This white paper has three main goals. The first is to generate a better understanding of the cloud in both the business and IT communities. The second is to describe the major components of vCloud and the virtual datacenters they provide. The third is help businesses visualize and understand how vClouds could be beneficial in addressing their specific IT needs.
One of today's buzzwords in the business and information technology (IT) communities is "cloud". To many, "cloud" is a positive term, much like a real cloud that relieves us from the intense heat of the summertime sun. But, to others, it is a negative term, much like real black clouds that bring us dangerous thunderstorms. Many think of a cloud as a simple environment that allows businesses to run their applications without having to get involved in underlying infrastructure. Others think of a cloud as a very complex environment that forces businesses to run their applications without the visibility and control of the underlying infrastructure. Part of the reason for varying perspectives is that today's clouds are built upon various technologies, where the cloud providers and technologies' vendors define the cloud differently. This white paper is aimed at clearly explaining clouds built upon VMware vCloud Suite.
This white paper has three main goals.
1. The first goal is to generate a better understanding of the cloud in both the business and IT communities. It describes the cloud using simple, yet effective terminology. It illustrates the cloud by providing simple examples and scenarios. It focuses on clouds built upon VMware vCloud Suite and VMware vSphere Enterprise Plus, which this paper will reference as "vClouds".
2. The second goal is to describe the major components of vCloud and the virtual data centers they provide. It provides simple explanations of how each component interacts through VMware vSphere to the underlying physical components.
3. The third goal is help businesses visualize and understand how vClouds could be beneficial in addressing their specific IT needs.
Introduction to the Cloud
Physical infrastructure is a collection of physical IT assets. It includes items like CPU, RAM, SCSI devices, Storage adapters, Ethernet adapters, and Ethernet switches. In traditional (or legacy) environments, business applications run directly upon physical infrastructure.
Virtual infrastructure is a collection of logical objects built upon the physical infrastructure. For example, a resource pool is a virtual infrastructure object that logically maps to a set of underlying physical CPU and RAM resources residing on a cluster of hardware servers. Resource pools can be used to "carve out" a specific amount of CPU and RAM for a particular use, allowing business applications to run within resource pools.
Cloud provides virtual infrastructure as a service, where sets of virtual infrastructure resources can be allocated for various uses, automatically. For example, a customer who needs to deploy new business applications may be able to obtain the necessary virtual and physical infrastructure automatically, without engaging the IT Team, by making the request through a web portal to the cloud. The cloud may meet the request by automatically manipulating the virtual resources assigned to the customer.
Clouds offer many other features, such as adaptability, availability, security, and manageability. This paper focuses mostly on the cloud's ability to provide virtual infrastructure as a service. VMware defines the cloud provided by VMware vCloud Suite as a "Software Defined Datacenter".
Details on the Cloud
In a traditional environment, business application software runs directly on physical Windows, Linux, and other servers. Each need for a new application typically requires the procurement, installation, configuration, and support of a new hardware server. Each new hardware server typically requires the configuration of supporting network and storage infrastructure, such as the configuration of a port on an Ethernet switch or the creation of a logical disk within a disk array. Once the consumer makes the request for the new server, a great deal of time may be required as the IT Team makes the appropriate procurements and configurations of the hardware, network, and storage resources.
In a virtual environment, business application software runs in virtual machines (VMs) on virtual infrastructure. Consumer requests for new VMs are typically met very quickly by the IT Team, but could require additional time if changes are necessary in the virtual and physical infrastructure. VMs can be rapidly deployed if available CPU and RAM exist in the resource pools, unused space exists in the datastores, available bandwidth exists in the network connections, and available virtual ports exist in the virtual switches. Whenever the appropriate amount of virtual infrastructure is not already available or the new VMs require additional isolation, such as a new network, then additional virtual resources must be configured. Configuring additional virtual infrastructure often requires manipulating the underlying hardware infrastructure, which requires additional time.