‫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.