Details of the private cloud

Cloud computing in the country has an interesting phenomenon, it set off a boom in the technology sector, but also produced a lot of "Chinese characteristics" of "literature" works, see the scholars, executives and experts farsighted cloud computing forecasts and top-level design. They tend to be of a certain Chinese character, the narrative structure of the form of neat (such as "cloud Computing 12345"), the use of parallel sentences (such as "cloud Computing and Sea Computing"), analogy (such as "using the cloud Like Water") and the slogan ("The Rotten Machine Cloud").

However, the ideal fullness of reality but can not help but the bone, the real world is not as neat as the imagination, the practice of the "big place" focus, often easy to ignore the fatal "details", found that the problem is often hard. The purpose of this paper is to talk about these details briefly. Due to experience limitations, this article covers only the "infrastructure as a service (IaaS)" type of private cloud.

The details of saving money

Before all projects begin, think clearly why. "Saving investment", "reducing TCO ownership" is often the selling point of private clouds, which involves calculating ROI (return on investment), or taking into account the net present value of the industry benchmark discount rate (NET Present Value). This type of analysis usually requires a certain amount of expertise, so cloud vendors also provide some automated tools to help IT staff who lack this knowledge to compute. However, if you do not pay attention to details, often in long March first step on the somersault.

In a small project where 19 servers will be P2V migrated, we use VMware's ROI TCO Calculator (http://roitco.vmware.com/vmw/) to calculate its Roi, and to enter relevant parameters through the page, The ROI is 185% and the return cycle of investment (payback) is 1.7 years. As a result, such numbers are encouraging, but careful analysis reveals some of the following hypothetical flaws that lead to the distortion of the final result.

Some of the additional software costs generated by virtualization (such as Windows Server, database, and so on vcenter) are not counted.

The calculation of tariff revenue ignores the new costs of shared storage (storage devices, fibre switches, etc.) in the virtualization architecture. At the same time, the benefits of DPM (Distributed Power Management), which is similar to that of the source management, are hard to cash in real-world applications (the ROI TCO Calculator computing tools are used to save nearly 21.5% of the power from DPM).

Although the efficiency of server management has been improved, it has not been implemented to the reduction of specific operational personnel, the income of human cost cannot be cashed, etc., while the cost of operation and maintenance of shared storage is not taken into account.

Space cost ditto. The lack of consideration of shared storage (storage devices and fibre switches, etc.) creates new space requirements.

Because the shared storage is to be built, the analysis tools are converted using the "per-unit storage Valuation" x "Storage unit", and the cost estimates are lower than the actual situation (storage required for new purchases).

In the calculation of the four-year cycle, and not because of the efficiency of the reduction of operational personnel, at the same time, customer-owned room, free space can not be produced in the real cost of discount.

Thus, after deducting these benefits, it was found that ROI was only 45% and the return cycle for investment (payback) was 2.8 years. This result will become more pessimistic if the net present value NPV is considered in the industry benchmark discount rate conversion.

This phenomenon is actually a common problem in private cloud deployments: Virtualization's apparent hardware consolidation gains are neutralized by expensive virtualization software, new hardware (such as shared storage) and new environments (such as hosting Vcenter 2008 and databases), while server operation is more efficient, but in storage, New technology mastery and adaptation, but also will generate a fresh human cost input, so that the cost of persuasion decline. These details, in the early stages of the budget, may be pushed by the manufacturers of new technology products and services intentionally and unintentionally hidden. If they do not undergo a careful digestion, often based on the wrong idea to start into the project.

Therefore, in the face of private cloud projects, to avoid the parrot, such as professional ROI analysis tools also have some shortcomings, not to mention some experts lack the basis of the forecast. Only by facing the reality of "not saving money" directly can we further stimulate the potential of further details and plan "micro-operations" to achieve greater benefits in the planning phase. In this respect, there are some suggestions.

Hardware Rating: Non-production environment is the most "snails in the shell to do the dojo." Many enterprises, the application of the grading is more clear, there will usually be production, production, test development, training and other environments, but many times when the host of these environments often appear overkill, the production environment is often the same as the same hardware. In fact, the hardware, you can not consume expensive shared storage, because server local storage is often in the virtual platform after a large amount of idle, used in the development of test environment can also be competent.

Software Rating: In addition to the hardware on demand to classify the use, the software level can also adopt the same strategy. If you are using a trial version of the virtualization layer, or increasingly sophisticated open source software to further reduce costs. An international semiconductor company used in the world's hundreds of laboratories in the test bed private cloud, it is set up on the ESXi trial version.

Enhance operational personnel's "micro-operation" skills: encourage operators to master some quick and easy skills, even in the absence of vcenter, through the ESXi shell can also achieve the cloning, migration and registration of mirrors; In the absence of commercial backup software, By using some open source scripts to automatically back up virtual machines and so on, use full cloning and chain cloning details to enhance the cost effectiveness of non-critical business management.