Elastic load Balancing & Auto Scaling Group Section

Question 1

Scalability:

Answer 1

• Scalability mean the application / system can handle greater loads by adapting

Question 2

vertical scalability :

Answer 2

• call center:from junior operator to senior operator
• Increasing the size of the instance
• Common for no distributed systems, like database
• Changing an EC2 Instance Type from a t3a.medium to a t3a.2xlarge is an example of

Question 3

Horizontal scalability

Answer 3

elasticity :

• Increasing the number of instance /system for your application
• Common used for web application/moderm application

Question 4

High Availability:

Answer 4

• Just like horizontal scaling
• Running application / system in last 2 available zones
• Survive a data center loss (disaster)
• What is the main purpose of High Availability in the Cloud? ( application thriving even in case of a disaster)

Question 5

Scalability

Answer 5

• ability to accommodate a lager load by making the hardware stronger (scale up), or by adding nodes (scale out)

Question 6

Elasticity

Answer 6

once as system is scalable, elastic mean that there will be some auto-scaling ,

• so the system can scale based on the load
• pay per use, match demand, optimize costs

Question 7

Agility

Answer 7

• New IT resources are only click away,

- that reduce the time to make those resources available to your developer from week to just minutes

Question 8

What is load balancing

Answer 8

• help be elastic on aws
• Server that forward internet traffic to multiple Ec2 instances downstream
• More user we have, the more it will balance the load across the multiple EC2 instance, all scale on our backend

Question 9

Why use a load balancer?

Answer 9

• Spread load across multiple downstream instance
• Expose a single point of access (DNS) to your application
• Seamlessly handle failures of downstream instances
• Do regular health checks to your instance
• provide SSL termination (HTTPS ) for your website
• High availability across zones

Question 10

Why use an Elastic load Balancer

Answer 10

• EBl is managed load balancer
• distribute traffic across backend EC2 instance, can be Mult-AZ
• support health checks

Question 11

3 type of load balancer

Answer 11

• application LB ( HTTP-L7): Which Load Balancer is best suited for HTTP/HTTPS load balancing traffic
• Network LB (TCP-L4): Which AWS offered Load Balancer should you use to handle hundreds of thousands of connections with low latency?
• Classic LB (old)

Question 12

What an auto scaling group

Answer 12

• Implement elasticity for your application, across multiple AZ
• scale EC2 instance based on the demand on your system, replace unhealthy
• Integrated with the ELB
• What can you use to handle quickly and automatically the changing load on your websites and applications by adding compute resources?
• replace unhealthy instance
• are cost-effective by running at optimal capacity
• automatically register new instances to a load balancer

Question 13

an Auto Scaling Strategy

Answer 13

Which of the following is an Auto Scaling Strategy?

• manual scaling
• dynamic scaling
• predictive scaling
• offers easy horizontal scaling of compute capacity

Question 14

a feature of Load Balancers

Answer 14

• DO regular health check to your instance
• handle failures of downstream instances
• spread load across multiple downstream instance