kubernetes tutorial | Scheduling Pods to Nodes | Node Affinity | Demo

*Certified Kubernetes Administrator*
------------------------------------------------------------
kubernetes tutorial | Scheduling Pods to Nodes | Node Affinity | Demo

*Description*
----------------------

In this video, you are going to learn the concepts of Scheduling pods to nodes using Node Affinity and we are also going to see a demo on the same as well.

*Kubernetes - Scheduling Pods to Nodes using NodeAffinity*
---------------------------------------------------------------------------------------------------

1. Scheduling Pods to Nodes using “Node Affinity”
2. Scheduling Pods to Nodes Using Labels
3. Recap - NodeSelector
4. Node Affinity
5. Types of Node Affinity
6. Use Cases
7. DEMO: Scheduling Pods to Nodes using “Node Affinity”
8. Thank you

For suggestions/feedback/doubts contact
email: [email protected]

Happy Learning !!!

========================================================================================

*USEFUL LINKS*
----------------------------

*Assigning Pods to Nodes*

_https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/_

*Assigning Pods to Nodes using Node Affinity*

_https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node #node-affinity_

*API References*

_https://kubernetes.io/docs/reference/kubernetes-api/_

*Kubectl Command Reference*

_https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands_

==========================================================================================
#vsparkz #kubernetes #k8s #containers


*DEMO STEPS*
-------------------------

*Step 1: Access & Inspect the Kubernetes Cluster*

$ kubectl cluster-info

$ kubectl get nodes

$ kubectl get pods -n kube-system

*Step 2: Add custom labels to the Nodes*

$ kubectl label nodes worker01.vsparkz.com webserver=nginx workertype=python size=small

$ kubectl label nodes worker02.vsparkz.com webserver=apache workertype=python size=large

*Step 3: Create & Schedule a Pod using “Required” Affinity Type*

$ kubectl run nginx --image=nginx --dry-run=client -o yaml

Copy the output content and create a file - schedule_using_required.yaml

$ vi schedule_using_required.yaml

_______________________________________________________
apiVersion: v1
kind: Pod
metadata:
name: nginx
spec:
containers:
- image: nginx
name: nginx
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: webserver
operator: In
values:
- nginx
_______________________________________________________



$ kubectl apply -f schedule_using_required.yaml

$ kubectl get pods -o wide


*Step 4: Create & Schedule a Pod using “Preferred” Affinity Type*

$ vi schedule_using_preferred.yaml

_______________________________________________________
apiVersion: v1
kind: Pod
metadata:
name: nginx
spec:
containers:
- image: nginx
name: nginx
affinity:
nodeAffinity:
preferredDuringSchedulingIgnoredDuringExecution:
- weight: 10
preference:
matchExpressions:
- key: size
operator: In
values:
- large
_______________________________________________________

$ kubectl apply -f schedule_using_preferred.yaml


*Step 5: Create & Schedule a Pod using both “required” & “preferred” Affinity Type*

$ vi schedule_using_both.yaml

_______________________________________________________
apiVersion: v1
kind: Pod
metadata:
name: nginx
spec:
containers:
- image: nginx
name: nginx
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: workertype
operator: In
values:
- python
preferredDuringSchedulingIgnoredDuringExecution:
- weight: 20
preference:
matchExpressions:
- key: size
operator: In
values:
- large
_______________________________________________________

$ kubectl apply -f schedule_using_both.yaml

$ kubectl get pods -o wide

========================================================================================================================