AWS CloudFormation Template Tutorial

Summary

This tutorial demonstrates the process of using AWS CloudFormation to create, update, and delete cloud resources. It begins with the creation of an EC2 instance and an Elastic IP, followed by the addition of security groups. The script illustrates how CloudFormation templates are updated to reflect changes, and how the service manages resource lifecycle, including automatic cleanup. The video concludes with a demonstration of deleting a stack, showcasing CloudFormation's efficiency in resource management.

Takeaways

• 🚀 The script provides a hands-on example of using AWS CloudFormation to create an EC2 instance, an Elastic IP, and two security groups.
• 📚 The focus is on understanding the process of creating and updating CloudFormation templates rather than the syntax or content of the template itself.
• 📍 It's important to work in the AWS North Virginia region (USEast1) to ensure consistency with the course setup.
• 📂 The script demonstrates how to upload a CloudFormation template to Amazon S3 and create a stack from that template.
• 🔖 Tags are used in CloudFormation to categorize and manage resources, with the example showing a 'course' tag with 'CloudFormation' as its value.
• 🔄 CloudFormation templates can be updated by uploading a new template, which triggers changes to the stack, including resource creation and updates.
• 🛠️ The script shows that adding certain resources to a template can result in the replacement of existing resources, such as when adding security groups to an EC2 instance.
• 🔍 CloudFormation provides a preview of changes before updating a stack, allowing users to review what will be created, updated, or deleted.
• 🗑️ Deleting a CloudFormation stack automatically cleans up all resources associated with that stack, simplifying the management process.
• 🔑 The script highlights the importance of managing resources through CloudFormation for consistency, control, and ease of maintenance.
• 🔍 The script emphasizes the visibility provided by CloudFormation's event logs, which track the creation, update, and deletion of resources.

Q & A

What is an EC2 instance in AWS?

An EC2 instance is a virtual server in the cloud that users can launch and manage in the Amazon Web Services (AWS) cloud. It is a fundamental part of the AWS infrastructure that allows users to run applications on virtual servers in the AWS cloud.

What is an Elastic IP and why is it used in AWS?

An Elastic IP is a static IP address designed for dynamic cloud computing, designed to be associated with an EC2 instance in a VPC. It is used to maintain a consistent IP address even when the underlying instance changes, which is useful for maintaining a persistent connection to an application.

What are security groups in AWS and what role do they play?

Security groups act as a virtual firewall for instances to control inbound and outbound traffic. They are used to allow or deny network access to instances based on IP addresses, protocols, and ports.

What is CloudFormation and how does it simplify infrastructure management?

AWS CloudFormation provides a common language for you to describe and provision all the infrastructure resources in your cloud environment. It simplifies the management of related resources as a stack, making it easier to manage and update the infrastructure as a whole.

Why is it important to work in the US East (N. Virginia) region for this course?

The instructor wants all participants to have the exact same setup as them to ensure consistency and avoid confusion. This standardization helps in following along with the course without encountering region-specific differences.

What is the purpose of tags in CloudFormation?

Tags in CloudFormation are used to organize and categorize resources within a stack. They can be used to filter resources and provide additional metadata about the resources that are created.

How does CloudFormation handle updates to a stack?

CloudFormation updates a stack by deploying changes to the resources defined in the new template. It can create new resources, update existing ones, and even replace resources if necessary, while ensuring that the overall stack remains functional.

What happens when a CloudFormation stack is updated with a new template?

When a stack is updated, CloudFormation compares the new template with the current state of the stack and determines the changes needed. It then applies these changes, which may include creating new resources, modifying existing ones, or replacing them entirely.

How does CloudFormation manage resource dependencies during updates?

CloudFormation understands the dependencies between resources and updates them in the correct order. For example, it may create security groups before an EC2 instance to ensure that the instance can be properly configured with the groups.

What is the process for deleting resources created by CloudFormation?

To delete resources created by CloudFormation, you can use the 'Delete Stack' option in the CloudFormation console. This will initiate the deletion of all resources associated with the stack in the correct order, ensuring a clean removal of the infrastructure.

