When an EC2 EBS-backed (EBS root) instance is stopped, what happens to the data on any
ephemeral store volumes?
A.
Data is automatically saved in an EBS volume.
B.
Data is unavailable until the instance is restarted.
C.
Data will be deleted and will no longer be accessible.
D.
Data is automatically saved as an EBS snapshot.
Explanation:
An “EBS-backed” instance is an EC2 instance which uses an EBS volume as it’s root device.
An EBS volume behaves like a raw, unformatted, external block device that you can attach to
a single instance and are not physically attached to the Instance host computer (more like a
network attached storage). The volume persists independently from the running life of an
instance. After an EBS volume is attached to an instance, you can use it like any other
physical hard drive. You can also detach an EBS volume from one instance and attach it to
another instance. EBS volumes can also be created as encrypted volumes using the Amazon
EBS encryption feature.
Ephemeral disk is a temporary storage that it is added to your instance, and depending on your instance type the bigger is such storage.
I believe the answer should be A – Data is automatically saved in an EBS volume.
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/RootDeviceStorage.html
Instances that use Amazon EBS for the root device automatically have an Amazon EBS volume attached. When you launch an Amazon EBS-backed instance, we create an Amazon EBS volume for each Amazon EBS snapshot referenced by the AMI you use. You can optionally use other Amazon EBS volumes or instance store volumes, depending on the instance type.
An Amazon EBS-backed instance can be stopped and later restarted without affecting data stored in the attached volumes.
A
Yes, A should be correct.
If the question mentioned it is instance strore-backed instance, C will be correct.
After an instance store-backed instance fails or terminates, it cannot be restored. If you plan to use Amazon EC2 instance store-backed instances, we highly recommend that you distribute the data on your instance stores across multiple Availability Zones. You should also back up critical data on your instance store volumes to persistent storage on a regular basis.
Which one is correct? I think an EBS backed instance would use EBS volume instead of ephemeral disk.
I think C is correct.
http://jayendrapatil.com/aws-ebs-vs-instance-store/
Data on Instance store volume is LOST in following scenarios :-
Failure of an underlying drive
Stopping an EBS-backed instance where instance store are additional volumes
And in order to avoid any further pointless discussion – I just tested it with an i3.large instance with an additional instance store and on restart the ephemeral storage is flushed, i.e. deleted. Therefore – C.
Data persistence
By default, the root volume is deleted when the instance terminates.* Data on any other Amazon EBS volumes persists after instance termination by default. Data on any instance store volumes persists only during the life of the instance.
Stopped state
Can be placed in stopped state where instance is not running, but the root volume is persisted in Amazon EBS