Admins usually start by earning a certification for their virtualization platform of choice. But that may not be enough. A hypervisor is only one part of a much larger architecture, and virtualization admins should understand how a hypervisor interacts with guest OSes, applications and the network. IT certifications in these other areas can help you round out your virtualization skills.
IT certifications for operating systems
Whether your organization uses Windows, Linux or something else, every virtualization administrator should have an OS certification. Server virtualization is all about resource allocation, so admins need to know how to examine a virtual machine (VM) to determine whether its guest OS has the right amount of hardware resources.
Of course, performance benchmarking is just the beginning. Most organizations strive to achieve optimal VM density on host servers, which means optimizing guest OSes and disabling unnecessary OS components. IT certifications for the OS can help you improve these skills.
Basic networking certifications
Most hypervisors support the virtualization of networking components such as network interface cards (NICs) and switches. Pursuing IT certifications in networking can help virtualization admins recognize network-related challenges.
Hardware limitations might prevent administrators from dedicating a NIC to each VM, for example, so several VMs may have to share a NIC. In this situation, it’s often advantageous to offload some traffic from the physical network to a virtual network to prevent bandwidth saturation.
Some admins have also discovered that as they perform physical-to-virtual server conversions, they may be forced to implement virtual LANs to maintain the same logical network topology that was in place before servers were virtualized.
For IT certifications that can boost your network knowledge, there is Microsoft’s Exam 70-642 (MCTS: Windows Server 2008 Network Infrastructure Configuration), which tests general networking for Windows Server 2008. If you prefer an OS-neutral, vendor-neutral networking certification, I recommend the CompTIA Network+ certification.
Virtualization admins may also benefit from earning IT certifications for specific applications. These IT certifications ensure that you know an application’s system requirements can make it run efficiently.
More important, some software publishers specifically address server virtualization in their support policy. Unless a virtualization administrator has studied an application well enough to pass a certification exam, they might assume the application runs well when virtualized, which isn’t always true.
Microsoft Exchange Server is a classic example of such an application. You can virtualize Exchange, but Microsoft does not support virtualization for the Unified Messaging Role. There is nothing stopping you from running a virtualized Unified Messaging Server -- it actually seems to work quite well -- but doing so can put your Exchange organization in an unsupported state.
There are no firm guidelines for what IT certifications a virtualization admin should earn, but there’s no denying that server OS, application and basic networking certifications can be beneficial. So don’t stop at virtualization certifications. Go for some broader IT certifications as well.
This was first published in April 2011