☸ Upgrading the Cluster
☘️ Check the current version of your cluster:
kubectl version
☘️ Check the current version of the Kubernetes control plane:
kubectl version --short
☘️ List the available versions of Kubernetes:
kubectl get nodes
☘️ Upgrade the control plane to a specific version:
sudo kubeadm upgrade plan
sudo kubeadm upgrade apply <version>
☘️ Upgrade the nodes to a specific version:
sudo apt-get update && sudo apt-get upgrade -y
sudo reboot
☘️ Verify that the upgrade was successful:
kubectl get nodes
kubectl get pods --all-namespace
☸ Backing up and Restoring data
☘️ Backup a specific resource:
kubectl get <resource> <resource_name> -o yaml > backup.yaml
For example, to backup a deployment named my-deployment in the default namespace, you would run:
kubectl get deployment my-deployment -n default -o yaml > backup.yaml
☘️ Backup all resources in a namespace
kubectl get all -n <namespace> -o yaml > backup.yaml
For example, to backup all resources in the default namespace, you would run:
kubectl get all -n default -o yaml > backup.yaml
☘️ Restore a specific resource from a backup:
kubectl apply -f backup.yaml
☘️ Restore all resources from a backup:
kubectl apply -f backup.yaml --prune
The --prune flag will remove any resources that are not in the backup.
☘️ Backup and restore persistent volumes:
To backup a persistent volume, you can use your storage provider's tools or utilities such as velero. For example, to backup a persistent volume named my-pv, you would run:
velero backup create my-backup --include-namespaces <namespace> --selector key=value
To restore the persistent volume, you would run:
velero restore create --from-backup my-backup
☸ Scaling the Cluster
☘️ Scale a deployment:
kubectl scale deployment <deployment_name> --replicas=<number_of_replicas>
For example, to scale a deployment named my-deployment to 3 replicas, you would run:
kubectl scale deployment my-deployment --replicas=3
☘️ Scale a statefulset:
kubectl scale statefulset <statefulset_name> --replicas=<number_of_replicas>
For example, to scale a statefulset named my-statefulset to 3 replicas, you would run:
kubectl scale statefulset my-statefulset --replicas=3
☘️ Scale a deployment using autoscaling:
kubectl autoscale deployment <deployment_name> --min=<minimum_number_of_replicas> --max=<maximum_number_of_replicas> --cpu-percent=<cpu_utilization_percentage>
For example, to create an autoscaling deployment named my-deployment with a minimum of 2 replicas, a maximum of 5 replicas, and a target CPU utilization of 80%, you would run:
kubectl autoscale deployment my-deployment --min=2 --max=5 --cpu-percent=80
☘️ Check the current scaling status of a deployment:
kubectl get deployment <deployment_name> -o=jsonpath='{.spec.replicas}'
For example, to check the current scaling status of a deployment named my-deployment, you would run:
kubectl get deployment my-deployment -o=jsonpath='{.spec.replicas}'
Thanks for your attention!!