Outlines

00:00

🚀 Introduction to AWS CloudFormation

The video script begins with an introduction to AWS CloudFormation, focusing on creating a simple EC2 instance, which is a fundamental server offering in AWS. The presenter guides the audience to set aside concerns about code syntax and instead concentrate on the process of creating a CloudFormation template. The script emphasizes the importance of having the same setup as the presenter, particularly the use of the North Virginia (US East) region in AWS. The audience is instructed to navigate to the CloudFormation service and create a new stack using an uploaded template, which in this case, is a basic EC2 instance template. The presenter also explains the process of uploading the template to Amazon S3, validating it, and initiating the creation of the stack.

05:02

🛠️ Exploring CloudFormation Stack Resources and Tags

In this section, the script delves into the resources created by the CloudFormation stack, specifically highlighting the creation of an EC2 instance with tags that include a course identifier and CloudFormation-specific tags such as the logical ID, stack ID, and stack name. The presenter demonstrates how to access the EC2 management console to view the instance and its tags, emphasizing the automatic application of tags specified in the CloudFormation template. The script then discusses the need to update the stack to include additional resources, such as security groups and an elastic IP, which requires uploading a new CloudFormation template and reviewing the changes before updating the stack.

10:03

🔄 Updating and Managing CloudFormation Stacks

The script continues with a detailed explanation of how to update an existing CloudFormation stack by uploading a new template that includes modifications such as additional security groups and an elastic IP. The presenter clarifies that CloudFormation templates cannot be edited directly but must be replaced with updated versions. The audience is shown how to review the changes that will occur, including the addition of resources and the replacement of the EC2 instance due to the security group update. The script also covers the automatic cleanup performed by CloudFormation, such as terminating the old EC2 instance once the new one is up and running. Finally, the presenter discusses the process of deleting a CloudFormation stack, which cleans up all associated resources in the correct order, demonstrating the ease and efficiency of managing cloud resources through CloudFormation.

Keywords

💡CloudFormation

CloudFormation is a service offered by Amazon Web Services (AWS) that allows users to create and manage a collection of related AWS resources using a template file. In the video, it is the primary tool used to demonstrate the creation, update, and deletion of AWS resources such as EC2 instances, security groups, and Elastic IPs. The script mentions CloudFormation as the central theme, showing how it can be used to automate the provisioning of AWS resources.

💡EC2 Instance

An EC2 (Elastic Compute Cloud) Instance is a virtual server in the AWS cloud. It is a fundamental concept in the video, where the script describes the process of creating an EC2 instance using CloudFormation. The EC2 instance is part of the AWS free tier, and it is used to demonstrate the automation capabilities of CloudFormation.

💡Elastic IP

An Elastic IP is a static IP address designed to be attached to an AWS EC2 instance to maintain a consistent IP for the instance, even if it is stopped and started again. In the video, the script explains how to add an Elastic IP to an EC2 instance using CloudFormation, enhancing the instance's accessibility and reliability.

💡Security Groups

Security groups in AWS are a virtual firewall that controls inbound and outbound traffic to EC2 instances. The script discusses the creation of two security groups and their association with an EC2 instance. This demonstrates the ability of CloudFormation to handle complex configurations that ensure the security and accessibility of AWS resources.

💡Template

A template in the context of CloudFormation is a JSON or YAML file that describes the AWS resources and their configuration. The script refers to templates as the blueprints for creating stacks in CloudFormation, which are collections of AWS resources that are created, updated, or deleted together.

💡Stack

A stack in CloudFormation is a collection of AWS resources that are created and managed together. The video script uses the term 'stack' to describe the process of creating, updating, and deleting a group of AWS resources as a single unit, which is a core concept in managing infrastructure as code.

💡S3

S3 stands for Simple Storage Service, which is an object storage service offered by AWS. In the script, S3 is mentioned as a place to upload the CloudFormation template file, demonstrating how resources can be stored and referenced in AWS for use in automation tasks.

