Checking Kubernetes storage status

The PowerAI Vision application requires disk storage for activities including data set storage. The disk space requirements are described using Kubernetes Persistent Volume configuration. The kubectl command can be used to examine the pv (PersistentVolume) and pvc (PersistentVolumeClaims) resources.

Note: The storage requirements described in the PersistentVolume and PersistentVolumeClaims are not enforced in the standalone deployment. Therefore, the requested space might not be available in the underlying storage of the system. See Disk space requirements for information about product storage requirements.

Using kubectl get pv and pvc commands
Using the kubectl describe pv command
Using the kubectl describe pvc command

Using kubectl get pv and pvc commands

The kubectl get pv and kubectl get pvc commands can be used to see what PersistentVolume and PersistentVolumeClaim have been defined for the application.

Example output

# /opt/powerai-vision/bin/kubectl.sh get pv
NAME                  CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS    CLAIM                             STORAGECLASS   REASON    AGE
powerai-vision-data   40Gi       RWX            Retain           Bound     default/powerai-vision-data-pvc                            48d
# /opt/powerai-vision/bin/kubectl.sh get pvc
NAME                      STATUS    VOLUME                CAPACITY   ACCESS MODES   STORAGECLASS   AGE
powerai-vision-data-pvc   Bound     powerai-vision-data   40Gi       RWX                           48d

Interpreting the output

The above output shows information about the Persistent Volume and Persistent Volume Claim for PowerAI Vision. The application currently has a capacity claim of 40G and it is successfully "Bound". If the STATUS is not "Bound", the application does not have access to the necessary storage.

Using the kubectl describe pv command

The kubectl describe pv command is used to see detailed information about the Persistent Volume used by the application.

Example output

# /opt/powerai-vision/bin/kubectl.sh describe pv
NAME                  CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS    CLAIM                             STORAGECLASS   REASON    AGE
powerai-vision-data   40Gi       RWX            Retain           Bound     default/powerai-vision-data-pvc                            48d
[root@dlf01 ~]# /opt/powerai-vision/bin/kubectl.sh describe pv
Name:            powerai-vision-data
Labels:          assign-to=powerai-vision-data
                 type=local
Annotations:     pv.kubernetes.io/bound-by-controller=yes
StorageClass:    
Status:          Bound
Claim:           default/powerai-vision-data-pvc
Reclaim Policy:  Retain
Access Modes:    RWX
Capacity:        40Gi
Message:         
Source:
    Type:  HostPath (bare host directory volume)
    Path:  /opt/powerai-vision/volume/
Events:    <none>

Interpreting the output

The above output shows more details about the Persistent Volume used by the application. The Sourcesection has the critical configuration values for Type and Path. The Events section will have information about Error events if there were issues with the Persistent Volume.

Using the kubectl describe pvc command

The kubectl describe pvc command is used to see detailed information about the Persistent Volume Claim for the application.

Example output

[root@dlf01 ~]# /opt/powerai-vision/bin/kubectl.sh describe pvc

Name:          powerai-vision-data-pvc
Namespace:     default
StorageClass:  
Status:        Bound
Volume:        powerai-vision-data
Labels:        app=powerai-vision
               chart=ibm-powerai-vision-prod-1.1.0
               heritage=Tiller
               release=vision
Annotations:   pv.kubernetes.io/bind-completed=yes
               pv.kubernetes.io/bound-by-controller=yes
Capacity:      40Gi
Access Modes:  RWX
Events:        <none>

Interpreting the output

The above output shows more details about the Persistent Volume Claim used by the application. The Volume section references the underlying Persistent Volume, and the Status should be "Bound" if it has been successfully allocated to the application. The Events section will show if there were issues with the Persistent Volume Claim.