Basic VMware notes

Before Virtualization ,When you walk into a datacenter you will see a crowd of physical servers ,This physical servers need a lot of power,cooling and more work space which is very expensive.

Virtualization is the process of separating the software from the underlying hardware that it resides on,There by giving us flexibility of having multiple  virtual environment that can take advantage of a single physical resource entity .This will allow us to maximize utilization of a resources on a single server  

Advantages of Virtualization

Virtualization allows companies to save
-Time (Time to set-up physical servers much more than VM's)
-Money (We can save energy cost (air condition,electricity,space etc which we spend for physical server)
-Virtualization offers hidden cost saving in the form of human capital and office space

Types of Virtualization

Operating system virtualization - This is the most popular one and also called as server virtualization.In this virtualization,We Install a guest OS on a thin hyper-visor that manages access to hardware resources 

Application Virtualization: Deploying applications without reliance on a installation directly to an operating system.Which means we can run an application on an operating system without installing it.We can gather all dll or registry entries or necessary files that need to run application and put it together in a set of files which give you ability to run application without actually installing it 

storage virtualization- the presentation of logical storage structures that reside on one or more physical storage devises 

What is a Host? 

A host is a computer that uses virtualization software, such as ESX or ESXi, to run virtual machines. Hosts provide the CPU and memory resources that virtual machines use and give virtual machines access to storage and network connectivity.

What is a Virtual Machine?

A virtual machine is a software computer that, like a physical computer, runs an operating system and applications. An operating system installed on a virtual machine is called a guest operating system.

Because every virtual machine is an isolated computing environment, you can use virtual machines as desktop or workstation environments, as testing environments, or to consolidate server applications.

In vCenter Server, virtual machines run on hosts or clusters. The same host can run many virtual machines

What is a datastore?

A datastore is a logical container that holds virtual machine files and other files necessary for virtual machine operations. Datastores can exist on different types of physical storage, including local storage, iSCSI, Fibre Channel SAN, or NFS. A datastore can be VMFS-based or NFS-based.

You can create a new datastore by formatting LUNs or by mounting NFS volumes to an existing host. In addition, you can add a host with existing datastores to the inventory.

What is the Networks view?

This view displays the set of networking objects available on vCenter. Using the Networking view, you can create and manage networking with vSphere Distributed Switches and view networking with Standard Switches configuration.

vSphere provides two types of network architecture. Networking with vSphere Distributed Switches manages virtual machine and host networking at the datacenter level, while networking with Standard Switches manages virtual machine and host networking at the host level.