Scaling is one of the most important factors for Cloud Services. It allows the user to optimize the cost by providing resources only when required. Amazon Cloud Auto Scaling provides horizontal scaling by automatically adding or removing the computer resources for the application hosted on AWS. The changes are on demand based on the triggers configured by the user.

Consider the following scenario: when the user’s web application is hosted on AWS and there is a sudden increase of traffic to that website. If the user fails to scale up based on the need, the application may fail or give a slow response. If the user has configured parameters such that AWS adds more application resources (EC2 Instances) when the traffic increases the application will continue to respond with the same performance as before.

The present guide demonstrates how to install Auto Scaling CLI on a Windows machine.

AWS Auto Scaling is ideally suited for the application which has varying traffic needs based on the hours (e.g. 9 AM to 5 PM) or events (e.g. promotional period). Auto Scaling allows the user to scale resources dynamically (based on conditions, such as an increase in the CPU performance, Memory, Disk usage, etc) or at a pre-defined frequency (every Sunday 12 AM, every Monday 9 AM, etc).

AWS does not provide the AWS Management console for Auto Scaling. All the operations should be performed through CLI or API.

This is distributed in three parts, where the first part demonstrates how to download CLI. The second part demonstrates how to install and setup Java. Lastly, the third part demonstrates how to setup the AWS environment.

A) Downloading CLI from AWS S3

1. Create a folder to store the APIs in the local drive. E.g. C:\AWS\autoScaling

2. Download the Amazon AWS Auto Scaling API tools for the Windows (.zip) file and save in the folder created in step#1.

3. Unzip the file and extract it to a local drive.

Install and setup Java

a. If JDK / JRE is not installed and the environment variables are not set, please follow the below mentioned steps or else skip to section ‘C’.

b. Install and download JDK 5 or an above version. The JDK download is free and JDK 7 is available for download at http://www.oracle.com/technetwork/java/javase/downloads/index.html.

c. Set the environment variable as following:

i. JAVA_HOME=<JRE / JDK PATH>

ii. PATH=%PATH%;<JAVA_HOME>\bin\; C:\AWS\autoscaling\AutoScaling-1.0.61.2\bin\;

iii. CLASSPATH=%PATH%;<JAVA_HOME>\lib\; C:\AWS\autoscaling\AutoScaling-1.0.61.2\lib\

Note that the bin folder of Auto Scaling API has been added as a part of PATH so that the user can also run the Auto Scaling commands outside of the Auto Scaling folder.

4. Run the command java –version and check if it displays the correct version of JDK / JRE.

5. If the above mentioned commands are setup through the command window, it will only be valid for the session of the command window.

6. Please setup all the above mentioned parameters through the Environment Variables. The user can access the Environment variables for Windows 7 / Vista through: MyComputer -> Right Click and Select Properties. -> Select “Advanced System Settings” from the left menu and go to Environment variables.

For Windows XP Right Click on Computer -> Select Properties -> Select Advanced Tab and click -> Environment variables.

7. Setup all the above mentioned variables, as shown below:

B) Download and setup the AWS Certificate File and Private Keys. (Some of the data is masked or removed in the screen for the purpose of confidentiality.)

1. Go to the AWS Account section: http://aws.amazon.com/account

2. Click on “Security Credentials” in the left menu, as shown below:

3. Click on “Access Credentials” and select the “X.509 Certificates” tab.

4. It will display all the existing Active / Inactive certificates.

5. Click on “Create a new Certificate”, which will display the following screen: