Access modes (ReadWriteOnce, ReadOnlyMany, ReadWriteMany) in Kubernetes - Mini Project: Build & Apply

Understanding Kubernetes Persistent Volume Access Modes

📖 Scenario: You are setting up storage for a Kubernetes application. You need to understand how different access modes control how pods can use the storage.Access modes define if the storage can be read or written by one or many pods at the same time.

🎯 Goal: Learn to create a PersistentVolumeClaim (PVC) with different access modes: ReadWriteOnce, ReadOnlyMany, and ReadWriteMany.You will write YAML snippets to define PVCs with these access modes and see how they affect pod access.

📋 What You'll Learn

Create a PersistentVolumeClaim YAML with ReadWriteOnce access mode

Add a PVC YAML with ReadOnlyMany access mode

Create a PVC YAML with ReadWriteMany access mode

Print the access modes of each PVC to verify

💡 Why This Matters

🌍 Real World

Kubernetes applications often need persistent storage. Understanding access modes helps ensure data is shared correctly and safely among pods.

💼 Career

DevOps engineers and Kubernetes administrators must configure storage access modes to meet application requirements and avoid data corruption.

1

Create a PersistentVolumeClaim with ReadWriteOnce access mode

Create a YAML string variable called pvc_rwo that defines a PersistentVolumeClaim with accessModes set to ["ReadWriteOnce"]. Use storage: 1Gi under resources.requests.

Kubernetes

# Create pvc_rwo YAML string with accessModes: ["ReadWriteOnce"] and storage 1Gi
# Your code here

Need a hint?

Remember to use a multi-line string with triple quotes and indent YAML properly.

2

Add a PersistentVolumeClaim with ReadOnlyMany access mode

Create a YAML string variable called pvc_rom that defines a PersistentVolumeClaim with accessModes set to ["ReadOnlyMany"]. Use storage: 2Gi under resources.requests.

Kubernetes

pvc_rwo = """
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-rwo
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
"""
# Create pvc_rom YAML string with accessModes: ["ReadOnlyMany"] and storage 2Gi
# Your code here

Need a hint?

Follow the same YAML structure as the first PVC but change the access mode and storage size.

3

Create a PersistentVolumeClaim with ReadWriteMany access mode

Create a YAML string variable called pvc_rwm that defines a PersistentVolumeClaim with accessModes set to ["ReadWriteMany"]. Use storage: 3Gi under resources.requests.

Kubernetes

pvc_rwo = """
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-rwo
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
"""

pvc_rom = """
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-rom
spec:
  accessModes:
    - ReadOnlyMany
  resources:
    requests:
      storage: 2Gi
"""
# Create pvc_rwm YAML string with accessModes: ["ReadWriteMany"] and storage 3Gi
# Your code here

Need a hint?

Use the same pattern as before but set accessModes to ReadWriteMany and storage to 3Gi.

4

Print the access modes of each PersistentVolumeClaim

Write three print statements to display the access modes of pvc_rwo, pvc_rom, and pvc_rwm. Extract the access mode line from each YAML string and print it exactly as Access mode: ReadWriteOnce, Access mode: ReadOnlyMany, and Access mode: ReadWriteMany respectively.

Kubernetes

pvc_rwo = """
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-rwo
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
"""

pvc_rom = """
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-rom
spec:
  accessModes:
    - ReadOnlyMany
  resources:
    requests:
      storage: 2Gi
"""

pvc_rwm = """
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-rwm
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 3Gi
"""
# Print the access modes of pvc_rwo, pvc_rom, and pvc_rwm
# Your code here

Need a hint?

Print the exact lines as shown, one per PVC.