Section6: EC2

Question 1

What is Elastic IP?

Answer 1

-It is static/fix public IP address.

• Can be found in the AWS console if you goto “EC2”->”Elastic IP”

Question 2

What is Placement Groups?

Answer 2

• Sometimes you want to control over the EC2 Instance placement strategy.
• When you create a placement group, you specify one of the following strategies for the group:
  - Cluster - clusters instances into low-latency group in a single Availability Zone.
  - Spread - spreads instances acrosss underlying(different) hardware
  - Partition - spreads instances across many different partitions(Different sets of racks)

Question 3

Explain the use case, pros and cons for “Placement Groups Cluster”

Answer 3

• Its on the same rack
• Pros: Great network speed
• Cons: If the rack fails, all instances fails at the same time.
• Use case:
  - Big Data job that needs to complete fast
  - Application that needs extremely low latency.

Question 4

Explain the use case, pros and cons for “Placement Groups Spread”

Answer 4

Pros:
- All instance are located on different racks/hardware.
- Reduce risk of simultaneous failure
- Can span across Availability zones

Cons:
- limited to 7 instances per AZ(Availability Zones) per placement group

Use case:
- Application that needs high availability
- Critical Application that each instance must be isolated from failure from each other.

Question 5

Explain “Placement Groups Partition”

Answer 5

• Up to 7 partitions per AZ(Available Zones)
• Can span across multiple AZs in the same region
• The instances in a partition do not share racks with the instances in the other partitions.
• A partition failure can affect many EC2 but wont affect other partitions.

Question 6

What is EC2 Hibernate? p53

Answer 6

• The in-memory(RAM) state is preserved, it is stored to a file which gets encrypted.
• The instance boot is much faster.
• Doesnt support all instances
• Instance RAM size must be less than 150GB.

-Use Cases:
- long running processing
- saving the RAM state
- services that take time to initialize

Question 7

What is EC2 Nitro?

Answer 7

• Next generation of EC2 instances with new virtualization technology.
• Allows for better performance:
  - Better networking options
  - Higher speed EBS
• Better underlying security

Question 8

What is vCPU?

Answer 8

• Take the number of core’s times the number of threads per CPU. Example 4 core and 2 threads per core gives you 8 vCPU’s.