What Is A Cloud | SysAdminXpert

The very popular question of what is a cloud that everyone talking and why it is such a big deal.

Defining what is a cloud?

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We’ve been “virtualizing” for 40+ years… why all the hype now? What’s new?

“The Cloud” is using virtualization and automation to provide users with self-service computing products that provide infinite scale at low cost.

If we just break down into two pieces as follow:

The Cloud is:

Virtualization
Automation

Virtual just means “not physical”

CPU, Disk, RAM, Network Cards are “virtualized” so that they can be used by many “virtual” computers resident on the machine
The software is “Virtualized” so you don’t have/need your own copy of it, and many users “share” it
Virtual Hardware and Software is very easy to spin up/takedown

In the above simple diagram you can see downside it is an actual machine which contains CPU, Memory, Network Card and disk. We talk about how virtualization works, we have plugin hypervisor so that we can chop/share same hardware resource with all Virtual machines(VM’s), here we have created 3 VM’s on one physical machine, each of the users who are using these VM’s appears physical machine. You can log in to these VM’s and you see a small subset of those resources, this is what virtualization.

We’ve been “virtualizing” for 40+ years… why all the hype now? What’s new?

Hardware Virtualization just started in the late 1990s
Broadband and Mobile driving “Web Scale”
Hardware speeds and capacity
Public cloud offerings from Amazon EC2 / Rackspace Cloud
The whole “Saas” crowd… Salesforce, Google Apps eating competitors lunch
Economy

Automation provides:

Self Service
(Near) Infinite Scale
Utility-Based Pricing and Service

Cloud Types:

Public: is like what Amazon offers – Low-Cost, “Leased”, Virtual Servers, Infinite Scale, and Utility-based pricing and service

Private: is your own hardware, in-house with limited scale and fixed monthly cost with total control in another way we can define as “setup own cloud for internal users”

Hybrid: Combination of both public and private cloud:

control where you need
scale when you need

leverage to public cloud resources perhaps to boost capacity and I still leverage my internal fixed cost and total control private cloud. This quick tour of these various areas gives you a good overall definition of what is a cloud.