EC2 - EBS/EBS Volume Types/Encryption Flashcards
What does EBS stand for in AWS?
EBS stands for Elastic Block Store. It is a network drive that you can attach to EC2 instances.
What is the primary purpose of EBS Volumes?
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.
Can an EBS Volume be mounted to multiple EC2 instances at once?
No, an EBS Volume can only be mounted to one EC2 instance at a time.
How are EBS Volumes tied to Availability Zones (AZs)?
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.
How can you think of EBS Volumes in simple terms?
EBS Volumes can be thought of as network USB sticks that you can attach to EC2 instances over the network.
What is the default free tier offering for EBS Volumes in AWS?
AWS provides 30 GB of General Purpose SSD (GP2) or Magnetic storage per month in the free tier.
How do EC2 instances communicate with EBS Volumes?
EC2 instances communicate with EBS Volumes over the network, which may introduce some latency.
What is the capacity provisioning requirement for EBS Volumes?
You must provision capacity in advance, specifying the number of GBs and IOPS (I/O operations per second) for the volume.
Can an EBS Volume be detached and re-attached to another EC2 instance?
Yes, EBS Volumes can be detached from one EC2 instance and attached to another quickly, making them useful for failovers.
Can EBS Volumes be created without being immediately attached to an EC2 instance?
Yes, EBS Volumes can be created unattached and attached to EC2 instances on demand.
What is the “Delete on Termination” attribute for EBS Volumes?
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.
What is the use case for disabling the “Delete on Termination” attribute?
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.
What is an EBS Snapshot?
An EBS Snapshot is a backup of an EBS volume at a specific point in time.
Is it necessary to detach an EBS volume before taking a snapshot?
No, it’s not necessary to detach the EBS volume, but it is recommended.
Can you copy EBS Snapshots across Availability Zones (AZs) or Regions?
Yes, you can copy EBS Snapshots across different Availability Zones or even across Regions.
How can you transfer an EBS volume from one Availability Zone (AZ) to another?
You can take a snapshot of the EBS volume and then restore it in a different AZ to transfer the volume.
What is the EBS Snapshot Archive feature?
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.
What is the EBS Snapshot Recycle Bin?
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.
What is the Fast Snapshot Restore feature?
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.
What are the six types of EBS volumes?
gp2 and gp3 (General Purpose SSD)
io1 and io2 Block Express (Provisioned IOPS SSD)
st1 (Throughput Optimized HDD)
sc1 (Cold HDD)
What is the primary use case for gp2 and gp3 volumes?
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.
What type of workloads benefit from io1 and io2 volumes?
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.
What types of workloads are suitable for st1 volumes?
st1 is a low-cost HDD designed for throughput-intensive workloads like big data, data warehousing, and log processing.
What is the primary use case for sc1 volumes?
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.
Which volume types can be used as boot volumes for EC2 instances?
gp2, gp3, io1, and io2 can be used as boot volumes for EC2 instances.
What is the difference between st1 and sc1?
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.
What is a key takeaway for the AWS exam regarding EBS volumes?
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.
What is the Multi-Attach feature in EBS volumes?
The Multi-Attach feature allows you to attach the same io2 or io1 EBS volume to multiple EC2 instances within the same Availability Zone.
Which types of EBS volumes support the Multi-Attach feature?
The Multi-Attach feature is only available for io1 and io2 EBS volumes.
How many EC2 instances can attach to a single EBS volume using the Multi-Attach feature?
Up to 16 EC2 instances can attach to the same EBS volume using the Multi-Attach feature.
What is the use case for the Multi-Attach feature?
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).
What is a key limitation of the Multi-Attach feature?
The Multi-Attach feature can only be used within the same Availability Zone and cannot attach an EBS volume across different Availability Zones.
What type of file system is required to use the Multi-Attach feature?
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.
What permissions do EC2 instances have when using the Multi-Attach feature?
Each EC2 instance attached to the io1 or io2 volume will have full read and write permissions to the volume.
Why is the Multi-Attach feature useful for applications?
It enables high availability and concurrent write operations in clustered applications, making it ideal for workloads that need shared access to high-performance storage.
What happens when you create an encrypted EBS volume?
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.
- Does enabling encryption on an EBS volume impact latency?
No, the impact on latency is minimal, and encryption is handled transparently with little or no performance impact.
How do you encrypt an unencrypted EBS volume?
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.
What happens to the encryption setting when you create a snapshot from an unencrypted EBS volume?
The snapshot will inherit the unencrypted setting, meaning it will not be encrypted by default.
Is it possible to create an encrypted volume directly from an unencrypted snapshot?
Yes, you can create an encrypted volume directly from an unencrypted snapshot by selecting the encryption option during the volume creation process.
