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IN THIS CHAPTER

❯❯ Considering the limits of the free services of AWS

❯❯ Knowing what hardware you need to work with AWS

❯❯ Obtaining your AWS developer account

❯❯ Checking your setup

As a developer, you need some knowledge of administration tasks on Amazon Web Services (AWS) before you can do much else. The reason is that you need to set up and configure some test scenarios to work with when performing development tasks. Obviously, you don’t want to ruin a perfectly good production setup by using untested code. Discovering how AWS works is much easier if you have your own account and resources to work with. Of course, you don’t want to have to pay for the learning time, which is why the first section of this chapter discusses the free services that AWS has to offer, and there are a lot of them. Unfortunately, free resources don’t always remain free, and sometimes free is an illusion, so the chapter discusses these issues as well.

Development also means having some amount of hardware available for the task. In this case, you actually need several levels of hardware:

❯❯ User: To even start working with your computer, you have basic user needs to meet. This chapter assumes that you have the hardware required to run the user environment for your system. Because you could end up simulating more than one user, you may want to ensure that your system well exceeds the requirements for a single user, even when you plan to perform simulations through task switching (placing one user in hibernation while you act as another).

❯❯ Network: You require a connection to the Internet and any local network resources needed to develop your application. This chapter doesn’t cover any of these requirements. However, given that you plan to perform development tasks over the network, you may need to talk with your network administrator to ensure that you have proper rights and any additional hardware required to allow the bandwidth required to work with AWS.

❯❯ Development: The programming language you choose will have certain hardware requirements, as will any developer add-ons you require. This chapter assumes that you know what these requirements are for your particular setup. You must plan this hardware in addition to any other hardware required for other purposes.

❯❯ AWS: Interestingly enough, your AWS setup also requires hardware. This chapter discusses the hardware you typically want to have to ensure that AWS works properly. This hardware is in addition to the hardware you need to run your user, networking, and development environment.

To work as an AWS developer, you actually need two levels of AWS access. The first level of access provides an account that you use to set up and configure services such as Amazon Simple Storage Service (S3). The second level of access is your developer account, which includes obtaining a development key that you use to access AWS through code. This chapter helps you obtain both levels of access.

The final section of the chapter helps you test your setup. You perform the same tasks that you perform when developing an application, but a short version of them. In this case, you perform a quick S3 setup, test it, and then access it using scripted code. The idea is to ensure that you actually can access AWS as you work through the examples later in the book.

Discovering the Limits of Free Services

Amazon does provide the means for using many of its cloud services for free. In fact, you can see some of these services at http://aws.amazon.com/free/. However, as you look through the list of services, you see that some expire but others don’t. In addition, some have limits and others don’t. Those that do have limits don’t have the same limits, so you need to watch usage carefully. It’s really quite confusing. The following sections help clarify what Amazon actually means by saying some services are free.

Expiring services versus non-expiring services

Many of the AWS services you obtain through the free tier have expiration dates, and you need to consider this limitation when evaluating and possibly using the service to perform useful work. Figure 2-1 shows examples of services with an expiration date. Notice that you must begin paying for the service 12 months after you begin using it.

FIGURE 2-1: Some services have an expiration date when you must begin paying for it.

In some cases, the product itself doesn’t have an expiration date, but the service on which it runs does. For example, when viewing the terms for using the free software, the software itself is indeed free. However, to run the software, you must have the required service, which does come with an expiration date (see Figure 2-2). In this case, the Amazon Mobile Analytics depend on Amazon S3 (listed near the bottom of the description). You have access to 100 million events per month free, but in order to export your event data, you need S3, which has an expiration date. Notice also that after you reach the 100 million events level, you must pay an additional amount for each additional million events, so free doesn’t necessarily remain free.

FIGURE 2-2: Software may be free, but the service on which it runs might not be.

You also have access to some products that are both free and have no expiration date. These nonexpiring offers still have limitations (and often caveats), but you don’t have to worry about using those products within the limits for however long you want (or until Amazon changes the terms). Figure 2-3 shows an example of this kind of service. Notice that the service is free, doesn’t expire, and doesn’t depend on a service that expires. However, you must pay for both throughput and storage, so a cost is still involved.

FIGURE 2-3: A few services don’t come with expiration dates.

Knowing the terms under which you use a service is essential. The free period for services with an expiration date goes all too quickly, and you may suddenly find yourself paying for something that you thought remained free for a longer time frame. Given that Amazon can change the terms of usage at any time, you need to keep checking the terms of service for the services that you use. A service that lacks an expiration date today may have an expiration date tomorrow.

ABOUT THE GRAPHICS IN THE BOOK

The material in this book works on several different platforms, including Windows, Linux, and Mac OS X. However, presenting screenshots of every platform you can use with AWS isn’t practical because the book would end up being filled with pictures rather than content. For this reason, the screenshots you see in the book are from a Windows 7 system using the Firefox browser, where appropriate. Depending on the operating system, browser, and other software you use, you may not see precisely the same screenshots on your system. In looking at the graphics, you should compare content rather than precise appearance. Any differences in appearance are normal, and you don’t need to worry about them.

Considering the usage limits

Look again at Figures 2-1 through 2-3. Note that all these products have some sort of usage limit attached to them – even the free software – because of the software’s reliance on an underlying service. (Some software relies on more than one service, so you must also consider this need.) For example, you can use Amazon Elastic Compute Cloud (EC2) for 750 hours per month as either a Linux or Windows setup. A 31-day month contains 744 hours, so you really don’t have much leeway if you want to use the EC2 service continuously.