EC2 Instance State Recommendation and Best practice

• When you launch an Instance, it goes through Pending then Running state.
• Moving to Running state means the instance has started booting.
• Then the instance receives a Private DNS Hostname and possibly a Public DNS Hostname (Depends on whether it is configured to receive public IP address).
• If you reboot an EC2 Instance, it is considered as Running and does not add additional hour for your bill (Not applicable for per second billing).
• Stopping and Starting add an hour to your billing.
• When you stop an Instance AWS shuts it down.
• A Stopped Instance maintains its Instance ID and root volume (if its EBS backed).
• Instance store backed instance CANNOT be Stopped, they can only be Rebooted and Terminated.
• No Charges for Stopped EC2 Instance but EBS incur charges.
• For Stopped EC2 Instance you can detach/re-attach EBS volume including root volume.
• When you stop an EBS backed EC2 Instance, any data in Instance store volume is lost (Even if you restart later, all instance store data would be lost).
• Instance Performs Shutdown (State changes from Running-Stopping-Stopped).
• EBS volumes remains attached to EC2.
• Any data in Instance store volume is lost.
• When EC2 is restarted it will go on another physical host (likely).