What is an Elastic Block Storage Volume?

• An EBS volume is a network volume/drive that you can attach to your EC2 instances while they run.
• It allows your instance to persist data, even after termination of the EC2 instance.
• They can only mounted to one instance at a time.
• They are bound to specific AZs.

NOTE: Think of them as Network USB Sticks

FREE TIER: 30GB of free EBS storage of General Purpose SSD or Magnetic Drive per month.

1. It is a Network Drive (i.e. Not a Physical Drive):

   • It uses network to communicate with EC2 instance, which means there might be a bit of latency.
   • It can also be detached from EC2 instance and can be attached to another quickly.

2. Its locked to An Availablity Zone:

   • An EBS in a “us-east1a” cannot be attached to “us-east-1b”.
   • To move a volume across an AZ you need to take snapshot of it.

3. Have a provisioned capacity(size in GB & IOPS)

   • You get billed for all the provisioned capacity.

4. By Default, the root EBS volume is deleted when an attached EC2 instance is terminated.

5. By Default, any other EBS volume linked to that EC2 instance isn’t deleted. This can be enabled by checking delete on termination.

Note: Multiple EBS can be attached to a single EC2 instance & and EBS instance can exist without EC2 as well.

• Make a backup (snapshot) of your EBS volume at a point in time.
• Not necessary to detach volume, to do snapshot, but its recommended.
• Can copy snapshots across AZs as well as Regions.

• Move a snapshot to an archive tier that is 75% cheaper.
• Takes within 24 to 72 hours for restoring the archives.

• Setup rules to retain deleted snapshots, so you can recover them after accidental deletion.
• Specify retention period (from 1 day to 1 year)