Upgrading Data Fabric for Kubernetes

This section describes how to upgrade the plug-in and dynamic provisioner, or upgrade Pods with attached volumes.

Upgrading the Plug-in and Provisioner

Before upgrading the plug-in, stop any Pods using the plug-in. You may want to quiesce any traffic hitting the Pod before shutdown. Failure to shut down the Pods before replacing the plug-in can lead to the Pod not being able to access its data until it is restarted.

Removing the plug-in does not kill existing Pods. The Pods should only lose their mounted storage when a new version of the plug-in is installed and the libraries used to communicate with MapR software are deleted.

Upgrading the provisioner does not require stopping Pods, but dynamic provisioning (creating MapR volumes for new PersistentVolumeClaims) will be unavailable during the provisioner upgrade.

Use these steps to upgrade the plug-in:

  1. Stop any Pods using the the plug-in to be upgraded. Before shutting down the Pod, you might want to quiesce any traffic hitting the Pod.
    NOTE
    If any Pods that use the MapR Data Fabric for Kubernetes are not shut down during the plug-in upgrade, those Pods will have mount access removed and will need to be deleted and re-created as new Pods. If existing Pods need to be removed or are stuck in the Terminating state, you can delete them forcefully by using the kubectl delete pod command:
    kubectl delete pod <pod-name> -n <pod-namespace> --force --grace-period=0
  2. Download the new plug-in. See Downloads (FlexVolume).
  3. Delete the old plug-in:
    kubectl delete -f kdf-<old_plugin>.yaml
  4. Deploy the new plugin:
    kubectl create -f kdf-<new_plugin>.yaml

Upgrading Pods with Attached Volumes

Pods with mounted volumes can be patched in place. See Update API Objects in Place Using kubectl patch. Volumes will disappear only when the Pod is deleted. Patching a Pod does not affect the mount. When a Pod is deleted, a volume disappears. However, if you delete a Pod using a PersistentVolume and you leave the PVC alive, you can remount the PersistentVolumeClaim and its PersistentVolume with a new Pod. In this scenario, there is no disruption or need to recreate the PersistentVolume.