Windows azure 101

There are too many clouds in the industry, each of which is very distinctive! For Microsoft, Windows Azure is the core of its cloud strategy. I have always had a vague impression on it, David Chappell's article-introducing
Windows azure-a detailed introduction to the basic knowledge and features of Windows azure helps clarify some previous misunderstandings. For example, Windows azure has always been regarded as a PAAs platform, but with the introduction of Windows azure virtual machines, azure now supports IAAs. This is a good introduction. We recommend it to you here!

It is a classification of the main modules of Windows azure. It provides a powerful picture and is helpful for you to grasp azure as a whole. More accurately, for Azure, its components all exist in the form of services.

 

Execution model)

One of the most basic functions of the cloud platform is to be able to run programs. Azure provides three ways to run applications: virtual machines, websites, and cloud services. The three methods have their own characteristics: the virtual machine provides a general-purpose computing environment, and the website provides low-cost website hosting; cloud services are the best choice for creating scalable, reliable, and low-management applications. Based on actual needs, they can be used separately or mixed.

 

(1) Virtual Machine: named 'windows azure Virtual Machine ', which provides IAAs (basic architecture as a service ). This method allows users to create virtual machines using standard vhd or their own vhd as needed, and pay for the virtual machines based on the number of hours used. Windows azure virtual machine provides a set of standard vhd, including Microsoft's Windows Server 2012, Windows Server
2008 R2, Windows Server 2008 R2 (with SQL Server), and Linux provided by Microsoft's partners. At the same time, users can upload their own vhd for free. You can save the currently running Vm, create a new virtual machine with the saved vhd, or copy the vhd from Windows azure to the Local Machine for running.

 

(2) Website: Windows azure supports running websites and web applications. Virtual machines actually support websites and web applications, but you need to manage related virtual machines on your own. The Windows azure website provides a managed web environment through IIS. Without any modification, you can directly migrate your website to the Windows azure website, or create a new website on the cloud. Once a website is created, you can dynamically add and delete website instances, and load balancing between instances depends on the website itself.
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(3) cloud service: it truly embodies the true meaning of paas (platform as a service, platform as a service) and is used to implement scalable, highly reliable, and low management cost applications. You can use C #, Java, PHP, Python, node. JS, or other technologies to implement such applications. These applications run on a Windows Server Virtual Machine. The virtual machine here is different from the virtual machine in the Windows azure virtual machine execution mode. The main difference is that the virtual machine here is
Managed by Azure, including installing system patches and automatically creating vhd installed patches. At the same time, Windows Azure is responsible for monitoring these virtual machines at all times and restarting those crashed machines. There are two types of virtual machines: Web role (with IIS installed) and work role (with IIS installed ). The billing method is the same as that for Windows azure virtual machines.

 

Data Management)

If there is an application, there must be data. Different types of applications require data support. To this end, Windows azure provides multiple ways to store and manage data. If you are using a Windows azure virtual machine, you can choose to run your own database management system (SQL or nosql), but at the same time you have to manage the database. Windows azure provides three data solutions that greatly simplify database management. SQL database is used to meet the needs of relational databases. Tables is used to quickly access a large amount of simple structured data, while blobs is used for unstructured binary storage. These types of data are replicated three copies on different machines of the same data to achieve high availability. Windows
Azure data services are charged based on usage, including gigabyte/monthly billing method.

(1) SQL database: a relational database provided by Windows Azure, also known as SQL azure. Supports most relational database features. for developers familiar with SQL Server or other relational databases, the use of SQL database is similar. SQL database is not only a DBMS on the cloud, but also a PAAs service. You can still control your data and manage access permissions, SQL database
It helps you complete other management tasks, including software and system upgrades, data distribution to multiple machines for load balancing, etc. In addition, not only Windows azure applications can use the SQL database service, but also client systems outside the cloud (desktop systems, mobile phones, laptops, etc.) can use this service. At the same time, the high availability features achieved through replication also greatly reduce the downtime of SQL database ). (2) tables: If your windows azure application needs to quickly access a large amount of data types without complex SQL queries, Windows azure tables is most suitable for this scenario. It is especially suitable for scenarios where only storage and simple query are required. The table name is easy to misunderstand because of the relational table structure, which is actually the key/value storage of nosql. Quick access to data is supported, but complex operations such as join are not supported. Table has good scalability. A single table can store up to terabyte data. Because of its simple implementation, table prices are cheaper than SQL.
Database.