Difference Between A Snapshot And AMI In AWS

Snapshots and AMIs are the techniques used to create backups and templates to easily create copies of EBS. AMI has revolutionized cloud computing by encapsulating the configuration, underlying operating system, and software packages that are required to launch an instance in AWS.

Snapshots, on the other hand, capture the state of volume and provide a reliable mechanism for data backup, disaster recovery, and migrating volume. Snapshots are designed to be incrementable so that a new snapshot only stores the changes that were made in the last snapshot and thus utilizes the space.

What Is AWS Snapshot?

Amazon web services are point-in-time copies of data stored in the volume of AWS EBS (Elastic Block Store) or Redshift instances. A snapshot is used to backup, restore, or replicate the volume that contains the exact information at a particular time. It is a reliable backup mechanism to preserve data and restore it safely.

Snapshots taken are stored in Amazon S3, which is a type of storage service provided by AWS. Whenever a snapshot is taken, AWS takes a copy of the designated volume where the snapshot was taken; it could be either EC2 or Redshift. Only data inside the volume is copied so that it can be used for restoration.

AWS snapshot follows an incremental backup approach, i.e., every time a snapshot is taken, AWS only stores the changes in volume from the last snapshot created. Initially, snapshots incur only storage costs without any additional cost beyond regular storage fees, but multiple snapshots at regular intervals incur additional costs like data transfer costs and lifecycle management costs.

What Is AWS Amazon Machine Image?

AWS AMI stands for Amazon Machine Image and is a backup of the entire EC2 instance along with its root volume information and configurations. An EC2 can be connected to various other resources, like security groups and volumes. AMI can be used to further create duplicate instances or back up the AMI in case of failure.

Both of the point-in-time backups are useful in their respective fields. AMI is used to duplicate the entire EC2, which is useful in spawning new servers without the headache of configuring them again, and Snapshot is used to create the point-in-time image of the volume, which can be further recreated in case of failure.

The AMI cost is as similar as the snapshot cost. However, AMI captures machine information as well as the volume state; it takes more space, data transfer, and life cycle management costs as compared to the snapshot.

AWS Snapshot VS AWS AMI

Snapshot	AMI
A snapshot is an image of the volume at any particular instant.	AMI is an image of the entire EC2 instance at any particular instant, including all the resources EC2 is holding.
A snapshot is used to back up the disk in case of any failure or inconsistency.	AMI is used to back up the entire EC2 instance, including all the resources to recreate the server in the event of its failure.
Snapshots are used to restore volumes or create existing ones.	AMI is a template that can be used to create an EC2 instance exactly the same as the EC2 instance when the image was taken at a particular instance.
Snapshots are used inside the AMI in order to store information and configure volume.	AMI can be found by either AWS or the community and can be custom-created by any user.
Snapshots are stored in Amazon S3, and they are highly durable.	AMI can be customized with specific software, configuration, and permissions.

In case of failure, the first snapshot is applied in order to fix the issues caused by disk inconsistency, and if the problem still persists, the AMI backup is created in order to fix issues caused by inconsistency or misconfiguration of the EC2 instance.

Conclusion

Thus, we can conclude that AWS provides two major features. Snapshots and AMI allow you to create backups, restore them, and replicate the previously created instance with ease. These methods make the AWS cloud more reliable and safe since data is very important in the current world. Snapshots and AMI can also be used to improve the developer’s productivity by taking AMI images of instances that need to be created several times. AWS recommends periodically taking snapshots of volumes so that any kind of instance can be restored to its very close, consistent state without any failure or loss of data.

AWS Snapshot and AMI – FAQ’s

What is the difference between AWS Snapshots and AWS AMIs ?

AWS snapshot is the point in time backup of the EBS volume, capturing its complete information in Amazon S3 while AWS AMIs are the template of the instance including it’s operating system, configuration and their software packages that are required to launch an intsance.

How do I create a snapshot in AWS ?

AWS snapshot can be created by either using AWS Management Console CLI or AWS SDK . We need to select the volume we want to take snapshot and click on create snapshot from navigation. It popups for some information about the snapshot name and description, simply fill them and click on create snapshot.

What are the best practices about AWS snapshot ?

AWS snapshot should be taken at regular interval. It is suggested to encrypt the snapshots which are sensitive to keep them confidential.

How do I create an AMI from existing EC2 instance ?

To create an AMI from EC2 instance simply select the instance which you want to create AMI and then select Create Image or Create AMI option. You will be asked with the basic details about image like the image name and description, fill the details and click on Create Image.