AWS CloudFormation
AWS CloudFormation
In the simplest way, if we define AWS CloudFormation, it is a freeware tool by Amazon Web Services (AWS) which is needed to manage the infrastructure for a software application to handle AWS. Cloud Formation’s unique feature is that it designs the infrastructure as you want it to be like.
Why do we need AWS CloudFormation?
When the number of infrastructure services and products is doubled due to the necessity, what happens is that AWS cannot handle all at the same time. This is when AWS CloudFormation comes in use.
It is actually infrastructure as code, which can create a seamless clone of the server configuration at any time that will ease the problems faced by the AWS.
With AWS CloudFormation, the configuration changes can be made dynamically as well as embedded into the existing environment without any obstruction.
Managing multiple AWS resources is a tedious task as well as quite time-consuming. In the absence of AWS CloudFormation, the developers focus their attention and time on building the infrastructure and the services and focus less on the application development as such.
Rebuilding any infrastructure product or services is all the more strenuous and challenging. Even deploying the existing environment is also a cumbersome task, as everything has to be started from scratch.
Now, this is where AWS CloudFormation comes as the saviour.
What is AWS CloudFormation?
AWS CloudFormation is the simplest way to manage the AWS infrastructure resources by assisting in simple modeling and setting up with ease in an orderly manner. It is easier to build a CloudFormation using a template design which can be designed with respect to user preference.
Like for example, a template can be defined as what the application requires like an Amazon Elastic Compute Cloud (EC2) instance.
The major advantage is that the user needs not asses the dependencies or complexities of the infrastructure services that are uploaded to the CloudFormation portal, with that of the application running on top. Once the template is designed, it is vetted and validated, the CloudFormation analyses and contemplate the resources users define.
Hence it nullifies the manual dependency and does validation which can easily facilitate the focus on the core business.
When we learn about CloudFormation, we have two important aspects to learn – A template and a Stack. Together they complement each other.
What is AWS CloudFormation Template?
A template is a simple text file that contains the declaration either in JavaScript Object Notation (JSON) or in a YAML Standard which can be edited using a normal text editor or even a CloudFormation editor. These templates can be managed in the source control system.
In the template, one can define the AWS resources that are needed to be created or configured. The template must contain the resources and the resource properties to be connected with, using input parameters. The template can be saved as text files with extensions .yaml ,.json , .txt or even .template . These are the blueprints for creating the AWS resources and are portable too.
The template contains 9 major objects :
Format Version:
Helps to identify the capability of the template.
Description:
Arbitrary comment about the template can be included like purpose etc.
Meta Data:
Details of the resources in the template. It holds the implementation details.
Parameters:
Helps to input custom dynamic value inputs to the template. Enables to customize templates.
Mapping:
Helps to match a key to the corresponding value.
Conditions:
An optional one, where statements can be included based on conditions, where the inputs become the result of the conditional statement.
Transform:
An optional one defines one or more transforms to be used in the template. It is in the simple declarative AWS CloudFormation format.
Resources:
Declares the resources that are used in the template.
Outputs:
An optional one, to declare the output to show on the console or to be reused in another template.
What are AWS CloudFormation Stacks?
In AWS CloudFormation multiple related resources are managed in a single unit called Stack. One can delete, create and update a resource in a stack. These stacks are clearly defined by the stack’s template in AWS CloudFormation.
These stacks can be embedded and updated in the template any time, which can be again included by the user dynamically during run time in the resource and is portable. A stack can include resources database server or a web server that can be used to run an application.
Nested Stack:
There can be nested stacks, using CloudFormation with a clearly defined hierarchy.
Windows Stack:
This gives the opportunity to configure and update the stack in windows instances. AWS has few predefined stacks for Windows stacks.
What is the Cloud Formation Access Control?
IAM
Ensures that IAM users only get access. Only they can do operations like create, update and delete.
Service Role:
Facilitates AWS CloudFormation to call the resources in a stack on behalf of the user.
Stack Policy:
Applicable to all users who want to update the stack. One cannot include different users with varied stack policies here.
How does AWS CloudFormation work?
- One can build a template based on various requirements and saved in the system.
- Using the AWS CloudFormation create a stack on the template defined.
- AWS CloudFormation then, diagnoses the template design and the configuration to verify the template on dependencies and validate as well as analyse before provisioning the template for the resource.
Benefits of AWS CloudFormation
All in One:
One can model all resources in a single text file and can be used invariably anywhere.
Automatable:
The templates are completely reusable which can be built as well as rebuilt any number of times without any scripting.
All it is a Code:
The template is just a code and can be easily maintained and version controlled as per usage.
No Extra Charges:
As AWS CloudFormation comes along with the AWS Resources, no extra charges have to be paid.
Conclusion
AWS CloudFormation is a powerful tool which simply automates the infrastructure making it easy to use. Currently, many popular companies are using AWS CloudFormation to deploy as well as manage their resources. AWS CloudFormation has a steep learning curve, which makes it all the more interesting to learn.