EC2 - Instance Storages

Question 1

What is EBS?

Answer 1

Elastic Block Store

Question 2

What is an EBS Volume?

Answer 2

Network drive that can be attached to instances.

Question 3

Does EBS Volume persists data after instance termination?

Answer 3

Yes it does.

Question 4

How many instance can use 1 EBS volume?

Answer 4

One volume can connect only to one instance.

Question 5

What are the EBS Volume restrictions?

Answer 5

It is bound to Availability Zones.

Question 6

Can you have latency with EBS Volumes?

Answer 6

Yes, because they are network attached.

Question 7

What does Provisioned capacity means for an EBS Volume?

Answer 7

It means and EBS Volume has a fixed size in GBs and IOPS once its created. Billed by the porvisioned capacity.

Question 8

What is Delete on Termination attribute?

Answer 8

Controls the EBS behaviour when an EC2 instance terminates
* By default, the root EBS volume is deleted (attribute enabled)
* By default, any other attached EBS volume is not deleted (attribute disabled)

Question 9

What is a typical Delete on Termination attribute use case?

Answer 9

Preserve a root volume after termination.

Question 10

What is EBS Snapshot?

Answer 10

Its a backup of the volume at a point of time.

Question 11

Whats the usage of Snapshots?

Answer 11

• Can copy snapshots across AZs
• Backuping data

Question 12

What are the 3 EBS Snapshots features?

Answer 12

• EBS Snapshot Archive
• cheaper “archive tier”, takes 24 to 72 hours to restore
• Recycle Bin for Snapshots
• setup retention rules for snapshot deletion
• Fast Snapshot Restore (FSR)
• force full initialization of a snapshot to have no latency on the first use $$$

Question 13

How to protect retention rules?

Answer 13

With the rule lock settings: lock, unlock.

Question 14

What is AMI?

Answer 14

• Amazon Machine Image
• AMI are a customization of an EC2 instance

Question 15

What are AMI restricitions?

Answer 15

It is bound to a specific region. (Can be copied across regions).

Question 16

What are the 3 launch type of EC2 instances?

Answer 16

• Public AMI: AWS provided
• Own AMI: you make it, you maintain it
• AWS Marketplace AMI: made by someone else

Question 17

How to create an AMI?

Answer 17

1. Start an instance and do the customizations
2. Stop the instance
3. Build AMI, this will create an EBS Snapshot
4. Launch instances from the AMI

Question 18

What is EC2 Instance Store?

Answer 18

a high-performance hardware disk

Question 19

What is the difference in EC2 Instance Store comapred to EBS Volume?

Answer 19

• Better I/O performance
• EC2 Instance Store lose their storage if they’re stopped (ephemeral)
• Good for buffer / cache / scratch data / temporary content
• Risk of data loss if hardware fails
• Backups and Replication are your responsibility
• very high IOPS

Question 20

What are the main EBS Volume Types?

Answer 20

• gp2/gp3 : General purpose SSD volume that balances price and performance for
  a wide variety of workloads
• io1 / io2 (SSD): Highest-performance SSD volume for mission-critical low-latency or
  high-throughput workloads
• st1 (HDD): Low cost HDD volume designed for frequently accessed, throughput- intensive workloads
• sc1 (HDD): Lowest cost HDD volume designed for less frequently accessed workloads

Question 21

What are the EBS Volume characterizations?

Answer 21

Size | Throughput | IOPS (I/O Ops Per Sec)

Question 22

What type of EBS Volumes can be used for boot?

Answer 22

gp2, gp2, io1, io2

Question 23

What are the uses cases of General Purpose SSD Volumes?

Answer 23

• Cost effective storage, low-latency
• System boot volumes, Virtual desktops, Development and test environments
• 1 GiB - 16 TiB
• gp2 iops and size is linked
• gp3 iops and size is not linked

Question 24

What are the uses cases of Provisioned IOPS (PIOPS) SSD Volumes?

Answer 24

*Critical business applications with sustained IOPS performance
* Or applications that need more than 16,000 IOPS
* Great for databases workloads (sensitive to storage perf and consistency)
* Supports EBS Multi-attach

Question 25

What are the uses cases of Hard Disk Drives (HDD) Volumes?

Answer 25

* Cannot be a boot volume * 125 GiB to 16 TiB * Throughput Optimized HDD (st1) * Big Data, Data Warehouses, Log Processing * Cold HDD (sc1): * For data that is infrequently accessed * Scenarios where lowest cost is important

Question 26

What is EBS Multi-Attach?

Answer 26

* Attach the same EBS volume to multiple EC2 instances in the same AZ * use case: * Achieve higher application availability in clustered Linux applications (ex: Teradata) * Applications must manage concurrent write operations * Up to 16 EC2 Instances at a time

Question 27

What is EFS?

Answer 27

*Elastic File System * Managed NFS (network file system) that can be mounted on many EC2 * EFS works with EC2 instances in multi-AZ * Highly available, scalable, expensive (3x gp2), pay per use

Question 28

Whats the typical usage of EFS?

Answer 28

content management, web serving, data sharing, Wordpress

Question 29

Is EFS compatible with Windows AMIs?

Answer 29

No, it is compatible with Linux based AMIs.

Question 30

How does EFS scales?

Answer 30

* File system scales automatically, pay-per-use, no capacity planning!

Question 31

What are the EFS Storage Classes?

Answer 31

* Performance Mode (set at EFS creation time) * General Purpose (default) – latency-sensitive use cases (web server, CMS, etc…) * Max I/O – higher latency, throughput, highly parallel (big data, media processing) * Throughput Mode * Bursting – 1 TB = 50MiB/s + burst of up to 100MiB/s * Provisioned – set your throughput regardless of storage size, ex: 1 GiB/s for 1 TB storage * Elastic – automatically scales throughput up or down based on your workloads * Up to 3GiB/s for reads and 1GiB/s for writes * Used for unpredictable workloads

Question 32

What are the EFS Storage Tiers?

Answer 32

* Standard: frequently accessed files * Infrequent access (EFS-IA): lower price storage, Enable via policy

Question 33

What are the EFS Storage Tiers availabilities?

Answer 33

* Standard: Multi-AZ, great for prod * One Zone: One AZ, great for dev, backup enabled by default, compatible with IA (EFS One Zone-IA)

Question 34

Whats the diff between EBS and EFS?

Answer 34

EBS volume * one instance (except multi-attach io1/io2) * are locked at the Availability Zone (AZ) level * gp2: IO increases if the disk size increases * io1: can increase IO independently * To migrate an EBS volume across AZ * Take a snapshot * Restore the snapshot to another AZ * Root EBS Volumes of instances get terminated by default if the EC2 instance gets terminated. (you can disable that) EFS * Mounting 100s of instances across AZ * EFS share website files (WordPress) * Only for Linux Instances (POSIX) * EFS has a higher price point than EBS * Can leverage EFS-IA for cost savings