Completek8s Classroomnotes 15/Sep/2023

Kubernetes Workloads

Activity 1: Create a Replica Set for nopCommerce

• Lets create a replicaset for nopCommerce shaikkhajaibrahim/nopcommerceaug23 and a service with cluster ip and some external accessibility like nodeport
  
• Refer Here for the changes committed
• Now apply the changes by using following commands

 kubectl apply -f activity1/
 kubectl config set-context --current --namespace=activity1
 kubectl get svc
 kubectl get rs

* Now we need to patch a node in k8s cluster. As an admin you are expected to cordon and drain
* Safely brining down a node
* Lets mark the node cordon for k8s cluster to stop scheduling workloads on node

kubectl cordon node-2

* Now drain by ignoring daemonsets

 kubectl drain --ignore-daemonsets node-2

* Do your patching
* Uncordon the node

kubectl uncordon node-2

• Lets say we have 10 pods in replicaset running and we always need atleast 80% to be running for better customer experience. Now in these situations how to handle maintenenance

Pod Disruption Budget

• Refer Here for the changes done to configure 80% minimum availability for replicas in the case of disruptions
  

Scenario

• We need to put restriction on namespace to restrict how many pvc claims, loadbalancers, nodeports
• We have ResourceQuota Object
• Refer Here for ResourceQuota
• Lets apply a resource quota to number of services < 2, nodeports < 2 and pods < 10
• Refer Here for the changes
• Apply all the manifests and check for status of quotas
  
  
• In this the number of pods cannot exceed 10 due to quota