Persistent Volume Types in Kubernetes

1. hostPath

• Description: Maps a file or directory on the host node filesystem into the Pod.

• Use Case: Testing & development with Minikube or single-node clusters.

• Limitations:

  • Not suitable for multi-node clusters.
  • Not portable between nodes.

hostPath:
  path: /mnt/data

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2. nfs (Network File System)

• Description: Mounts an external NFS share into the cluster.

• Use Case:

  • Shared storage across Pods and nodes.
  • Use cases where multiple Pods need to read/write the same files (e.g., media servers, file storage).

• Pros:

  • Mature, POSIX-compliant shared filesystem.

• Cons:

  • Requires an external NFS server setup.

nfs:
  server: 10.10.10.10
  path: /data

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3. gcePersistentDisk (GCP)

• Description: Mounts a Google Cloud Persistent Disk into a Pod.

• Use Case: Durable block storage in GKE clusters.

• Supports:

  • ReadWriteOnce, ReadOnlyMany

gcePersistentDisk:
  pdName: my-disk
  fsType: ext4

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4. awsElasticBlockStore (EBS)

• Description: Mounts an EBS volume in AWS to a Pod.
• Use Case: Stateful apps in EKS.
• Note: Volume must be in the same availability zone as the node.

awsElasticBlockStore:
  volumeID: vol-0abcd1234
  fsType: ext4

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5. azureDisk / azureFile

• azureDisk: Block storage (good for databases).
• azureFile: Shared file storage (good for logs, user uploads).
• Use Case: Use in AKS clusters based on your storage type needs.

azureDisk:
  diskName: mydisk
  diskURI: https://...

azureFile:
  secretName: azure-secret
  shareName: myshare

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6. local

• Description: Mounts a local disk attached to the node.
• Use Case: High-performance workloads like databases where latency is critical.
• Limitation: Pod must run on the same node.

local:
  path: /mnt/disks/ssd1

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8. CSI (Container Storage Interface) – Recommended

• Description: New standard that supports a plug-and-play model for external storage providers.

• Use Case: When you use vendor-managed storage like:

  • NetApp, Portworx, Longhorn, OpenEBS, etc.

• Flexibility: Replaces in-tree plugins for better modularity.