EC2 Hibernate

Question 1

What is the difference between stopping an EC2 Instance and terminating an EC2 instance?

Answer 1

• If we stop the instance, data is kept on the disk (with EBS) and remains on the disk until the EC2 instance is started again.
• If the instance is terminated, then (by default) the RDV will also be terminated

Question 2

In order, what are the three things that happen when you start an EC2 instance?

Answer 2

1. The Operating System boots up
2. The user data script (bootstrap scripts) are run
3. Applications start (can take some time)

Question 3

With EC2 Hibernate, what happens when you start your instance out of hibernation?

Answer 3

• The EBS root volume is restored to its previous state
• The RAM contents are reloaded
• The processes that were previously running on the instance are resumed
• Previously attached data volumes are reattached and the instance retains its instance ID

Question 4

With EC2 Hibernate, what happens when you hibernate an instance?

Answer 4

• The OS is told to perform a hibernation (suspend-to-disk)
• Hibernation saves the contents from the instance memory (RAM) to its EBS root volume and any attached Amazon EBS data volumes

Question 5

What is the core benefit of EC2 Hibernate?

Answer 5

It is much faster to load up because the OS does not need to reboot becuase the in-memory state (RAM) is preserved.

Question 6

What Instance families are eligible for EC2 Hibernate?

Answer 6

C3, C4, C5, M3, M4, M5, R3, R4, R5

_{{C, M, R} x {3, 4, 5}}

Question 7

For what types of use cases is EC2 Hibernate most useful?

Answer 7

• Long-running Processes
• Services that take a long time to initialize

Question 8

What is the limit on the RAM size of an EC2 instance in order to use EC2 Hibernate?

Answer 8

150 GB

Question 9

For what operating systems is EC2 Hibernate available?

Answer 9

• Windows
• Amazon Linux 2 AMI
• Ubuntu

Question 10

For how long does EC2 Hibernate allow you to hibernate an instance?

Answer 10

up to 60 days

Question 11

For what types of EC2 Instance pricing structures is EC2 Hibernate available?

Answer 11

On-Demand Instances and Reserved Instances

Question 12

What is the difference between stopping an EC2 Instance and hibernating it?

Answer 12

• Minor Billing Difference:
  
  • When hibernating, you get billed while the instance is in the stopping state, but not while it is stopped
  • When stopping, you stop getting billed once the instance is in the stopping state.
• Contents of Memory (RAM):
  
  • When hibernating, the memory contents (RAM) is saved to a file on the root device,
  • When stopping, the RAM is erased