Are there any dangers or problems involved with multi-hypervisor management in the data center?
Considering the advanced state of virtualization technology today, it is rare that one hypervisor should not coexist with others in the environment. The biggest disconnect is the absence of VM interoperability. For example, a server deployed with Hyper-V will not load and run an ESXi virtual machine -- that ESXi VM will have to be started with or migrated to another vSphere system.
The bigger dangers lie in costs and IT staff burden. Remember that although a second hypervisor can be tested and evaluated with little direct cost, the actual hypervisors used in production or elsewhere in the enterprise will also need to be licensed. Since this reduces the total number of servers virtualized by the primary hypervisor, you may find that adopting a second hypervisor could jeopardize your volume license deals -- actually raising the total cost of virtualization.
In addition, the second hypervisor will need to be managed, and this demands capable management tools. It is possible that a third-party management platform already in place will support the second hypervisor. If not, however, you must either adopt a new tool that will support multiple hypervisors, or bring in a second management tool to support the second hypervisor. In either case, this means additional costs to purchase and license new management tools.
Beyond the cost issues of management tools, an IT staff is then faced with the challenge of mastering a new or second management platform. It's certainly possible, but it will take time for IT personnel to make the adjustment. In the meantime, errors in VM provisioning, configuration, protection and other management tasks will be inevitable. And there is also the danger of staff specialization, where only a few administrators master the new tool. This might impair management activities if those personnel are unavailable for any reason.
This was first published in April 2013