Chapter 9. ReplicaSets

Question 1

Why do we want to use replicas ?

Answer 1

Redundancy
Multiple running instances mean failure can be tolerated.

Scale
Multiple running instances mean that more requests can be handled.

Sharding
Different replicas can handle different parts of a computation in parallel.

Question 2

What is a replicaSet ?

Answer 2

A ReplicaSet acts as a cluster-wide Pod manager, ensuring that the right types and number of Pods are running at all times.

Question 3

What is a reconciliation loop ?

Answer 3

The actual act of managing the replicated Pods

Question 4

Command to scale replicas ?

Answer 4

kubectl scale replicasets kuard –replicas=4

Question 5

How can you scale replicas based on cpu usage ?

Answer 5

kubectl autoscale rs kuard –min=2 –max=5 –cpu-percent=80

Question 6

How do you delete a replicaSet ?

Answer 6

kubectl delete rs kuard

Question 7

How can you delete only the replicaSet and not the Pods ?

Answer 7

kubectl delete rs kuard –cascade=false