Voice of the DBA

Tag: virtualization

  • Future Virtual Machines

    Vritualization madness can be very handy

    I recently virtualized my Windows Home Server. I have had multiple boot drive failures, and I was getting tired of reinstalling the product. So I installed VirtualBox, then created a series of virtual disk drives and set my home server back up. It’s built on RAID 1 drives, so I’m hoping that it will last a long time, and even migrate to newer hardware over time.

    On my laptop and desktop, I use VMWare to build test machines, and then use them for various versions of SQL Server in presentations. I can easily make changes in a VM on the desktop, copy the VHD files to my laptop, and then have the same environment ready when I deliver a presentation. Over the last ten years, virtualization has become a fantastic test environment for me and I can’t imagine doing without it. On the server side, I haven’t even noticed the migration of the SQLServerCentral servers from physical hosts to virtual machines, and they have performed very well.

    However in one sense, nothing has changed for me on the server side. Our VMs are over provisioned, to prevent issues with the performance, just as they often were with physical machines. I suspect that is the case with many other virtual SQL Servers out there in production. However I’m not sure it’s a bad way to deploy VMs for a database server, especially with hardware so cheap.

    I ran across a series of reports on the hypervisors of the future, which talks about the changes from the various vendors, and has a large section devoted to desktop hypervisors. It’s an interesting read, though quite a bit of the information is related to open source products. On the Windows 8 front, the Hyper-V changes look good, but I worry that licensing might prevent most of us from taking advantage of the enhancements.

    I find virtualization to be an amazing way to get more work done on a desktop, in a very stable manner. I can test software in a VM and then remove it, or delete the host if the software causes issues. I can also simulate a large amount of hardware with much less effort than in the past. I urge you to try some virtualization software and experiment with the capabilities. Whether you build experience by working with software you can’t install elsewhere, or just learn some of the capabilities of the virtualization software, it will help you at some point in your career. I only expect there to be more and more VM deployment in all companies over the next decade.

    Steve Jones

  • The Virtual Lab

    Over a decade ago, when the startup company that I worked for went bankrupt, I received a few servers and some other hardware as a partial severance. At the time it seemed like a good idea, and it was nice to have a few spare servers on hand. I would later use some of that hardware to work on SQLServerCentral. My wife, however, wasn’t thrilled since spare hardware, even powerful hardware, doesn’t buy groceries.

    These days the pace of technology change is high. SQL Server is a stable platform that many companies might install and use for a decade, but it seems we have new features to learn every 18-24 months as new versions are released. I think more and more of us have to understand a wider variety of features and platforms all the time, even if we use them sparingly. For many of us, that means some sort of lab if we want to gain any sort of skill with the products.

    One of the best things about virtualization, in my mind, is that it enables the average professional working with technology to build a huge lab for a fraction of the cost that it would have cost a decade ago. A relatively modestly priced laptop, something in the $600-800 range, will run most any technology you need, including Windows 2008 R2 Data Center in a VM. If you wonder how you can do this on a budget, check out Denny Cherry’s article on building a lab with VMWare or the Virtual Server series on SSC. You could do the same thing with Hyper-V or Virtual Box, and a subscription to MSDN or TechNet, something many of us get from our employers. If you don’t have access to those programs, there are evaluation editions of almost all software you can use.

    With an external hard drive, you could even have a portable lab that you can take with you anywhere.

    Steve Jones

    The Voice of the DBA Podcasts

  • Fast Migrations

    No matter if Hyper-V or VMWare are faster, competition will spur innovation.

    Virtualization is becoming more and more popular all the time, and if you don’t know much about this technology, I would highly recommend you begin learning. In fact, if you are a technology worker, you ought to have some sort of virtualization software installed on your computer right now. Testing, practicing, learning, all of these are made easier with a virtual machine that allows you to try out ideas without affecting your daily work.

    One of the advantages of virtualized servers is that they can be moved from one set of physical hardware to another. If you find that your virtual machine (VM) is not receiving enough resources from the host, you can move it to another less busy host, and improve performance. What’s even more amazing is that you can move this VM while it is in use. In fact, your clients may not even notice that the VM has migrated to another host, even while connected. To me, that’s absolutely amazing.

    The way it works isn’t important, but how quickly and smoothly it moves is important. VMWare and Hyper-V both support this live movement, and this might be the place we find the next race to speed up performance from software vendors. According to this article, the latest version of VMWare can move hosts five times faster than Hyper-V. Whether that’s true or not, I think it’s good that there is competition in this area, spurring innovation and research into ways that we can improve hypervisor performance.

    Improving that performance will lead to more applications for virtualized machines, including databases. I know plenty of people that are running SQL Server on a virtual host, and doing so quite successfully. It can be done, just be sure you do a little planning and think about how you virtualize your server. Also be aware of the limitations that exist in the hypervisors and don’t assume every SQL Server instance makes a good candidate.

    As always, test before you make the move, and be prepared for issues to come up, but don’t be afraid of making the move to virtualized database servers.

    Steve Jones

    The Voice of the DBA Podcasts

  • Virtual Security

    The State of New Mexico is being careful with virtual machine security

    I have a few friends that are working virtualize almost their entire computer infrastructures.  They work in large and small companies, but there is a constant push to avoid the bare metal installation of any operating system onto physical hardware, making every Windows or Unix machine a virtual machine on top of a hypervisor. I was surprised to hear that companies were being to aggressive, but the cost benefits can be huge, and when virtualization is done in a smart way, performance doesn’t suffer.

    However virtualization can change security, especially when you have VMs that are allowed to move from physical host to physical host. The state of New Mexico embarked on a similar project, and were concerned over security of the virtual machines. Their department had dismissed some employees because of a security breach a few years earlier and security was on the forefront of their minds. Additional security as well as network controls were used in their project, and I hope they also implemented strong auditing procedures.

    As we move to newer infrastructures that include virtualization, physical security becomes more important, and additional controls are needed. The ability for someone to potentially move a VM outside of a data center, or even to a less secure remote data center becomes a point of concern. Moving the storage itself might be an even bigger problem as virtual storage becomes more commonplace.

    Ultimately, however, we can’t all have dedicated security employees, nor can we expect every DBA, sysadmin or even security officer to be able to protect against and mitigate all attack vectors. Auditing is ultimately the best way to handle breaches. We can’t prevent all of them, but responding quickly, learning, and perhaps more importantly informing the appropriate people to be ready to respond to the information disclosure.

    Steve Jones

    The Voice of the DBA Podcasts