DevOps Classroom Series – 22/Nov/2020

K8s Volume Snapshots & Clones

• K8s Volumesnapshot represents the snapshot of volume on storage system.
• Source can be specified as PVC Refer Here
• CSI Volume Cloning feature add support for existing PVCs to clone the volume. Refer Here

K8s Controller – StatefulSet

• Stateful sets are used to stateful replicas Refer Here

K8s Controller – DaemonSet

• Daemonsets are used to manage creation of a Particular Pod on all or selected nodes in k8s cluster
• Usecases:
  • Logging agent
  • Montioring agent
• Apply the spec Refer Here

K8S Deployments

• Deployment is a k8s object that acts as a wrapper around ReplicaSet and makes it easier to use.
• The major reason for Deployment is
  • it maintains the history of revisions (i.e. history of your application Deployments)
  • it makes it easy to roll back to previous revisions
  • it gives a way to do zero down time deployments
• Deployment Strategy:
  • Rolling Update:
    • This give an option to deploy your application without having downtime
    • This gives maxUnavailable, maxSurge
  • Recreate:
    • This option kills all the running pods and recreates new pods
• Refer Here for deployment commands
• Now lets write a sample deployment Refer Here
• Follow the complete application creation in k8s Refer Here