💡Update Stack

Updating a stack in CloudFormation involves making changes to the stack's resources or template. The script explains the process of updating a stack by uploading a new template that includes additional resources like security groups and an Elastic IP, showing how CloudFormation can adapt to changing requirements.

💡Tagging

Tagging is the process of adding metadata to AWS resources to help organize and manage them. The video script mentions the use of tags in CloudFormation to label resources with specific information like 'course' and 'CloudFormation', which aids in resource identification and management.

💡Logical ID

A logical ID is a unique identifier used within a CloudFormation template to refer to resources. The script refers to the logical ID when discussing how resources are identified and managed within a CloudFormation stack, which is crucial for tracking and referencing specific resources.

💡Delete Stack

Deleting a stack in CloudFormation is the process of removing all the resources associated with that stack. The script concludes with the demonstration of deleting a stack, which results in the cleanup of all resources that were created through CloudFormation, emphasizing the automation of resource management.

Highlights

Introduction to creating a simple EC2 instance using AWS CloudFormation.

Explanation of EC2 instances as servers in AWS available on-demand.

Guidance on adding an Elastic IP to an EC2 instance for static IP addressing.

Demonstration of assigning two security groups to an EC2 instance for enhanced security.

Emphasis on ignoring code syntax for now to focus on CloudFormation template creation and updates.

Instructions to use the North Virginia US East region for consistency during the course.

Step-by-step guide on how to upload a CloudFormation template from Amazon S3.

Tutorial on specifying a stack name and adding resource tags in CloudFormation.

Overview of the CloudFormation stack creation process and its status updates.

Description of the event log in CloudFormation for tracking the creation and update of resources.

Explanation of how CloudFormation automatically applies tags to resources based on the stack.

Illustration of managing and customizing AWS resources through CloudFormation tags.

Process of updating a CloudFormation stack with new resources like security groups and an Elastic IP.

Clarification that CloudFormation templates cannot be edited directly but require uploading a new template.

Demonstration of previewing changes before updating a CloudFormation stack.

Observation of CloudFormation's intelligent handling of resource creation and deletion order.

Highlight of CloudFormation's self-cleaning feature after updates by terminating old instances.

Tutorial on deleting a CloudFormation stack to clean up all associated resources.

Conclusion emphasizing the power and efficiency of CloudFormation for managing AWS resources.

