Archive for category virtualization
There has been a lot of discussion lately about “service virtualization”, however the term alone can make your head spin. Are we talking about server virtualization? What types of services are involved? What does virtualization have to do with testing? I’d like to quickly clear up any confusion you may have. Service virtualization is used to simulate the behavior of components in an application so you can perform an accurate and timely test in a world of complex interrelated applications. Production services that may not be available for integration testing can be virtualized so the testing can take place at an appropriate time in the software development process.
While quality professionals have always needed to test combinations of code, current methods for writing and combining code have changed so much that traditional approaches to testing can’t get the job done at the right price and the right time. There is a fast growing commercial market for production services that are incorporated as self-contained modules into software applications. Third party services such as PayPal or a credit checking service are increasingly used in customer facing applications.
Use of these third-party services increases the efficiency of software development, but at the same time makes your application dependent on services that you do not control. Consider, for example, the scenario of an online retailer with multiple suppliers. The retailer has created a new mobile application for customers. This application uses a credit check service provided by a third-party vendor. The team can’t test without this dependent component, but it is not available for testing. Without service virtualization, the software development team has some difficult choices to make and none of the options are good. If the development team proceeds without doing the necessary testing, they may introduce errors that are much harder and more costly to fix later on. If the team waits until the third-party service is available, developer productivity will decline and the team may miss production deadlines. In addition, if the third-party service becomes available it can get pretty expensive to test application performance at high usage levels since the service costs money each time it is executed.
So what does the development team do in this situation? Service virtualization is a new approach to testing that helps organizations eliminate some of the testing bottlenecks that make it hard to bring new high quality applications to market quickly. Here are five key things you should know about service virtualization.
- To get started with service virtualization you need to understand your testing methodology and think about where service virtualization can increase team velocity while also helping your team to deliver higher quality software.
- Use a cost/benefit analysis to select which services should be virtualized. Consider the cost to your company when testing is delayed because dependent services or software are not available for testing. How much is spent on staff needed to set up and maintain test environments? How much do you spend to maintain test environments that are not fully utilized? What is the cost for software licenses in the physical test lab environment? What is the cost of third-party service access fees?
- Service virtualization can help you find errors in all testing phases- including unit testing, performance testing, integration testing, system testing, system integration testing, user acceptance testing, and operability testing.
- Recording a service that already exists is a great way to define the behavior of your virtual component. You can use the recording process to identify the behaviors that will need to be simulated so you can create test cases quickly.
- You can’t expect to virtualize all your components. Therefore, you need to be able to easily move back and forth between real components and virtual components while you are testing. You want to maintain consistency across real and virtual components.
One of the biggest impacts of service virtualization for developers is the ability to validate integrations much earlier in the application life cycle. The software development team can move beyond unit testing and overcome many of the roadblocks that inhibit timely, efficient, and cost effective testing.
Recently I talked with several data center managers about their experiences with virtualization. While these managers have different perspectives, they all agreed that server virtualization alone isn’t enough. By moving beyond server virtualization to a more holistic approach including virtualizing storage, network and other technology assets, these companies are increasing the ROI of their virtualization implementations. There is an element missing in their virtualization strategy that is making it hard to meet the increasing demands of the business. These companies are beginning to reset their virtualization priorities to make sure that all the elements of the IT environment work together – and this includes creating a virtualization environment that automatically allocates resources based on the demands of specific applications and workloads.
IT management needs to focus on the application priorities in terms of performance to support the business. If all your applications are treated with the same priority– how can you be assured that your most critical applications always have access to the resources they require? You may be doing a great job monitoring CPU usage and available memory in your server virtualization environment, but still have unexpected performance problems that impact critical customer applications. What’s missing is a way to adjust for business priority variations when you allocate resources across your virtualized environment.
One way to ensure that your environment operates with an increased awareness of the requirements of each specific application is to implement application infrastructure virtualization. It is a capability that allows for codifying business and technical usage policies to make sure that each of your applications leverages virtual and physical resources in a predictable way. By automating many of the underlying rules and processes, you can optimize both resource utilization and the customer experience at the same time.
