EBS

Question 1

of test questions related to EBS

Answer 1

4-5

Question 2

EBS

Answer 2

Elastic Block Store

- storage volumes you can attach to your EC2 instances

Question 3

What are ways you can use EBS?

Answer 3

Use them the same way you would use any system disk

• to create a file system
• run a database
• run an operating system
• to store data
• install applications

Question 4

Can EBS be used for mission critical data?

Answer 4

Yes, it is highly available = automatically replicated within a single AZ to protect against hardware failures

Question 5

How much downtime is required to increase capacity or change volume type?

Answer 5

No downtime required - it is scalable.

- You can make changes without downtime or performance impact

Question 6

IOPS

Answer 6

Input/Output per second

Question 7

GP2

Answer 7

General Purpose Solid State (SSD)

• a balance of price and performance
• 99.9% durability

Question 8

GP3

Answer 8

General Purpose SSD
- predictable
- can scale up for an additional fee
(don’t need to know the IOPS or MiB/s for the exam)

Question 9

What is GP2 good for?

Answer 9

• Good for boot volumes or development & test applications that are not latency sensitive
• 99.9% durability

Question 10

What is GP3 good for?

Answer 10

• applications that require high performance at low cost

- mySQL, Cassandra, virtual desktops, Hadoop analytics

Question 11

How much faster is the top performance of GP3 over GP2?

Answer 11

GP3 is 4x faster than the max throughput of GP2 volumes

Question 12

io1

Answer 12

Provisioned IOPS SSD - (PIOPS)

• the most expensive
• high performance options
• 99.9% durability

Question 13

What is io1 (PIOPS) good for?

Answer 13

• if you need more than 16,000 IOPS
• I/O-intensive applications
• large databases
• latency-sensitive workloads/transactions

Question 14

io2

Answer 14

Provisioned IOPS SSD

• latest generation
• higher durability - 99.999%
• same price as io1

Question 15

What is io2 (PIOPS) good for?

Answer 15

• I/O-intensive apps
• large databases
• latency-sensitive workloads
• applications that need high durability
• transactions

Question 16

st1

Answer 16

ST1 - Throughput Optimized Hard Disk Drive

• low cost HDD volume
• maximum throughput of 500 MB/s per volume

Question 17

What is st1 good for?

Answer 17

• frequently accessed, throughput-intensive workloads
• big data, data warehouse, ETLS and log processing
• cost effective way to store mountains of data

Question 18

Which types of EBS cannot be boot volumes?

Answer 18

st1 and sc1

Question 19

sc1

Answer 19

sc1 - Cold Hard Disk Drive

• lowest cost option
• poor performance

Question 20

What is sc1 good for?

Answer 20

• for cold data requiring fewer scans per day

- for applications where lowest cost is needed when performance is not a factor

Question 21

IOPS basics

Answer 21

IOPS:

• measures # of reads & writes per second
• important metric for quick transactions, low-latency apps, and transactional workloads
• the ability to action reads/writes very quickly

Question 22

Throughput basics

Answer 22

Throughput:

• measures # of bits read or written per second
• important metric for: Large datasets, large I/O sizes, complex queries
• the ability to deal with large datasets

Question 23

EBS volume

Answer 23

a virtual hard disk

- need a minimum of 1 volume per EC2 instance for the OS “root device volume”

Question 24

EBS Snapshot

Answer 24

an S3 snapshot is a point-in-time copy/backup of the volume

• snapshots are incremental, only the changed pieces are moved to S3 (like gitlab)
• saves space and time because only the changes get moved over
• first snapshot will take the longest to establish the baseline

Question 25

Snapshot consistency

Answer 25

stop the instance and detach the volume before doing a snapshot, this will allow any cached data to be saved

Question 26

if you take a snapshot of an encrypted EBS volume, will it be automatically encrypted?

Answer 26

yes

Question 27

Sharing Snapshots**

Answer 27

- you can share within the region where it was created - to share with other regions, you will need to copy them to the new destination region and then create an image once it is in the new region.

Question 28

Are volumes always in the same AZ as your EC2 instance?**

Answer 28

Yes

Question 29

What must you do when you resize the EBS volume on the fly?

Answer 29

must extend the filesystem in the OS so the OS can see the resized volume

Question 30

EBS Encryption

Answer 30

- uses a data key w/ industry standard AES-256 algorithm | - uses KMS & Customer-Managed Keys (CMKs)

Question 31

What do you get with an encrypted volume?*

Answer 31

End-to-End Encryption - data at rest is encrypted - data in flight moving between instance and volume is encrypted - all snapshots are encrypted - all volumes created from the snapshot are encrypted

Question 32

Steps to encrypt an unencrypted volume**

Answer 32

1) create a snapshot of the root device volume 2) create a copy of the snapshot and chose the encrypt option*** 3) Create an AMI from the encrypted snapshot* 4) Use the AMI to launch new encrypted instances

Question 33

EC2 Hibernation

Answer 33

when an EC2 instance is terminated, by default the root device volume is terminated Hibernation saves RAM to Root volume. When you wake it up everything is restored.

Question 34

What does EC2 hibernation do?*

Answer 34

- saves contents of instance memory (RAM) to your EBS root volume - persists the root volume and any attached EBS data volumes

Question 35

What happens when you wake EC2 up from hibernation?

Answer 35

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

Question 36

Why does an instance boot faster from hibernation?

Answer 36

The OS does not need to reboot b/c the RAM is preserved

Question 37

What is hibernation useful for?*

Answer 37

- long-running processes | - services that take a long time to initialize

Question 38

What is a restriction for hibernation

Answer 38

RAM must be less than 150 GB.

Question 39

What is max hibernation period?

Answer 39

60 days

Question 40

Which instance families can hibernate?

Answer 40

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