Set Up Node-Local Storage for dSSM¶

This section describes how to configure node-local storage for distributed Session State Management (dSSM) Pods by creating a Storage Class and a Persistent Volume (PV) for each node. It also explains how to enable persistence in the override file to ensure that database data is retained across pod restarts on the same node.

Create Storage Class and Persistent Volume¶

Follow the steps below to create the required Storage Class and Persistent Volume resources.

Create a local-storage.yaml file with the following content.

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: local-storage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer

Apply the Storage Class.
```
oc apply -f local-storage.yaml
```

Create a local-pv.yaml file for each node where the dSSM database pod will be deployed.

Note: The data will be stored at the path specified in the local.path field of the Persistent Volume. Ensure that this directory exists on the node and has appropriate read/write permissions.

apiVersion: v1
kind: PersistentVolume
metadata:
  name: <your-node-name>-pv
spec:
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteOnce
  storageClassName: local-storage
  local:
    path: /mnt/disks/data-dir
  nodeAffinity:
    required:
      nodeSelectorTerms:
        - matchExpressions:
            - key: kubernetes.io/hostname
              operator: In
              values:
                - <your-node-name>

Apply the Persistent Volume.
```
oc apply -f local-pv.yaml
```

Enable Persistence for dSSM Pods¶

Important:

When persistence is enabled, a Persistent Volume must be defined.
Ensure that the Storage Class and Persistent Volumes are created and correctly bound to the target nodes, as shown in the Create Storage Class and Persistent Volume section.

Follow the steps below to enable persistence for dSSM Pods.

Update the dssm-values.yaml file with the following values.

db:
  persistent_storage: enable
  persistent_storage_gb: 1
  accessMode: ReadWriteOnce
  storage_class_name: local-storage

Run the following command to install the dSSM Helm chart.

helm install f5-dssm tar/f5-dssm-<tag>.tgz -f <over-ride-values>.yaml

For Example:

helm install f5-dssm tar/f5-dssm-1.0.15-0.1.11.tgz -f dssm-values.yaml

Disable Persistence for dSSM Pods¶

Note: When persistence is disabled, Persistent Volume or Storage Class is not required for dSSM pods.

Follow the steps below to disable persistence for dSSM Pods.

In the dssm-values.yaml file, set persistent_storage to disable.
```
db:
  persistent_storage: disbale
```
Run the following command to install the dSSM Helm chart.
```
helm install f5-dssm tar/f5-dssm-<tag>.tgz -f <over-ride-values>.yaml
```
For Example:
```
helm install f5-dssm tar/f5-dssm-1.0.15-0.1.11.tgz -f dssm-values.yaml
```
This configuration disables the use of Persistent Volumes for dSSM pods. As a result, dSSM database data will not be retained across pod restarts.

Feedback

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