What’s stopping you from embracing virtualization? The potential cost savings and the ability to rapidly respond to changing business environments provide an unprecedented level of agility. The reality, however, is that managing a virtual environment also creates significant challenges.
In fact, respondents to a recent Gartner Data Center Conference Survey cited “controlling virtual machine sprawl” as their biggest challenge to managing server virtualization environments (see “Addressing the Operational Challenges of Virtual Server Management,” Cameron Haight, Feb. 27, 2008).
Without proper controls, virtualization increases business risk. The potential for service disruptions, noncompliance with corporate policies and government regulations, and costly server sprawl is higher in a virtualized environment. As a result, IT must establish and maintain effective controls. However, too much control inhibits agility, but too little control exposes the organization to risk.
So how do you achieve the right balance between agility and control for your virtualized environment? We recommend the following seven guidelines. Please note: While the issues in this article were observed in VMware environments, they also have some applicability in other arenas, such as z/VM:
1. Address all types of change: Changes occur through manual and automatic activities and they need to be addressed.
• Planned changes are anticipated and scheduled in advance. The manual provisioning of a new physical server and an update to a server operating system are good examples.
• Unplanned changes may be anticipated, but they aren’t scheduled ahead of time. A manual fix to restore a failed server and automatic failover are examples of unplanned changes.
• Authorized changes have all the proper approvals in place. Moreover, if they’re manual changes, they’re performed by a person authorized to make the change.
• Unauthorized changes don’t have proper approvals, or they’re performed by someone not authorized to make the change.
An effective service management approach accommodates all four combinations: unplanned/unauthorized, unplanned/authorized, planned/unauthorized, and planned/authorized.