User:NikaSaumi/My sandbox

Virtualization


To understand how Cloud works you should first learn something about virtualization. The possibility of virtualization is a revolution in IT. For example it is an advance for big companies. Before virtualization they had to own a great deal of physical computers - hardwares. Nowadays we can create multiple virtual machines (or VMs) using just one physical computer. Why is it such an advantage? For start, each of these virtual machines acts like a computer file - you can easily copy it and with one click create an identical software with everything in it. That saves companies a lot of time as they do not have to set each and every (physical) computer individually. Another advantage is that the virtual machines "do not know" that they are virtual, they act just like the physical ones which helps with security as the hackers cannot get to the hardware.

Cloud
Cloud could not work without virtualization. There are several companies that offer physical machines (such as Windows, Apple). "Above" these harwares there is a virtual layer - Cloud openstack. Another layer, VM ware, gives the customers virtual machines. Easily said - cloud offers virtual machines, they only have to make sure that they have enough physical computers to make the virtual ones. The only problem with Cloud is that it is slower (than a Hardware) when it is processing a request (as it has to go through all the layers).

Gitlab
Is a server where all the work that has been done by developers is. It administers the work of developers. This proceeds automatically. Gitlab communicates with Jenkins.

Jenkins
Jenkins knows about every change that has been made. With every change it automatically starts up a test. Thanks to Jenkins the programmer knows in about 30 sec. if he made a mistake or not. This saves a lot of time.