ltstudiooo - Fotolia
Virtualization promises vastly improved utilization of computing resources, but those resources are never actually free -- every virtual machine consumes memory, processing cycles, storage and network I/O regardless of how much value the VM actually provides to an enterprise. As organizations embrace and develop a virtualization strategy, it is critical to recognize the concept of VM lifecycles and deploy the infrastructure and internal policies needed to manage VMs throughout that lifecycle. This ensures corporate computing resources are utilized in the most beneficial, efficient and cost-effective manner.
What does VM lifecycle management involve?
When users think about VM lifecycle management, they often think it's strictly about finding and removing old VMs. Although end-of-life (EOL) considerations are a part of VM lifecycle management, the overall practice involves all aspects of the creation, optimization, management and eventual decommissioning of VMs within the enterprise. There are four major parts of the VM lifecycle.
VM lifecycle management usually begins with a justification process long before a VM is ever created. Even though VMs are fast and easy to create, it's important to ensure that each specific VM is worth deploying, has a clear picture of its resource needs and value to the business and understands how long the business should need the VM. Some companies impose chargeback or other mechanisms to help business units prioritize and budget for workload computing. Organizations that omit justification or allow VMs to be created without management oversight will inevitably waste valuable computing resources.
Once a new VM is approved, it can be provisioned (created) by an authorized IT administrator. Limiting the number of staff that can create VMs helps avoid confusion and allows better VM organization. The actual process takes only minutes and several mouse clicks, but it represents a commitment of processing, memory, storage and I/O bandwidth -- costs to the business. In addition, each new VM imposes collateral overhead in data protection including clustering, snapshots, replication, disaster recovery and so on. When a problem occurs, it's one more VM to recover and spend time on.
Once a virtualized workload is running, changes in utilization over time (such as a growing database or a larger number of users) can lead to reduced performance, so IT administrators must monitor VM performance on an ongoing basis. Most VM lifecycle management tools are capable of producing warnings and alerts when resource thresholds are reached, and administrators can easily adjust resource levels or even reprovision an expanded VM to replace the existing one.
Ultimately every VM should be reviewed periodically to evaluate its continued value to the business. This phase usually begins around the time discussed in the original justification, and it involved VM stakeholders, IT administrators and business leaders. If the VM is still providing value, it may be continued for an agreed period (perhaps another six months or a year). If the VM has fallen into disuse or has been supplanted by other tools, a decommissioning plan is usually put into place to park the VM and relegate it to long-term storage. This frees active computing resources for other workloads and reduces resource growth which mitigates more capital investment in servers and other hardware.
Dig Deeper on Virtual machine performance management
Related Q&A from Stephen J. Bigelow
Containers have rapidly come into focus as a popular option for deploying applications, but they have limitations and are fundamentally different ... Continue Reading
ALM and SDLC both cover much of the same ground, such as development, testing and deployment. Where these lifecycle concepts differ is the scope of ... Continue Reading
Eliciting performance requirements from business end users necessitates a clearly defined scope and the right set of questions. Expert Mary Gorman ... Continue Reading