In this article, we will looking into Vmware Overview, its architecture benefits and different components of VMWare.
What is VMWare?
VMware was founded in 1998 by five different IT experts. The
company officially launched its first product, VMware Workstation, in 1999,
which was followed by the VMware GSX Server in 2001. The company has launched
many additional products since that time.
VMware's desktop software is compatible with all major OSs,
including Linux, Microsoft Windows, and Mac OS X. VMware provides three
different types of desktop software:
VMware Workstation: This application is used to install and run multiple copies or
instances of the same operating systems or different operating
systems on a single
physical computer machine.
VMware Fusion: This product was designed for Mac users and provides extra
compatibility with all other VMware products and applications.
VMware Player: This product was launched as freeware by VMware for users who
do not have licensed VMWare products. This product is intended only for personal
use.
VMware's software hypervisors intended for servers are
bare-metal embedded hypervisors that can run directly on the server hardware
without the need of an extra primary OS.
The Benefits of VMware
“Virtualization” is the process of installing multiple operating
systems for one or more workstations or servers onto a single physical
workstation or server. This is a very practical solution because the processing
power of the average workstation or server is underused—most systems only use
about 5-15 percent of their processing capabilities. Virtualization is
beneficial for your small business for several reasons:
• It’s cheaper to have several virtualized machines residing on
one physical machine than it is to purchase multiple machines.
• Server room size requirements can be decreased saving you time
and money retrofitting your office space to accommodate a larger server room.
• Save money on the electricity required to power the multiple
machines as well as save on your server room cooling bills.
• Workstation and server
maintenance and upgrades, as well as machine replacement, are cheaper when you
only have to worry about one physical workstation or server.
• Less hardware to manage means less software to upgrade.
VMware’s line of server software includes:
VMware ESX Server: This is an enterprise-level solution, which is built to provide
better functionality in comparison to the freeware VMware Server
resulting from a
lesser system overhead. VMware ESX is integrated with VMware vCenter
that
provides additional solutions to improve the manageability and
consistency of the
server implementation.
VMware ESXi Server: This server is like the ESX Server except that the service the console is replaced with BusyBox installation and it requires very low disk
space to
operate.
VMware Server: Freeware software that can be used over existing operating
systems like Linux or Microsoft Windows.
Virtualization in VmWare
The process of creating virtual versions of physical components
ie Servers, Storage Devices, Network Devices on a physical host is called
virtualization.
Virtualization lets you run multiple virtual machines on a single physical machine which is called ESXi host.
Main components of vCenter Server Architecture:
There are three main components of vCenter Server architecture.
vSphere Client and Web Client: This is a user interface.
vCenter Server database: SQL server or
embedded PostgreSQL to store inventory, security roles, resource pools, etc.
SSO: a
security domain in virtual environment
Different types of Virtualization
There are 5 basic types of virtualization
Server virtualization: consolidates the physical server and multiple OS can be run on a
single server.
Network Virtualization: Provides complete reproduction of physical network into
a software-defined network.
Storage Virtualization: Provides an abstraction layer for physical storage
resources to manage and optimize in virtual deployment.
Application Virtualization: increased mobility of applications and allows
migration of VMs from the host to another with minimal downtime.
Desktop Virtualization: virtualize desktop to reduce cost and increase service.
VmKernel and its importance
VMkernel is a virtualization interface between a Virtual Machine
and the ESXi host which stores VMs.
It is responsible to allocate all available resources of ESXi
host to VMs such as memory, CPU, storage, etc.
It also controls special services such as vMotion, Fault
tolerance, NFS, traffic management and iSCSI.
To access these services, VMkernel port can be configured on
ESXi server using a
standard or distributed vSwitch. Without VMkernel, hosted VMs
cannot communicate with the ESXi server.
Hypervisor and its Types
The hypervisor is a virtualization layer that enables multiple
operating systems to share a single hardware host.
Each operating system or VM is allocated physical resources such
as memory, CPU, storage, etc by the host. There are two types of hypervisors
Hosted hypervisor (works as application i-e VMware Workstation)
Bare-metal (is virtualization software i-e VMvisor, hyper-V
which is installed directly
onto the hardware and controls all physical resources).
Disk types are in VMware
There are three disk types in vSphere.
1. Thick Provisioned Lazy Zeroes: every virtual disk is
created by default in this disk format. Physical space is allocated to a VM
when the virtual disk is created. It can’t be converted to a thin disk.
2. Thick Provision Eager Zeroes: this disk type is used
in VMware Fault Tolerance. All required disk space is allocated to a VM at the time
of creation. It takes more time to
create a virtual disk compare to other disk formats.
3. Thin provision: It provides an on-demand allocation of
disk space to a VM. When data size grows, the size of disk will grow. Storage
capacity utilization can be up to 100% with thin provisioning.
