Placement Group Strategies

Question 1

Cluster Strategy

Answer 1

• Same rack
• Same AZ

Uses:

• big data job that needs to complete fast
• application that needs low latency and high network throughput

Question 2

Cluster Strategy pros

Answer 2

• Low latency
• High performance
• Good Network

Question 3

Cluster Strategy cons

Answer 3

High risk - if the rack fails, all instances fail at the same time

Question 4

Spread Strategy

Answer 4

• placed on distinct racks, with each rack having its own network and power source
• located on different hardware
• can span multiple AZs

Use case:

• application that needs to maximise high availability
• critical applications where each instance must be isolated from failure from each other

Question 5

Spread Strategy pros

Answer 5

• Instances located on different hardware
• Minimise risk of failure
• Can span across Availability zones

Question 6

Spread Strategy cons

Answer 6

Con: max 7 instances per group, per AZ

Question 7

Partition Strategy

Answer 7

each partition has its own set of racks. Each rack has its own network and power source

allows isolating the impact of hardware failure within your application

Question 8

Partition Strategy pros

Answer 8

• up to 7 partitions per AZ
• each partition represents a rack - safe from a rack failure
• Up to 100s of EC2 instances
• A partition failure can affect many EC2s but not other partitions

Question 9

Partition Strategy cons