Ten steps to uncover the mysteries of virtualization technology

The benefits of server virtualization now are significant, and it is a natural choice to implement the technology. First, server virtualization makes more use of computing resources than physical servers, because you can run many different virtual servers on a single physical host. In fact, the number of common server instances that a single current server can handle at the same time can be a surprise to you.

Another great advantage of server virtualization is the ability to transfer a running virtual server between multiple physical hosts, balancing the load and facilitating maintenance. You can also use snapshots of virtual servers to keep an up-to-date status of the running servers before making changes, such as software updates. If anything goes wrong, you just go back to the snapshot and the affected server works as if nothing happened. Obviously, this method can save a lot of time and avoid a lot of trouble.

If you haven't been on the road to virtualization before, don't be afraid: There are more choices in front of you than ever before.

One, on the desktop or laptop computer to try a small.

While server virtualization is clearly in the server room, there are a number of ways you can bring virtualization technology to the small office environment, that is, the introduction of the desktop or notebook computer.

Today's desktops and laptops have a surprisingly large amount of unused resources when it comes to easy tasks such as receiving e-mail or browsing the web. If you feel you need to run a different operating system (for example, to support legacy applications), you can start the virtual desktop on the local system and temporarily discard the physical desktop.

This workaround is especially useful when you encounter application compatibility issues that are caused by running older code on newer operating systems. To try it for free, you can download the PC version of VirtualBox (http://www.pcworld.com/article/221338/create_virtual_machines_easilyand_for_ freewith_virtualbox_4.html).

Second, the establishment of a small, possibly free test environment.

If you've recently discarded several servers, it would be nice to have them serve as a platform for you to start creating a virtualized test environment. The key is to make sure that they have a few gigabit NICs and that they have as much memory as possible. Virtualization technology often consumes less processor resources, but consumes more memory resources, especially if you use a virtualization approach that does not use memory page sharing to make the most of your physical memory.

If you happen to have no extra servers on hand, try a cheap new server (as well as a lot of RAM). If you're bold, you can even build a server out of spare parts. In a test environment, this machine acts as a proof-of-concept system, but does not run it in a production environment.

As for the choice of virtualization software, you can try it on the test system one by one. If you have a few hard drives, you can install VMware ESXi, Microsoft Hyper-V, Citrix XenServer, or Red Hat Rhev on each hard drive, just to see which software is best for your needs each time you boot to a disk. All of these packages offer a free or trial version (you can try it for at least 30 days).

Third, the establishment of their own shared storage systems.

When you use a virtualized framework with multiple physical host servers, you need some kind of shared storage system to fully gain the benefits of virtualization technology. For example, if you want to be able to migrate virtual servers between physical hosts, the storage systems required for those virtual servers must reside on shared devices that are accessible to each host.

Some virtualization technology scenarios can support many storage protocols, such as NFS, iSCSI, and Fibre Channel. If you are testing or testing, you can simply add several hard disks to Windows or Linux systems, share them with NFS or iSCSI, and bind the test server to that storage system. If you need a more comprehensive "autonomic" approach, try open source storage solutions such as FreeNAS. The software provides a simple way to add a large number of storage systems to the test network and production network, with a cheap hard drive.

Iv. be familiar with the test environment.

With some kind of shared storage system and at least two physical host servers, there is the foundation of a standard virtualization technology platform that can be used at any time. If you're evaluating several different packages, try running them for a week or so. Be sure to try out all the features that are important to you, such as Virtual server live migration, snapshots, virtual server cloning and deployment, and high availability.

You may also be able to test the production workload in a test environment to see how the platform works in real-world environments. You can build a database server, run several reports using a backup of a real dataset, or use a Web server benchmarking tool to measure the performance of a Web application server. This approach not only allows you to familiarize yourself with the day-to-day operation of the virtualization technology platform, but also gives you an idea of what resources the virtual server might need after entering the production environment.

Even if you start to enter the production environment, you have to keep the test environment.

After you have done this, you may have chosen a solution that you want to use in your production environment. You've got a rough idea of management tools, and you've planned how to do the actual work, but it's not time to dismantle the test environment.

Once you start buying new hardware for your production infrastructure, you will need to make sure that the virtual servers you plan to deploy can handle the tasks assigned to them in the future, referring to the settings that are made in the test environment.

In addition, once you have finished building your production infrastructure, you can test new features, updates, and other aspects with a test environment that will only enhance the stability and reliability of your production platform.

(Responsible editor: The good of the Legacy)