Tweet
Tweet

Slide 1

Slide 1 text

Kubernetes Design Principles: Understand the Why

Slide 2

Slide 2 text

No content

Slide 3

Slide 3 text

No content

Slide 4

Slide 4 text

Node A Node B

Slide 5

Slide 5 text

Node A Node B Container A

Slide 6

Slide 6 text

Node A Node B Container A

Slide 7

Slide 7 text

Kubernetes APIs are declarative rather then imperative.

Slide 8

Slide 8 text

Before: You: System: You: After: You: System:

Slide 9

Slide 9 text

You: System: Master: API Server Node A Node B kubectl create -f replica.yaml

Slide 10

Slide 10 text

You: System: Master: API Server Node A Node B kubectl create -f replica.yaml apiVersion: apps/v1 kind: ReplicaSet metadata: name: frontend spec: replicas: 1 template: metadata: ... spec: ... containers: - name: nginx image: internal.mycorp.com:5000/mycontainer:1.7.9

Slide 11

Slide 11 text

You: System: Master: API Server Node A Node B Pod A definition

Slide 12

Slide 12 text

You: System: Master: API Server Node A Node B Pod A definition Pod A

Slide 13

Slide 13 text

No content

Slide 14

Slide 14 text

Master: API Server Node A Node B Pod A definition Pod A

Slide 15

Slide 15 text

Master: API Server Node A Node B Pod A definition Pod A

Slide 16

Slide 16 text

kubectl create -f replica.yaml Master: API Server Node A Node B Pod A definition

Slide 17

Slide 17 text

Master: API Server Node A Node B Pod A definition

Slide 18

Slide 18 text

Master: API Server Node A Node B Pod A definition Pod A

Slide 19

Slide 19 text

Master: API Server Node A Node B Pod A definition Pod A

Slide 20

Slide 20 text

Master: API Server Node A Node B Pod A definition Pod A

Slide 21

Slide 21 text

The Kubernetes control plane is transparent. There are no hidden internal APIs.

Slide 22

Slide 22 text

Before: Master: Node: Master: After: Master: Node:

Slide 23

Slide 23 text

Master: API Server Node A Node B Master: Scheduler

Slide 24

Slide 24 text

Master: API Server Node A Node B Master: Scheduler kubectl create pod

Slide 25

Slide 25 text

Master: API Server Node A Node B Master: Scheduler Pod A definition

Slide 26

Slide 26 text

Master: API Server Node A Node B Master: Scheduler Pod A definition node: Node B

Slide 27

Slide 27 text

Master: API Server Node A Node B Master: Scheduler Pod A Pod A definition node: Node B

Slide 28

Slide 28 text

Master: API Server Node A Node B Master: Scheduler Pod A Pod A definition node: Node B kubectl delete pod A

Slide 29

Slide 29 text

Master: API Server Node A Node B Master: Scheduler Pod A

Slide 30

Slide 30 text

Master: API Server Node A Node B Master: Scheduler

Slide 31

Slide 31 text

No content

Slide 32

Slide 32 text

No content

Slide 33

Slide 33 text

No content

Slide 34

Slide 34 text

Principle: Obvious solution: Master Node 1 API Server Scheduler Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A node: Node1 Container for pod1 Fetch Secret Object Watch for new Pods

Slide 35

Slide 35 text

Meet the user where they are.

Slide 36

Slide 36 text

Before: After: Master Node 1 API Server Scheduler Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A node: Node1 Container for pod1 Watch for new Pods Secret volume Fetch Secret file

Slide 37

Slide 37 text

No content

Slide 38

Slide 38 text

Master Node 1 API Server Scheduler Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: gcePD1 Fetch Secret Object Watch for new Pods

Slide 39

Slide 39 text

Master Node 1 API Server Scheduler Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: gcePD1 node: Node1 Fetch Secret Object Watch for new Pods Schedule PodA to Node1

Slide 40

Slide 40 text

Master Node 1 API Server Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: gcePD1 node: Node1 Fetch Secret Object A/D Controller Watch for new Pods w/Volumes Storage Backend Attach gcePD1 to Node1

Slide 41

Slide 41 text

Master Node 1 API Server Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: gcePD1 node: Node1 Fetch Secret Object A/D Controller Watch for new Pods w/Volumes Storage Backend Attach gcePD1 to Node1 gcePD1

Slide 42

Slide 42 text

Master Node 1 API Server Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: gcePD1 node: Node1 Fetch Secret Object A/D Controller Watch for new Pods w/Volumes Storage Backend Attach gcePD1 to Node1 gcePD1 Container for pod1 Create container Mount volume

Slide 43

Slide 43 text

Master Node 1 API Server Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: gcePD1 node: Node1 Fetch Secret Object A/D Controller Watch for new Pods w/Volumes Storage Backend Attach gcePD1 to Node1 gcePD1 Container for pod1 Create container Mount volume

Slide 44

Slide 44 text

Workload portability

Slide 45

Slide 45 text

No content

Slide 46

Slide 46 text

Master Node 1 API Server Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: pvc-a node: Node1 Container for pod1 gcePD1 A/D Controller Watch for new Pods w/Volumes Watch state of container pvc-a storage: pv-1 storageClass: storageClass1 pv-1 storage: gcePD1 StorageClass1 storage: gcePD Cluster admin facing API object User facing API object

Slide 47

Slide 47 text

Master Node 1 API Server Kubelet Watch for new Pods, scheduled to this node Docker Daemon Pod A storage: pvc-a node: Node1 Container for pod1 awsEBS1 A/D Controller Watch for new Pods w/Volumes Watch state of container pvc-a storage: pv-1 storageClass: storageClass1 pv-1 storage: awsEBS1 StorageClass1 storage: awsEBS Cluster admin facing API object User facing API object

Slide 48

Slide 48 text

No content

Slide 49

Slide 49 text

No content

Slide 50

Slide 50 text

No content