Transcripts

okay so let's get started with some

hands-on example around cloud formation

in this example when you create a simple

ec2 instance and ec2 instances pretty

much everyone knows about it it's the

server's in AWS that you can get on

demand we're also going to create and

add an elastic IP to that instance and

we're also going to add two security

groups to it for now I want you to

forget about the code syntax I want you

to forget about what is the content of

the template just for now we'll do a

much bigger deeper dive later on in this

course what I'm going to focus on is how

it creates my alias CloudFormation

template how it's being updated what

happens in my alias account and so on

okay so we'll see how in no time you are

able to get started with cloud formation

so hopefully in the previous lecture you

did download the code it was attached in

the resources so you should have the

code by now so here is your areas

console and I just created my accounts

if you don't have one should create one

obviously you do is tap it with cloud

signup and you have it when you're

logged in you see this screen the first

thing I want to make sure is that for

the rest of this class just to make sure

we're on the same page I want you to

work in a North Virginia US East region

and that's called USGS one and the only

reason is I want you to have the exact

same setup as me

it doesn't matter when you get to work

into your own region you can change the

region later on but for this course

please bear with me and please use the

US East North Virginia region okay so if

you find CloudFormation you click on

services and then you just type in cloud

formation and this is the first link we

are being greeted by the screen which

prompts us to create stack stack set

designing a template or from educating

resources for now we're just going to

create a new stack when we get into that

screen it's ask us for a template we can

either design a template and we'll go

over that's in there for next lectures

or we can choose a template we can

select from some templates that they

already have for us we can upload a file

to Amazonas

three or specify an Amazon s3 template

URL so what we notice is already that

either we do something in the cloud or

directly we have to select something

that lives already in Amazon s3 so we'll

choose upload a template Amazon s3 now

if we look at the templates

we'll have to we have just easy to and

easy to is security group II IP which is

the more complex one so we'll just start

with just ec2 and you can have a look

already but what this will do is that it

will create one ec2 instance in the US

east one a availability zone and there

will be a teacher micro which is part of

the free tier so what I'll do is I'll

just upload this file for this there

easy

I choose a file and I click on 0 just

ec2 alright so far so good then we click

Next and the template is being uploaded

to Amazon s3

and it's being validated now we have to

specify it's stacked a stack name for

this I will call it introduction and you

can choose whatever you want but I like

to call things but what they are this is

an introduction so we'll call this

introduction

next you are able to specify some tags

in your resources and tags we'll just

add one the name of the tag will be

course and the value will be

CloudFormation just to show you what

this does when we do create these

resources we have a bunch of Advanced

Options we'll go over there later on

next here is our template URL it has

been uploaded through Amazon s3 there's

no description here we can estimate the

class booking on a cost the stock name

is introduction we have a tag name

confirmation and that's about it and we

click on creates so here we go we see

now the screen is being populated with

the stock name introduction and has been

created at this time and the status is

created in progress

so while we wait basically what this

will do is that it will go ahead and

create whatever was in a CloudFormation

document in which case what we had was

just an ec2 instance

so this CloudFormation template will not

go green up until that ec2 instance has

been created and is working ok so that's

why right now you see create in progress

the really cool thing though is that you

can refresh obviously and you see that

there's an events tab right here which

tells you exactly with the timestamp how

the events are going for example I

started at 22 29 32 and 26 seconds later

the create was completes ok so you can

see all the events into one very nice

timeline now if you go to overview

there's nothing new I put nothing but if

we go to resources now we see that there

is an ec2 instance that has been create

complete and the logical idea is my

instance so if you click on it and open

it in a new tab we get redirected to the

ec2 management console and we see right

here that we have our instance I opposed

to just teach you micro in the

availability zone that we wanted u.s. 1a

and it's been created so pretty amazing

right we just dumped a file into cloud

formation around the cloud formation and

all of a sudden we end up with an issue

2 instance what's even better is that if

you go to tags we can see that this

instance has been tagged with a lot of

things already first of all there is

this course CloudFormation tag that I

specified during the lunch so what that

means that for your cloud formations any

tags that you specify in the cloud

formation prompts will be applied to any

resource in the stack which is amazing

but also you inherit three areas

specific tags based on cloud formation

the number one is the logical idea of

the thing which is my instance the

second one is the stack ID

it belongs to my big AR n stack and

finally this tech name which was cool

introduction so that's really cool

because from a management and from a

custom perspective you have lots and

lots of control over which instance is

tagged with what what it belongs to and

so on so it's pretty amazing

so to summarize I've created a cloud

formation template

and has just an easy-to instance now say

you go you go you go and guess what

things change your boss asked for two

security groups and an elastic IP as we

can see right now there are no security

groups there's just a default one okay

and there is no elastic IP just a public

IP but it was random so let's go ahead

and edit this cloud formation templates

well it turns out you can't edit

CloudFormation template instead what you

have to do is to provide a new cloud

formation templates so let's do this

we're going to click on update stack and

we get right back to that first screen

of selected templates again we have to

