EC2 - EBS/EBS Volume Types/Encryption

Question 1

What does EBS stand for in AWS?

Answer 1

EBS stands for Elastic Block Store. It is a network drive that you can attach to EC2 instances.

Question 2

What is the primary purpose of EBS Volumes?

Answer 2

EBS Volumes allow data to persist even after the EC2 instance is terminated. You can recreate an instance and mount the same EBS volume to access the data.

Question 3

Can an EBS Volume be mounted to multiple EC2 instances at once?

Answer 3

No, an EBS Volume can only be mounted to one EC2 instance at a time.

Question 4

How are EBS Volumes tied to Availability Zones (AZs)?

Answer 4

EBS Volumes are bound to a specific AZ and cannot be attached to instances in different AZs. However, you can move them across AZs using snapshots.

Question 5

How can you think of EBS Volumes in simple terms?

Answer 5

EBS Volumes can be thought of as network USB sticks that you can attach to EC2 instances over the network.

Question 6

What is the default free tier offering for EBS Volumes in AWS?

Answer 6

AWS provides 30 GB of General Purpose SSD (GP2) or Magnetic storage per month in the free tier.

Question 7

How do EC2 instances communicate with EBS Volumes?

Answer 7

EC2 instances communicate with EBS Volumes over the network, which may introduce some latency.

Question 8

What is the capacity provisioning requirement for EBS Volumes?

Answer 8

You must provision capacity in advance, specifying the number of GBs and IOPS (I/O operations per second) for the volume.

Question 9

Can an EBS Volume be detached and re-attached to another EC2 instance?

Answer 9

Yes, EBS Volumes can be detached from one EC2 instance and attached to another quickly, making them useful for failovers.

Question 10

Can EBS Volumes be created without being immediately attached to an EC2 instance?

Answer 10

Yes, EBS Volumes can be created unattached and attached to EC2 instances on demand.

Question 11

What is the “Delete on Termination” attribute for EBS Volumes?

Answer 11

The Delete on Termination attribute controls whether an EBS Volume is deleted when the EC2 instance is terminated. By default, it is enabled for the root volume, but disabled for additional EBS Volumes.

Question 12

What is the use case for disabling the “Delete on Termination” attribute?

Answer 12

If you want to preserve the root EBS volume when an EC2 instance is terminated (e.g., to save data), you can disable the “Delete on Termination” attribute for the root volume.

Question 13

What is an EBS Snapshot?

Answer 13

An EBS Snapshot is a backup of an EBS volume at a specific point in time.

Question 14

Is it necessary to detach an EBS volume before taking a snapshot?

Answer 14

No, it’s not necessary to detach the EBS volume, but it is recommended.

Question 15

Can you copy EBS Snapshots across Availability Zones (AZs) or Regions?

Answer 15

Yes, you can copy EBS Snapshots across different Availability Zones or even across Regions.

Question 16

How can you transfer an EBS volume from one Availability Zone (AZ) to another?

Answer 16

You can take a snapshot of the EBS volume and then restore it in a different AZ to transfer the volume.

Question 17

What is the EBS Snapshot Archive feature?

Answer 17

The EBS Snapshot Archive allows you to move snapshots to an archive tier, which is up to 75% cheaper. However, restoring from the archive can take 24 to 72 hours.

Question 18

What is the EBS Snapshot Recycle Bin?

Answer 18

The Recycle Bin stores deleted EBS Snapshots, allowing you to recover them in case of accidental deletion. The retention period can be set from 1 day to 1 year.

Question 19

What is the Fast Snapshot Restore feature?

Answer 19

Fast Snapshot Restore forces a full initialization of your snapshot to eliminate latency on the first use. It’s helpful for large snapshots but is an expensive feature.

Question 20

What are the six types of EBS volumes?

Answer 20

gp2 and gp3 (General Purpose SSD)
io1 and io2 Block Express (Provisioned IOPS SSD)
st1 (Throughput Optimized HDD)
sc1 (Cold HDD)

Question 21

What is the primary use case for gp2 and gp3 volumes?

Answer 21

gp2 and gp3 are general-purpose SSD volumes suitable for cost-effective storage, low-latency needs, and varied workloads like system boot volumes, development, and test environments.

