One area of huge potential cost savings in virtualized and private cloud infrastructure is software licensing. Many organizations don’t plan VM placements with an eye towards reducing licensing requirements. And when you are licensing by CPU or core, such as for Windows Server, Microsoft SQL Server or even Oracle licensing, it really does pay to both maximize VM density on licensed physical servers and ensure the VMs are contained to licensed servers. We have found an average savings of 55% of licensing requirements using Cirba’s analytics to do the placements.
But what about when DRS is active? While programmable rules exist within DRS to contain a group of VMs to a group of hosts, DRS doesn’t know how to stack workloads in order to maximize density. DRS can’t tell you how many hosts you require, nor will it understand changes over time as VMs enter and leave the environment. So, key pieces of the puzzle are missing here in order to really enable you to control license requirements in these dynamic environments.
A better way is to leverage Cirba’s software license control module to optimize VM placements. Cirba maximizes VM density by playing “Tetris” with the workloads to safely fit them together, to make the best possible use of capacity without competing for resources. Cirba ’s placements respect license requirements, even when rebalancing. And Cirba also ensures that as the environment changes over time (VMs coming and going), you can see the impact on the host requirements. In environments where DRS is active, Cirba automatically pushes its software license placement “rules” to automatically program DRS. This enables you to use DRS as a load balancing safety net (which isn’t really required with Cirba) without violating licensing requirements.
Check out this video in which Andrew Hillier gives an overview of Cirba’s Software License Control module.