DeamonSet

• A DaemonSet ensures that all (or some) Nodes run a copy of a Pod.
• As nodes are added to the cluster, Pods are added to them. As nodes are removed from the cluster, those Pods are garbage collected.
• Deleting a DaemonSet will clean up the Pods it created.

Typical uses of a DaemonSet

• Running a cluster storage daemon on every node
• Log collection: Running a logs collection daemon on every node
• Monitoring: Running a node monitoring daemon on every node

Commands

k get ds

We can not create ds using the kubectl, so we can

The fastest way to create is to create a deployment

kubectl create deploy nginx --image=nginx --dry-run -o yaml > nginx-ds.yaml

Now replace the line kind: Deployment with kind: DaemonSet in nginx-ds.yaml and remove the line replicas: 1 , strategy {} and status {} as well. Otherwise, it shows error for some required fields like this

error: error validating "nginx-ds.yaml": error validating data: [ValidationError(DaemonSet.spec): unknown field "strategy" in io.k8s.api.apps.v1.DaemonSetSpec, ValidationError(DaemonSet.status): missing required field "currentNumberScheduled" in io.k8s.api.apps.v1.DaemonSetStatus,ValidationError(DaemonSet.status): missing required field "numberMisscheduled" in io.k8s.api.apps.v1.DaemonSetStatus, ValidationError(DaemonSet.status): missing required field "desiredNumberScheduled" in io.k8s.api.apps.v1.DaemonSetStatus, ValidationError(DaemonSet.status): missing required field "numberReady" in io.k8s.api.apps.v1.DaemonSetStatus]; if you choose to ignore these errors, turn validation off with --validate=false