While there are many advances in enterprise computing accredited to virtualization technologies, administrators are finding difficulties in 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—you’d have one license per physical server.
However, as single physical machines began to host multiple virtual machines running numerous server instances, software licensing entered murky waters. Further complicating matters is the flexible and dynamic nature of virtual machine management. Depending upon available hardware computing resources, a virtual machine could be operating within the confines of one physical environment at one moment and then seamlessly move to another physical machine when resources on the current host machine become low or are unavailable. Similarly, a single machine could be hosting multiple instances of servers.
Out With The Old
“The old metrics don’t work anymore,” says Christof Beaupoili, one of the founders of Aspera, a Germany-based 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, in the past, many organizations focused on scanning solutions to find out what was installed on the machines, but that type of 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, new tools and models for managing server licenses in virtualized 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.
In With The New
To help reduce the complexity of license management for virtual machines, 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.
Yet other virtualization vendors have their own technologies and licensing agreements that only offer extensive virtualization advantages in a homogeneous infrastructure. “If you look into the IBM license, it states you are allowed to license the capacity for only IBM virtualization technologies,” says Beaupoil.
“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.
“Right now, the license conditions change very quickly, and sometimes that’s good, and sometimes that’s bad. Right now it makes a lot of difference what virtualization technology you are using. It has an impact on the license condition of the product that you run on that virtualization technology,” concludes Beaupoil.