High Availability and Scaling

Question 1

automatically distributes your incoming traffic across multiple targets, such as EC2 instances, containers, and IP addresses, in one or more Availability Zones.

Answer 1

Elastic Load Balancer

Question 2

First load balancer that is now out of date and not recommended

Answer 2

Classic Load Balancer (CLB)

Question 3

Load balancer functions at layer 7 of OSI model, Supports HTTP/S/WebSocket

Answer 3

Application Load Balancer (ALB)

Question 4

Load balancer functions at the fourth layer of the Open Systems Interconnection (OSI) model. It can handle millions of requests per second. Supports TCP, TLS, UDP

Answer 4

Network Load Balancer (NLB)

Question 5

Each ELB is configured with an A record which points to the ELB nodes placed across the chosen AZs.

Answer 5

True

Question 6

ELB Nodes with public IPs AND private IPs

Answer 6

Internet-Facing

Question 7

ELB Nodes with private IP

Answer 7

Internal-Facing

Question 8

Controls what protocols and ports will be accepted by the ELB nodes

Answer 8

Listeners

Question 9

Can an internet-facing ELB connect to both public and private EC2 instances?

Answer 9

Yes

Question 10

Suggested size by AWS of IP’s for ELBs in order for scale

Answer 10

/27 or larger

Question 11

Ability to distribute or load balance across all instances in all AZ

Answer 11

Cross-Zone Load Balancing

Question 12

Will nodes scale automatically if the load increases?

Answer 12

Yes

Question 13

Are CLB capable of scaling?

Answer 13

No

Question 14

ALB must have SSL certifications installed if HTTPS is used

Answer 14

True

Question 15

Are ALB slower than NLB?

Answer 15

Yes

Question 16

Direct the connections which arrive at a listener in an ALB

Answer 16

Rules

Question 17

Forwarding encrypted connections without terminating them requires Network Load balancer

Answer 17

True

Question 18

Can you detailed health checking with a network load balancer?

Answer 18

No

Question 19

Can NLB have static IPs for whitelisting?

Answer 19

Yes

Question 20

Can NLB forward TCP to instances with unbroken encryption

Answer 20

Yes

Question 21

NLB are used with privatelink to provide services to other VPCs

Answer 21

True

Question 22

Specifies instance configuration information that can be used to easily provision instances in the same configuration

Answer 22

Launch Templates

Question 23

Used for automatic scaling and self-healing for Ec2 using launch templates/configurations

Answer 23

Auto Scaling Groups

Question 24

Keeps running instances at the desired capacity by provisioning or termination instances

Answer 24

Auto Scaling Groups

Question 25

Updates the capacity based on certain criteria/metrics

Answer 25

Scaling Policies

Question 26

Manually adjust desired capacity

Answer 26

Manual Scaling

Question 27

Time based scaling used for known periods of usage

Answer 27

Scheduled Scaling

Question 28

Scale out or in based on a metric reaching an alarm state (ex. cpu usage, i/o)

Answer 28

Simple Scaling

Question 29

Scaling similar to Simple scaling but the adjustments vary based on the size of the alarm breach, add more control of scaling

Answer 29

Stepped Scaling

Question 30

Scaling where you set a target value that represents the ideal average utilization or throughput level for your application and the scaling group adds or removes resources to maintain the desired level

Answer 30

Target Tracking

Question 31

How long to wait on a scaling action before performing another (default 300 seconds)

Answer 31

Cooldown period

Question 32

Are auto scaling groups free?

Answer 32

Yes only charged for the resources

Question 33

Are scaling policies required when creating an Auto Scaling Group

Answer 33

No

Question 34

Create solutions that are aware of events in the Auto Scaling instance lifecycle, and then perform a custom action on instances when the corresponding event occurs

Answer 34

ASG Lifecycle Hooks

Question 35

Used ensure that your bootstrap scripts have completed successfully and the applications on the instances are ready to accept traffic

Answer 35

ASG Lifecycle Hooks

Question 36

uses the results of the Amazon EC2 instance status checks and system status checks to determine the health status of an instance

Answer 36

EC2 Health Check

Question 37

Checks whether the load balancer reports the instance as healthy, confirming whether the instance is available to handle requests

Answer 37

ELB Health Check

Question 38

health checks by using a combination of custom health checks, Amazon EC2 status checks, and Elastic Load Balancing health checks, if enabled

Answer 38

Custom Health Check

Question 39

Delay before starting Health Checks (default 300 seconds)

Answer 39

Grace Period

Question 40

SSL load balancer sits on the edge and grabs all incoming HTTPS traffic. After decryption, the balancer encrypts again and passes it to the server. Every EC2 instance on the backend needs to perform cryptographic operations

Answer 40

SSL Bridging

Question 41

Network Load Balancer just passes the connection to one of the backend instances, performs no encryption or decryption

Answer 41

SSL Passthrough

Question 42

Listener configured for HTTPS, ELB needs an SSL certificate for decryption but doesn’t encrypt data passed to the EC2 instances

Answer 42

SSL Offload

Question 43

Feature to enable the load balancer to bind a user’s session to a specific target. This ensures that all requests from the user during the session are sent to the same target.

Answer 43

Session Stickiness

Question 44

Used for running and scaling 3rd party appliances and provide network security at scale

Answer 44

Gateway Load Balancer