Introduction

When running applications on Amazon EC2, it's important to have a way to back up your instances and restore them in case of failure or data loss. One easy way to do this is by creating AMI (Amazon Machine Image) snapshots. In this post, I'll explain how to create AMI backups and restore EC2 instances using the AMI.

Creating an AMI from an EC2 Instance

Here are the steps to create an AMI backup from an existing EC2 instance:

1. In the AWS Management Console, select the EC2 instance and choose "Actions > Image > Create Image".

2. Specify details like the Image name, Description, Volume details.

3. Click "Create Image". AWS will shut down the instance, snapshot all the volumes, and register a new AMI.

You can also create AMIs via the AWS CLI:

aws ec2 create-image --instance-id i-0abcd1234efg567 --name "My Server Backup" --description "Backup AMI of my server"

This will create an AMI in your AWS account with the given details.

Launching a New EC2 Instance from an AMI

Once you have created an AMI, you can launch a fully restored instance from this image backup:

1. In the EC2 Dashboard, click "Launch Instance"

2. Select the AMI from the list and continue the wizard.

3. Configure the instance details and launch as normal.

A new EC2 instance will be launched from the AMI snapshot. All data and settings will be restored from when the AMI was created.

You can also launch instances from an AMI using the AWS CLI:

aws ec2 run-instances --image-id ami-0abcd1234efg567 --count 1 --instance-type t2.micro --key-name my-key

Automating AMI Backups and Restores with Terraform

We can automate AMI creation and instance restoring using Infrastructure as Code tools like Terraform.

Here is an example of Terraform configuration:

# Create AWS AMI resource
resource "aws_ami" "web_server_ami" {
  name                = "Web Server AMI Backup"
  description         = "AMI backup of web server" 
  source_instance_id  = aws_instance.web_server.id
}

# Launch EC2 instance from AMI
resource "aws_instance" "web_server_from_ami" {
  ami           = aws_ami.web_server_ami.id
  instance_type = "t2.micro"  
}

This allows us to keep the AMI creation and restore process automated and under version control.

Conclusion

Automating AMI backups with Terraform provides a repeatable way to protect your EC2 instances. Be sure to test restores regularly!

Let me know if you have any other questions.