Virtual Plant Best Practices for Virtualization in Process Automation
Virtual worlds have until now mainly been known from the field of computer games. But through information technology, they have also found their way into industrial automation. What are the opportunities and risks of a production plant in a virtual environment and how can virtualization solutions be implemented?
The concept of virtualization has its origin in the world of information technology (IT) and describes the emulation of hardware, operating systems, data storage and networks. It helps to distribute computer resources more purposefully, to combine them clearly, or to run virtual operating systems within a host operating system.
The IT world is developing rapidly — driven by increasingly complex software that requires more and more hardware resources. This means the number of computers is constantly growing, which in turn results in higher expenses for administration, space and service. A typical example is a company computing center which manages hundreds of computers. Another dimension of the complexity is caused by different life cycles and hardware versions (PC technology), operating systems such as Windows NT, XP or 7, as well as the wide range of application software. This situation made it easy for the innovative technology of virtualization to take a hold. It not only optimizes administration, space and service, but it also makes for more efficient use of resources such as CPU, memory and storage space and ultimately results in cost savings.
Virtualization: The Impact of the IT Revolution on the Process Industry
This expanding IT world in companies has increasingly penetrated the domain of industrial automation — with the objective of passing along the benefits and, in particular, the cost savings to the production world.
Production plants are under particular pressure to lower costs and demand low investment expenditure, fast commissioning and optimal operation without production downtimes.
A virtualization solution starts with higher IT investment for host systems, virtualization software, maintenance contracts, and possibly also for cooling, air conditioning and noise control for the high-performance host systems. This investment usually pays off during the life of the plant. Companies implementing virtualization solutions typically have dedicated IT departments with highly trained specialists. Special knowledge of process automation is also required, as demonstrated by the following two examples:
- Functions commonly used in the IT world, such as moving applications in runtime for the purpose of load distribution (vMotion) or pausing a client or server (suspending), cannot be easily carried over to the production environment.
- When high-availability servers are operated in a virtual environment, certain aspects of availability must be taken into consideration. Redundant servers should run on different host systems, such as different computers or blades, to prevent “single points of failure”.
There is no catch-all answer to the question of when virtualization makes sense or becomes efficient. The specific requirements of the project always determine the required approach. There are aspects such as space requirements, remote access, energy savings, validation, and distribution of the plant; but also the existing infrastructure, or the operation of other applications in a virtual environment such as analysis utilities as well as information and reporting systems.