with and run computations within the virtual environment (t

What is virtualization?

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virtualization   is technology that lets you create useful IT services using resources that are traditionally bound to hardware. It allows you to use a physical machine’s full capacity by distributing its capabilities among many users or environments. In more practical terms , imagine you have 3 physical servers with individual dedicated purposes. One is a mail server, another is a web server, and the last one runs internal legacy applications. Each server is being used at about 30% capacity—just a fraction of their running potential. But since the legacy apps remain important to your internal operations, you have to keep them and the third server that hosts them, right? Traditionally, yes. It was often easier and more reliable to run individual tasks on individual servers: 1 server, 1 operating system, 1 task. It wasn’t easy to give 1 server multiple brains. But with virtualization, you can split the mail server into 2 unique ones that can handle independent tasks so

STEP-BY-STEP: CONFIGURING A 2-NODE MULTI-SITE CLUSTER ON WINDOWS SERVER 2008 R2 – PART 2

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In Part 1 of this series, I showed you how to prepare your multi-site cluster, including setting up the Node and File Share Majority Quorum. In Part 2, we saw a  video example of how to integrate SteelEye DataKeeper, one of the available cluster replication solutions, with failover clustering to configure a multi-site Hyper-V failover cluster. In Part 3, we will examine how Microsoft SQL Server 2008 can be configured in a multi-site cluster with Windows Server 2008 Failover Clustering and  SteelEye DataKeeper  Cluster Edition. First, why would you want to deploy a multi-site SQL server cluster? SQL Server comes with a variety of high availability options, including log shipping, replication (transactional, merge, snapshot), database mirroring and failover clusters. There is a great article that talks about the High Availability options in SQL Server 2008, so I won’t re-invent the wheel here. If you want to learn more about all of the options, have a look at this article by Ross Mis