Understanding Kubernetes Storage: From Zero to Writing a CSI Driver

Session presented at Big Mountain Data and Dev Conference(www.utahgeekevents.com)

Speakers:Gerry Seidman

Level:Intermediate

Track:Gerry Seidman

Room:Room 4

Description:Understanding the many Kubernetes storage ‘objects’ along with their not-always-obvious interactions and life-cycles can be daunting (Volumes, Persistent Volumes, Persistent Volume Claims, Volume Attachments, Storage Classes, Volume Snapshots, CSIDriver, CSINode, oh my).
One way to get a deep understanding of these storage objects work and how storage-related scheduling works in Kubernetes is to write a Container Storage Initiative (CSI) driver. Of course, most of us will never need to write a CSI driver, in this session the speaker will help you get a deep understanding of Kubernetes storage from what he gleaned from writing a CSI driver. This inside-out will make clear what each Kubernetes Storage objects does and how it fits in with the scheduling of Pods across the nodes in a Kubernetes cluster. This level of understanding provides valuable insight for developer and devOps people when designing, managing and debugging applications deployed in Kubernetes clusters.
From this session you will obtain an understanding of:
• The Kubernetes Declarative Model
• The many Kubernetes Storage Objects
• How Kubernetes volumes are associated with mounted storage available from within containers
• Kubernetes StatefulSets and templated Persistent Volume Claims
• What happens with persistent storage as StatefulSets are scaled up/down
• Kubernetes Scheduling and how it is influenced by storage object
• How Kubernetes controllers move the various storage objects through their life-cycles
• What is the role and responsibility of a storage type specific CSI Driver
• What are the roles and responsibilities of CSI support ‘Side-Cars’
• Why/how CSI drivers are used to allocate Ephemeral volumes in addition to Persistent Volumes
• Putting it all together and relating this all back to how a CSI Driver help make this all work.