AWS Certified Solutions Architect Study Guide. David Higby ClintonЧитать онлайн книгу.
AWS doesn't mean that service disruptions or security breaches will never occur. Drives may stop spinning, major electricity systems may fail, and natural disasters may happen. But when something does go wrong, AWS will provide service credits to reimburse customers for their direct losses whenever uptimes fall below a defined threshold. Of course, that won't help you recover customer confidence or lost business.
The exact percentage of the guarantee will differ according to service. The service level agreement (SLA) rate for AWS EC2, for instance, is set to 99.99 percent—meaning that you can expect your EC2 instances, ECS containers, and EBS storage devices to be available for all but around four minutes of each month.
The important thing to remember is that it's not if things will fail but when. Build your applications to be geographically dispersed and fault tolerant so that when things do break, your users will barely notice.
Working with AWS
Whatever AWS services you choose to run, you'll need a way to manage them all. The browser‐based management console is an excellent way to introduce yourself to a service's features and learn how it will perform in the real world. There are few AWS administration tasks that you can't do from the console, which provides plenty of useful visualizations and helpful documentation. But as you become more familiar with the way things work, and especially as your AWS deployments become more complex, you'll probably find yourself getting more of your serious work done away from the console.
The AWS CLI
The AWS Command Line Interface (CLI) lets you run complex AWS operations from your local command line. Once you get the hang of how it works, you'll discover that it can make things much simpler and more efficient.
As an example, suppose you need to launch a half‐dozen EC2 instances to make up a microservices environment. Each instance is meant to play a separate role and therefore will require a subtly different provisioning process. Clicking through window after window to launch the instances from the console can quickly become tedious and time‐consuming, especially if you find yourself repeating the task every few days. But the whole process can alternatively be incorporated into a simple script that you can run from your local terminal shell or PowerShell interface using the AWS CLI.
Installing and configuring the AWS CLI on Linux, Windows, or macOS machines is not hard at all, but the details might change depending on your platform. For the most up‐to‐date instructions, see docs.aws.amazon.com/cli/latest/userguide/installing.html.
AWS SDKs
If you want to incorporate access to your AWS resources into your application code, you'll need to use an AWS software development kit (SDK) for the language you're working with. AWS currently offers SDKs for nine languages, including Java, .NET, and Python, and a number of mobile SDKs that include Android and iOS. There are also toolkits available for IntelliJ, Visual Studio, and Visual Studio Team Services (VSTS).
You can see a full overview of AWS developer tools at aws.amazon.com/tools.
Technical Support and Online Resources
Things won't always go smoothly for you—on AWS just as everywhere else in your life. Sooner or later, you'll need some kind of technical or account support. There's a variety of types of support, and you should understand what's available.
One of the first things you'll be asked to decide when you create a new AWS account is which support plan you'd like. Your business needs and budget will determine the way you answer this question.
Support Plans
The Basic plan is free with every account and gives you access to customer service, along with documentation, white papers, and the support forum. Customer service covers billing and account support issues.
The Developer plan starts at $29/month and adds access for one account holder to a Cloud Support associate along with limited general guidance and “system impaired” response.
For $100/month (and up), the Business plan will deliver faster guaranteed response times to unlimited users for help with “impaired” systems, personal guidance and troubleshooting, and a support API.
Finally, Enterprise support plans cover all of the other features, plus direct access to AWS solutions architects for operational and design reviews, your own technical account manager, and something called a support concierge. For complex, mission‐critical deployments, those benefits can make a big difference. But they'll cost you at least $15,000 each month.
You can read more about AWS support plans at aws.amazon.com/premiumsupport/compare-plans.
Other Support Resources
There's plenty of self‐serve support available outside of the official support plans:
AWS community help forums are open to anyone with a valid AWS account (forums.aws.amazon.com).
Extensive and well‐maintained AWS documentation is available at aws.amazon.com/documentation.
The AWS Well‐Architected page (aws.amazon.com/architecture/well-architected) is a hub that links to some valuable white papers and documentation addressing best practices for cloud deployment design.
There are also plenty of third‐party companies offering commercial support for your AWS deployments.
Summary
Cloud computing is built on the ability to efficiently divide physical resources into smaller but flexible virtual units. Those units can be “rented” by businesses on a pay‐as‐you‐go basis and used to satisfy just about any networked application and/or workflow's needs in an affordable, scalable, and elastic way.
Amazon Web Services provides reliable and secure resources that are replicated and globally distributed across a growing number of regions and availability zones. AWS infrastructure is designed to be compliant with best‐practice and regulatory standards—although the Shared Responsibility Model leaves you in charge of what you place within the cloud.
The growing family of AWS services covers just about any digital needs you can imagine, with core services addressing compute, networking, database, storage, security, and application management and integration needs.
You manage your AWS resources from the management console, with the AWS CLI, or through code generated using an AWS SDK.
Technical and account support is available through support plans and through documentation and help forums. AWS also makes white papers and user and developer guides available for free as Kindle books. You can access them at this address:
www.amazon.com/default/e/B007R6MVQ6/ref=dp_byline_cont_ebooks_1?redirectedFromKindleDbs=true
Exam Essentials
Understand AWS platform architecture. AWS divides its servers and storage devices into globally distributed regions and, within regions, into availability zones. These divisions permit replication to enhance availability but also permit process and resource isolation for security and compliance purposes. You should design your own deployments in ways that take advantage of those features.
Understand how to use AWS administration tools. Though you will use your browser to access the AWS administration console at least from time to time, most of your serious work will probably happen through the AWS CLI and, from within your application