ELB

Question 1

ELB means

Answer 1

Elastic load balancer

Question 2

When is it appropriate to use a classic load balancer?

Answer 2

When you need to support legacy. Or when the Application Load Balancer is not approps.

Question 3

If you want to use EC2 classic and a load balancer. What load balancer will be required?

Answer 3

The classic.

Question 4

Name the three types of ELB

Answer 4

Application
Network
Classic

Question 5

What does the network load balancer do?

Answer 5

Distributes traffic within the AWS environment only.

Question 6

To distribute HTTP and HTTPS requests, what load balancer is required?

Answer 6

Application Load Balancer

Question 7

Are ELBs to be considered highly available?

Answer 7

Yes

Question 8

Explain the ELB Component: Listeners

Answer 8

Defines how inbound connections are routes.

Question 9

Explain the ELB Component: target groups

Answer 9

A group of resources to which you want to route your requests.

Question 10

Explain the ELB Component: rules

Answer 10

Rules are associated with each listener. And help determine behaviour if certain criteria are met.

Question 11

Explain the ELB Component: Healthchecks

Answer 11

Checks a target resource group / resource is healthy.

If it’s not. Actions can be specified.

Question 12

True or false. You must have a ELB mode, in each AZ you want an ELB to distribute traffic to?

Answer 12

True

Question 13

What does cross zone load balancing do, in relation to ELBs.

Answer 13

Ensures all targets, in al AZ’s get an equal load.

Question 14

What does a ELB Launch config do?

Answer 14

Allows you to specify setting and details of the EC2’s you want the ELB to launch.

Question 15

Does ELB have the power to take over encryption and decryption work from EC2 instances, and manage it centrally at the load balancer?

Answer 15

No!

Question 16

Can EC2 auto scaling launch templates, deploy multiple instance types and purchase types in one group?

Answer 16

Yes

Question 17

Can you change the health of an instance using auto scaling commands?

Answer 17

Yes

Question 18

What’s the default TTL for a DNS entry in ELB

Answer 18

60 seconds

Question 19

What determines the cost of an application load balancer

Answer 19

Load Capcity Units

each hour or partial hour the ELB runs

Question 20

What does LCU mean?

Answer 20

Load capacity Units

Question 21

Do you need multiple load balancers for HA?

Answer 21

No

Question 22

Your load balancer and EC2 instances should always be in separate security groups. True or false?

Answer 22

True

Question 23

It is considered best practise for servers behind a load balancer, to only be accessible by the load balancer. Yes or no?

Answer 23

Yes

Question 24

True or false. NAT instanced should always be used in public subnets?

Answer 24

True

Question 25

What is a cool down period?

Answer 25

It prevents auto scaling groups launching or terminating instances before their effect is visible.

Question 26

What’s a target tracking scaling policy?

Answer 26

Increase or decrease current capacity of the group based on a target value for a specific metric.

Question 27

A target tracking scaling policy can scale when a metric hits a certain target. Can it scale out if the metric is below target value too?

Answer 27

No

Question 28

You want to keep average aggregate CPU at 40% within your scaling group. What scaling policy to use?

Answer 28

Target scaling

Question 29

Can you specify a cool down period in step scaling policies?

Answer 29

No

Question 30

Define step scaling

Answer 30

Increase or decrease the current capacity of a scaling group based on “step adjustments” - these adjustments vary based on the size of the alarm breach.

Question 31

What scaling policy is comparable to a thermostat? You set the target, the thermostat does all the work.

Answer 31

Target scaling

Question 32

Define simple scaling

Answer 32

Increase or decrease the current capacity of a group based on a single scaling adjustment.

Question 33

In an auto scaling group. What does auto scaling launch config specify

Answer 33

Instance type and AMI

Question 34

Can you attatch multiple scaling policies to an auto scaling group?

Answer 34

Yes

Question 35

By default, is detailed logging enabled for auto scaling groups?

Answer 35

Yes