Now let's talk about
what powers our EC2 instances which is an AMI,
so AMI stands for Amazon machine image
and they represent a customization of an EC2 instance.
So you can use AMIs you created by AWS
or you can customize it into your own and what is in an AMI?
Well we have our own software configuration,
we can define and set up the operating system,
we can set up any monitoring tool
and if we create our own AMI
we're going to get a faster boot time and configuration time
because all the software that we want to install
onto our EC2 instance
is going to be prepackaged through the AMI.
So we have to build our own AMIs
and they can be built for a specific region
and then they can be copied across region
if we wanted to use it
and leverage the AWS global infrastructure.
So we can launch EC2 instances from different kind of AMIs.
What we've been doing so far in this course
is to use a public AMI and these are provided by AWS.
So the Amazon Linux 2 AMI is a very popular AMI for AWS
and it was provided by AWS themselves
but we can create our own AMI
then therefore you have to make and maintain them yourself
there are tools obviously to automate this
but this is a task that you have to do as a cloud user
or finally you can launch an EC2 instance
from an AWS Marketplace AMI
which is an AMI that has been made by someone else
and potentially sold by someone else
so it is quite common to have vendors on AWS
to create their own AMIs or their own software
with a nice configuration and so on
and then they will sell it through the marketplace AMI
for you to buy it and to save some time.
And even you as a user you could create a business
of selling AMIs on the AWS marketplace,
this is something that some businesses do.
Okay so the AMI process from an EC2 instance,
how does it work?
Well we'll start an EC2 instance and we'll customize it.
Then we will stop the instance
to make sure the data integrity is correct,
then we can build an AMI from it
so this will also create EBS snapshots behind the scenes
and then finally we can launch instances from other AMIs
so this is what we'll be doing
in the demo and the next lecture.
So we have US-EAST-1A,
and we can create the same instance as US-EAST-1B,
so the process is we launch the instance in US-EAST-1A,
we're going to customize it
then we're going to create an AMI from it
this will be our custom AMI.
And then in US-EAST-1B
we will be able to launch from that AMI
and we'll effectively create a copy of our EC2 instance.
So I hope you're excited
and I will see you in the next lecture.