There are three main characteristics for application infrastructure virtualization:
- Setting business priorities for applications and automatically adjusting resources to keep customer service levels in balance
- Applying a customer focused approach to the automation of resource optimization so that each application gets the resources it needs based on resource availability and the application’s priority to the business
- Allocating a pooled set of resources to support a group of workloads.
Application infrastructure virtualization ensures that any resource can run any workload. If there are resource limitations then application with the lowest business priority at the time is allocated with the fewest resources.
I amplified this issue in a white paper I recently wrote for IBM on the topic. The paper, called Creating Application Awareness in IT Virtualization Environments, discusses application infrastructure virtualization and how companies can combine server and application infrastructure virtualization to improve overall performance levels. In addition, the paper describes IBM’s solution for application infrastructure virtualization, IBM WebSphere Virtual Enterprise (WVE).
It is easy to assume that server virtualization itself is enough to solve resource management issues in the data center. However, it is increasingly clear that virtualization has to be tied to the performance of various applications based on the times and situations where they demand performance. Tying application performance to virualization creates a more efficient and proactive environment to satisfy customer expectations.
Many business executives are interested in moving to the cloud because of the potential impact on business strategy. Increasingly they are convinced that a cloud model – particularly the private cloud – will give them an increased amount of flexibility to change and manage the uncontrolled expansion of IT. In contrast, from an IT perspective, the ability to virtualize servers, storage, and I/O, is often viewed as the culmination of the cloud journey. Of course, the world is always more complicated than it appears. Cloud computing if implemented in a strategic manner can help a company experiment and change more easily. Likewise, virtualization, which may seem like an isolated and pragmatic approach, needs to be considered in context with an overall cloud computing strategy.
However, the challenge for many companies right now is how to transform their virtualized infrastructure into a private cloud that delivers on the promise of on-demand and self-service provisioning of IT resources. To make sure that business leaders gain desired cost savings and business flexibility while IT gains the optimization that can be achieved through virtualization requires an integrated strategy. At the heart of this strategy is service management of this emerging highly virtualized environment.
Why is service management important? There are good reasons why a key focus of the virtualization strategy at many companies has been on server virtualization. For example, server virtualization helps companies create a faster and more efficient IT provisioning process for users. It helps users with increased operational flexibility based on the mobility and isolation capabilities of virtual machines.
However, there is a major management problem with the typical virtualization approach in many companies. Often developers satisfy their demands for computing resources by simply creating or spinning up a new virtual machine rather than anticipating that they might not have the time or money to purchase new IT systems. IT management in the beginning allows this practice because it is easier than trying to control impatient developers. However, there is a price to be paid. Each new virtual machine image requires memory and disk resources. When the number of virtual machines grows out of control, companies end up spending more time and money on disk, storage, and memory resources than was anticipated. Lack of control means lack of management. What is the answer?
At a recent IBM systems software meeting, Helene Armitage, General Manager of Systems Software, emphasized that in order to truly transform the data center into an agent of change requires a focus on manageability. Here are the main take always from my conversations with Helene and her team.
- Virtualization is not just about server consolidation. Companies need to think differently about virtualization in order to prepare for a future marked by rapid change. For example, storage virtualization can offer big benefits to companies facing explosive demand for data storage from increased use of new technologies like embedded and mobile devices.
- Physical and virtual environments will need to be managed in a unified way and at the same time. Some may think of virtualization as a way of reducing management requirements. After all, with consolidated resources you should have less demand for power, energy, and space. However, management needs to be done right to be effective. it is important to consider how to manage across the platform and to include monitoring and configuration in combination with business service management – delivering IT services in a structured, governed, and optimized way.
- Cloud changes the complexion of what’s important in how virtualization is approached. In the cloud, virtualization takes on a different level of complexity. If elements of virtualization including storage, server, and I/O virtualization are handled as isolated tasks, the cloud platform will not be effectively managed.
- System pooling is key for managing lots of systems. Systems pooling essentially means that IT treats all resources as a unified set of shared resources to improve performance and manageability.
- Enforcing standardization right from the beginning is a requirement — especially when virtualization is at the core of a cloud environment. The only way to truly manage the virtualized environment is to apply repeatable, predictable, and standardized best practices across the entire computing environment.
The greatest challenge for companies is to think differently about virtualization. Management will need to realize that virtualization is a foundational element in building a private cloud environment and therefore has to be looked at from a holistic perspective.