Server virtualisation is a mature technology that can help you save money, time, and carbon emissions. Consequently, just about every major organisation has adopted it in one form or another, somewhere on their IT estate.
But there is a major issue with virtualisation that many organisations overlook – the impact it has on your software licensing. Unless you are fully aware of these implications and able to manage your licence position, you could end up paying more for additional software licences (and fines if the shortfall is discovered during an increasingly common vendor audit) than you saved through virtualising in the first place.
Understanding the risks
Most software vendors' licensing rules differ between physical and virtual environments. But a common theme is that small changes to the virtual environment can have a large impact on licensing requirements. Typical examples include:
• Hardware, e.g. additional servers or CPUs in a cluster
• Server mobility within server farms, e.g. DRS/v-Motion enabled
Converting a physical device to a virtual device changes the licensing requirements and you need to check your licence agreement to discover what the full implications are. You also need to consider maintenance. Some vendors, such as Microsoft, now require active maintenance on server applications deployed within server farms (Microsoft Exchange server etc.).
Questions you have to consider before virtualising
Do you have the ability to track the movement of virtual servers across the server farm?
In the event of an audit you may be required to prove that specific servers are not breaching any licensing requirements by moving within the server farm.
Vendors such as Oracle document what they recognise as 'hard' and 'soft' partitioning, which need to be understood so that you can consider how to track, or limit, the movement of virtual servers as appropriate to your needs.
Do you consider the licensing implications when designing new or upgrading existing server farms?
Having clarity of the impact of virtualisation on the vendor products you are virtualising can feed into the overall design initiative, thus understanding the additional, or reduced, costs.
Do you consider the licensing implications when deploying new OSE (Operating System Environments) within the server farm?
Is the server farm a dedicated test or development environment? As there are different license requirements for these.
Does Windows Server moving from per processor to per core impact you?
There a number of ways to license Microsoft SQL Server within a virtual environment; what’s the best option for your organisation?
Virtualisation is here to stay and the benefits of implementing it can only increase. So, if you are planning to implement it, do make sure you consider the impact on your software licensing position and take any additional costs into account for your final cost/benefit analysis.
Russell Fry, Marketing Manager at Certero