Section 6 - 8

Question 1

T/F - Elastic Network Interface (ENI) can be attached to EC2 instances in another AZ.

Answer 1

False. ENIs are bound to a specific AZ and cannot be attached to EC2 instances outside of that AZ

Question 2

The io1/io2 family of EBS volumes can use EBS multi-attach. How many instances can be attached to a single EBS volume at a time?

Answer 2

16 instances

Question 3

T/F - EFS is only compatible with Windows based AMIs

Answer 3

False. EFS is only compatible with Linux based AMIs

Question 4

You are running a high-performance database that requires an IOPS of 310,000 for its underlying storage. What do you recommend?

Answer 4

EC2 Instance Store

Question 5

You are running a website on 10 EC2 instances fronted by an Elastic Load Balancer. Your users are complaining about the fact that the website always asks them to re-authenticate when they are moving between website pages. You are puzzled because it’s working just fine on your machine and in the Dev environment with 1 EC2 instance. What could be the reason?

Answer 5

You need to enable Sticky Sessions to ensure that the clients traffic is always redirecting to the same target (in this case the EC2 instance).

Essentially the client is getting sent to other EC2 instances by the load balancer while they’re navigating the website.

Question 6

Your website is using an ALB to distribute traffic to your EC2 instances. You website only sees the traffic coming from your own ALBs private IPv4 addresses. If you modify your websites backend, where can you request the clients IP address from?

Answer 6

The X-Forwarded-For header

Question 7

T/F - ALB does not support the TCP protocol

Answer 7

True, ALB supports HTTP/HTTPS, and WebSocket

Question 8

T/F - ALBs can route traffic to different Target Groups based on URL Path, Hostname, HTTP Headers, and Query Strings.

Answer 8

True

Question 9

T/F - ALBs can route traffic to different Target Groups based on the clients geographical location

Answer 9

False, do not confuse an ALB with Route 53

Question 10

T/F - An ALB can have an NLB as its target group

Answer 10

False, an ALB cannot route traffic to a lower level in the OSI model (it would be going backwards)

Question 11

T/F - An NLB can have an ALB as its target group

Answer 11

True, since an NLB operates at a lower layer, it can use an ALB as a target group

Question 12

You need a fixed static IP address for your end-users. What type of Elastic Load Balancer would you use?

Answer 12

Network Load Balancer, ALBs do not have a static IP

Question 13

T/F - Both NLBs and ALBs have a static DNS name

Answer 13

True

Question 14

T/F - Network Load Balancer has 1 static IP address per AZ

Answer 14

True

Question 15

Which ELB can you attach a Elastic IP address to?

Answer 15

An NLB, ALBs cannot have Elastic Ip addresses

Question 16

You have an ALB that is configured to redirect traffic to 3 Target Groups with these hostnames: users.example.com, api.external.example.com, and checkout.example.com.

You would like to configure HTTPS for each of these hostnames. How do you configure the ALB to make this work?

Answer 16

Use Server Name Indication (SNI)

Question 17

How does SNI work?

Answer 17

It loads multiple SSL certificates on to 1 web server, to serve multiple pages

Question 18

In your ASG you set both “desired” and “maximum” capacity to 3. You set up CloudWatch to scale out your ASG when CPU utilization reaches 60%. What happens to the desired/max capacity when CPU utilization reaches 60%?

Answer 18

Absolutely nothing. Maximum obviously stays the same, and Desired cannot go higher than maximum.

Question 19

You have an Auto Scaling Group fronted by an Application Load Balancer. You have configured the ASG to use ALB Health Checks, then one EC2 instance has just been reported unhealthy. What will happen to the EC2 instance?

Answer 19

The ASG will terminate the instance

Question 20

Which protocols are supported in NLB Health Checks?

Answer 20

TCP, HTTP, and HTTPS