Azure Fundamentals (1) | What is Azure?

What is cloud computing?

Cloud computing is the delivery of computing services over the internet, which is otherwise known as the cloud. These services include servers, storage, databases, networking, software, analytics, and intelligence. To put it another way, cloud computing is a way to rent compute power and storage from someone else's datacenter. Cloud computing offers faster innovation, flexible resources, and economies of scale.

Why is cloud computing typically cheaper to use? by using a pay-as-you-go pricing model.

Instead of maintaining CPUs and storage in your datacenter, you rent them for the time that you need them. The cloud provider takes care of maintaining the underlying infrastructure for you. 

Cloud provides on-demand access to:
- A nearly limitless pool of raw compute, storage, and networking components.
- Speech recognition and other cognitive services that help make your application stand out from the crowd.
- Analytics services that deliver telemetry data from your software and devices.

 

https://docs.microsoft.com/en-us/learn/modules/intro-to-azure-fundamentals/what-is-cloud-computing

What is cloud computing? - Learn

 

 

 

What is Azure?

Azure is a continually expanding set of cloud services.

What is the Azure portal?
The Azure portal is a web-based, unified console that provides an alternative to command-line tools. With the Azure portal, you can manage your Azure subscription by using a graphical user interface. Azure provides more than 100 services that enable you to do everything from running your existing applications on virtual machines, to exploring new software paradigms, such as intelligent bots and mixed reality.

 

You can:
- Build, manage, and monitor everything from simple web apps to complex cloud deployments.
- Create custom dashboards for an organized view of resources.
- Configure accessibility options for an optimal experience.

What is Azure Marketplace?
Azure Marketplace helps connect users with Microsoft partners, independent software vendors, and startups that are offering their solutions and services, which are optimized to run on Azure. Azure Marketplace customers can find, try, purchase, and provision applications and services from hundreds of leading service providers. All solutions and services are certified to run on Azure. (...) Using Azure Marketplace, you can provision end-to-end solutions quickly and reliably, hosted in your own Azure environment. At the time of writing, there are more than 8,000 listings.

https://docs.microsoft.com/en-us/learn/modules/intro-to-azure-fundamentals/what-is-microsoft-azure

What is Azure? - Learn

 

 

 

How does Azure work?

Azure, like other cloud platforms, relies on a technology known as virtualization. Most computer hardware can be emulated in software. Computer hardware is simply a set of instructions, which are permanently, or semi permanently, encoded in silicon. Emulation layers are used to map software instructions to hardware instructions. Emulation layers allow virtualized hardware to execute in software like the actual hardware itself. 

Essentially, the cloud is a set of physical servers in one or more datacenters. The datacenters execute virtualized har ware for customers. So how does the cloud create, start, stop, and delete millions of instances of virtualized hardware for millions of customers simultaneously? 

To understand the servers, let's look at the architecture of hardware in the datacenter. Inside each datacenter, there's a collection of servers sitting in server racks. Each server rack contains many server blades, and a network switch. These provide network connectivity and a power distribution unit (PDU), which creates power. Racks are sometims grouped together in larger units known as clusters. 

The server racks, or clusters, are chosen to run virtualized hardware instances for the user. However, some servers run cloud management software, known as a fabric controller. The fabric controller is a distributed application with many responsibilities. It allocates services, monitors the health of the server and the services running on it, and heals servers when they fail. 

Each instance of the fabric controller is connected to another set of servers running cloud orchestration software, typically known as the front end. The front end hosts the web services, RESTful APIs, and internal Azure databases, which are used for all functions in the cloud. 

For example, the front end hosts the services that handle customer requests. The requests allocate Azure resources and services such as virtual machines, and Azure Cosmos DB. First, the front end validates and verifies if the user is authorized to allocate the requested resources. If so, the front end checks a database to locate a server rack with sufficient capacity, which instructs the fabric controller to allocate the resource. 

Azure is a huge collection of servers and networking hardware, which runs a complex set of distributed applications. These applications orchestrate the configuration and operation of virtualized hardware and software on those servers. The orchestration of these servers is what makes Azure so powerful. With Azure, users don't have to maintain and upgrade their hardware as Azure does this behind the scenes. 

 

https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/get-started/what-is-azure

How does Azure work? - Cloud Adoption Framework

 

https://docs.microsoft.com

 

1. Azure Portal

It is one way of accessing the Azure API in a well structured, self-explaining way. At least that’s what I experienced when I used this Graphical User Interface in a project. Besides using a Web Application there exist other ways of using the Azure API. For example, the Azure CLI. It is a Command Line Interface and might be more complicated to use for someone who never uses CLI’s. But has the advantage of automation. 

 

2. Azure API
API stands for Application Programming Interface and is a way to expose a common set of operations that can be consumed by different User Interfaces or other parts of a system. In this case, the Azure Portal and the Azure CLI are both abstractions of the same application. 

 

3. Orchestrator
It is a central service that is responsible for managing everything that goes on in Azure including handling User Requests.  Our little investigation recently gives a hint that there is an Event Hub that is part of the orchestrator. The orchestrator is connected to Fabric Controllers. As depicted in the overview. (...) My guess is that a resource group will also run on a virtual machine. That means when I created the group, the orchestrator told a fabric controller to create a new virtual machine on one of the servers.  

 

4. Network Switch
Allows networked devices to communicate with each other. The Fabric Controller needs to be able to talk to every server on his rack. Well they are all connected via a network switch. Btw, there are managed and unmanaged switches. I am pretty sure that Azure uses managed switches because they need greater controll over the network traffic and access. 

 

5. Fabric Controller
It is a distributed program that runs on one server on each rack in the Azure datacenters. Its main task is to create and assign the appropriate Virtual Machines based on the users’ needs. 

 

6. Virtual Machine
It makes use of a technology called Virtualization to separate the hardware of a computer from its operating system. Let’s say you have a Windows machine and you want to run Mac OS on it. To do so your Windows machine needs to emulate all the hardware that is needed to run Mac OS. It does that by running an abstraction layer called Hypervisor. 

 

https://medium.com/@alan.meile/how-does-azure-cloud-work-7479b6f12979

How does Azure Cloud work?