While there are many advances in enterprise computing accredited to virtualization technologies, administrators are having trouble verifying that they are operating within the criteria of their software licensing. Prior to the widespread adoption of virtual servers, managing server licenses was a fairly straightforward process—with one license per physical server. However, as single servers now host multiple virtual machines running numerous instances, software licensing entered murky waters. Depending upon hardware computing resources, a virtual machine could be operating within one physical environment then seamlessly move to another physical machine when resources become low or are unavailable.
“The old metrics don’t work anymore,” says Christof Beaupoili, one of the founders of Aspera, a software license management vendor. “In the physical world, the vendors use metrics such as per-install or per-CPU, so hardware-based metrics. Since there is no direct relationship between the software which is running on the hardware anymore, they are switching to metrics that are not hardware-based anymore.” According to Beaupoil, many organizations used scanning solutions to find out what was on the machines, but that technology is no longer sufficient. “A server may be running right now, but in a few minutes, it may not because the virtual instance has shut down, so the main data solution for software-license monitoring is no longer scanning tools.”
To overcome these challenges, models for managing server licenses in virtual environments are emerging. The first wave of technologies for monitoring virtual server licenses has been primarily proprietary. For example, IBM uses a CPU-based capacity model. It uses its own utility—the IBM License Metric Tool—to meter the capacities that the virtual instance is using. Unfortunately, the utility is proprietary, as are most other virtual license managers. Beaupoil points out that tools used to administer virtual environments can also aid in license management. The Virtual Center from VMware is an example. “The new data sources that are identified for capacity can be monitored with a software-license management solution.”
However, Jeff Lauria, Director of IT at iCorps, disagrees. “Ultimately, server licenses are managed in the virtual world the same exact way you manage them in the physical world.” The caveat with virtualized servers is the availability of what Lauria describes as “free server licensing,” which can vary among vendors. “If you buy the Enterprise version of Windows, you’re entitled to four virtual servers,” explains Lauria. This means that organizations that may have 30 virtual servers operating on their networks at any given moment may only need to actually purchase a fraction of the physical licenses.
To help reduce the complexity of software licensing in virtual environments, in August 2008, Microsoft relaxed its server licensing by removing the 90-day license transfer restriction that caused numerous headaches with Microsoft licensing structures in virtualized environments. Previously, all Microsoft licenses were allocated to only physical servers. This meant that when a virtual machine was moved to another server without an available license, Microsoft considered the VM movement a license transfer and could not be legally reassigned to a different physical host for 90 days, thus hampering high availability and live migration of virtual machines. “Many IT shops simply ignored the 90-day license transfer restriction and had never taken the step to purchase additional licenses for the sole sake of virtualizing a Microsoft application,” says Chris Wolf, a senior analyst covering virtualization technologies for the Burton Group.
To further eliminate server license management in highly virtualized environments, Microsoft introduced a data center version of its server software that provides unlimited virtualized servers in a given environment. VMware relies on the physical processors within the hardware to define licensing criteria, making server license management align with infrastructure inventory. As processor manufacturers such as Intel and AMD have released new processor technologies that combine multiple independent central processing units, commonly referred to as “cores,” on a single silicon chip, machine performance has significantly increased, which in turn allows for more virtual machines to be hosted on a single physical machine. Similarly, VMware has structured its licensing policies to reflect this shift and now defines its licensing policies through cores instead of the processor itself. “Although Microsoft treats virtualization one way and VMware treats their product another way, at the end of the day, they’re all keeping track of licenses the same way they do in the physical realm,” adds Lauria. Learn more about virtualization solutions by requesting a free IT consultation.