Question 22

What type of workloads benefit from io1 and io2 volumes?

Answer 22

io1 and io2 volumes are used for mission-critical applications that require consistent high performance or database workloads that need more than 16,000 IOPS.

Question 23

What types of workloads are suitable for st1 volumes?

Answer 23

st1 is a low-cost HDD designed for throughput-intensive workloads like big data, data warehousing, and log processing.

Question 24

What is the primary use case for sc1 volumes?

Answer 24

sc1 is a cold HDD volume used for infrequently accessed data or archive storage, offering lower cost with 250 MB/s throughput and 250 IOPS.

Question 25

Which volume types can be used as boot volumes for EC2 instances?

Answer 25

gp2, gp3, io1, and io2 can be used as boot volumes for EC2 instances.

Question 26

What is the difference between st1 and sc1?

Answer 26

st1 is designed for frequently accessed, throughput-intensive workloads like data warehousing. sc1 is designed for infrequently accessed, cold storage or archive data with the lowest cost.

Question 27

What is a key takeaway for the AWS exam regarding EBS volumes?

Answer 27

Focus on the general purpose SSD (gp2/gp3) for cost-effective solutions, provisioned IOPS SSD (io1/io2) for high-performance workloads, and st1/sc1 for cost-effective, high-throughput storage.

Question 28

What is the Multi-Attach feature in EBS volumes?

Answer 28

The Multi-Attach feature allows you to attach the same io2 or io1 EBS volume to multiple EC2 instances within the same Availability Zone.

Question 29

Which types of EBS volumes support the Multi-Attach feature?

Answer 29

The Multi-Attach feature is only available for io1 and io2 EBS volumes.

Question 30

How many EC2 instances can attach to a single EBS volume using the Multi-Attach feature?

Answer 30

Up to 16 EC2 instances can attach to the same EBS volume using the Multi-Attach feature.

Question 31

What is the use case for the Multi-Attach feature?

Answer 31

The Multi-Attach feature is useful for higher application availability, such as in clustered Linux applications or applications that must manage concurrent write operations (e.g., Teradata).

Question 32

What is a key limitation of the Multi-Attach feature?

Answer 32

The Multi-Attach feature can only be used within the same Availability Zone and cannot attach an EBS volume across different Availability Zones.

Question 33

What type of file system is required to use the Multi-Attach feature?

Answer 33

You must use a cluster-aware file system (such as Clustered XFS or Clustered EX4) for the Multi-Attach feature to work. Standard file systems like XFS or EXT4 are not supported.

Question 34

What permissions do EC2 instances have when using the Multi-Attach feature?

Answer 34

Each EC2 instance attached to the io1 or io2 volume will have full read and write permissions to the volume.

Question 35

Why is the Multi-Attach feature useful for applications?

Answer 35

It enables high availability and concurrent write operations in clustered applications, making it ideal for workloads that need shared access to high-performance storage.

Question 36

What happens when you create an encrypted EBS volume?

Answer 36

When you create an encrypted EBS volume, the following happens: Data at rest is encrypted inside the volume. Data in transit (between the instance and the volume) is encrypted. Snapshots of the volume are encrypted. Volumes created from the snapshots are encrypted. The encryption and decryption processes are handled transparently by EC2 and EBS.

Question 37

3. Does enabling encryption on an EBS volume impact latency?

Answer 37

No, the impact on latency is minimal, and encryption is handled transparently with little or no performance impact.

Question 38

How do you encrypt an unencrypted EBS volume?

Answer 38

To encrypt an unencrypted EBS volume, follow these steps: Create a snapshot of the volume. Copy the snapshot, enabling encryption during the copy process. Create a new EBS volume from the encrypted snapshot. Attach the newly encrypted volume to the original EC2 instance.

Question 39

What happens to the encryption setting when you create a snapshot from an unencrypted EBS volume?

Answer 39

The snapshot will inherit the unencrypted setting, meaning it will not be encrypted by default.

Question 40

Is it possible to create an encrypted volume directly from an unencrypted snapshot?

Answer 40

Yes, you can create an encrypted volume directly from an unencrypted snapshot by selecting the encryption option during the volume creation process.