upload a new file okay we can't edit

what already existed we have to plot a

new file and now we have one easy to

with s G and E IP if you don't look at

the code again we'll go an emerge deeper

dive later on in this course but now we

have our instance and it has two

security groups which are defined right

here but also it has an elastic IP and

that elastic IP belongs to my instance

so let's to take on again it believe me

that basically creates the resources and

links them together ok so I would put

the file I click on next and I'm going

to be asked to review the cloud

formation name and as you can see this

is grayed out we can't change the name

after it's been created ok so if you do

specify a stack name you can't change it

later you have to delete your task stack

and recreate it to change the name press

next and as you can see we can add more

tags we can delete the previous ones

it's pretty cool ok anyway what we'll do

is go on next and what we see is that we

can review what's happening there's a

new template URL the stack names the

same the tags are the same but oh here

we go

something happens cloud formations tells

us there's going to be changes and of

course they're gonna be changes because

we did upload a new templates but what's

really

is that we can preview what the changes

are going to be and that's really nice

because if you were to change something

you really want to make sure that you're

not you know messing things around so

here we go we're going to add an elastic

IP and it says add we're going to modify

our ec2 instance okay and because we

added security groups to it and that

change actually will trigger a

replacement of that instance so very

good to know that previous one will be

replaced entirely finally we'll have two

security groups that will be created all

right so yeah I'm pretty happy with this

changes I'll click on updates and here

we go so now if we look at the events

log again the previous events are kept

but now we are into an update in

progress events so as I as a refresh we

can see that the event is getting more

and more populated for example here it

created my two security groups and now

it's going to create my ec2 instance so

it's going to create a whole new one and

stuff so as I let it happen basically

Arius CloudFormation figures out the

order in which things need to happen it

understood that first you needed to

create the security groups before you

could create the ec2 instance and that's

why the security rules were created

first and then my ec2 instance was being

created so if you're crippling freshing

for example once the ec2 instance has

been created then we can go ahead and

have our elastic IP being created and

finally once the elastic IP is created

which might take a while it weighs we'll

go and remove the old ec2 instance so

one more refresh

anyway in the meantime what we can do is

go to resources and as you can see now

in the resources we don't see one item

though and now we see four items we see

that we have two security groups my

instance and an elastic IP that has this

IP and that's really cool because

everything was provisioned from within a

template okay so as we've seen here

every resources has been created

successfully and some were created

somewhere updated and then finally in

the event log is going to delete the old

database instance that we didn't use

okay so let's go ahead and review all

these resources if we go to the

management console we see that the new

instance is running but now it has two

security groups attached to them so

let's just go and go to the security

groups and if you check the security

groups we can see that the group name is

introduction which is the name of my

stack and then the idea of my group and

some random number the tags are what we

expect them to be here is the course

CloudFormation tag and it has the right

rules we assign them to this is my

second group right here and again the

tags are correct

the group name is different obviously

and so on finally if we check something

the elastic IP parent has been defined

and we can open it and again obviously

you know what if you guess now the

elastic IP will be exactly what we want

it to be okay anyone have the right

association so it's all very very very

very nice but finally let's look at what

happened the previous instance got

terminated so on top of like creating a

new instance areas cloud formation was

smart enough to say wait wait I'm going

to terminate the old instance because my

user doesn't want it anymore and it went

ahead and terminated it so that's

awesome

because it just cleaned up after itself

and that's really cool that's something

we can see in the events log and for

example here

the cleanup was happening and it was

delete

the old instance and completing the

deletes so so far we've seen a create an

updates and to finish this little part

of the tutorial say we want to delete

say we want to clean up what we did

because we created one is you to

instance we have created two security

groups and we have created elastic IPS

so how do we go about and cleaning

everything do I go here and and

terminate and everything or or is there

a better way or in fact there's a better

way if you go to the cloud formation

right-click and say delete stack it will

go ahead and delete all the stack

resources for you which is amazing

because everything you've created

through cloud formation will be deleted

with your cloud formation so I'll go

ahead and say yes deletes and the delete

is in progress and as you can guess it

will start deleting things in order as

well so you don't have to figure out

what to delete first and what not to

delete first it with cloud formation

will figure this out for you so as you

go ahead first will be deleted the

elastic IP then the instance and then

finally the security groups when all of

this is over

basically the cloud formation will

disappear and you can change the filter

to go and delete it so I'll just pause

when this is done so after using the

filter and everything disappears you can

see that you can just use the filters

get back to your CloudFormation template

and then you see that the event log

everything was being deleted and the

delete is complete so now if I go to my

management console and just refresh all

my instances have been terminated if I

go to my security groups my two new

secrets are gone and if I go to my

elastic IPS I would see the elastic IP

will be gone so it's really cool because

CloudFormation just cleaned up

everything in one click so here we just

witness the power of cloud formation for

creating updating and deleting errors

resources in no time