As can be seen in the diagram above, the same persistent volume (pv) is shared across the desktop-online, platform and EC pod(s). This is achieved by referencing a single persistent volume claim (pvc).
Hint!
If you are unfamiliar with how persistent volumes work in Kubernetes, please refer to the official documentation on https://kubernetes.io/docs/concepts/storage/persistent-volumes/.
The following table describes what gets stored where on the persistent volume:
Path within pod | Description |
|---|---|
/opt/mz/persistent/3pp | This is where additional 3pp jar files needed for Usage Engine are stored. |
/opt/mz/persistent/jni | This is where jni files are stored. Example: SAP RFC native library will be stored here. |
/opt/mz/persistent/log | This is where the desktop-online, platform and EC pod logs are stored. |
/opt/mz/persistent/backup | This is where the backup of your configurations will be stored in zip format. |
/opt/mz/persistent/keys | Disk based keystore is a deprecated feature. Please refer to https://infozone.atlassian.net/wiki/spaces/UEPE4D/pages/161481567/Common+Preparations#TLS-%5BinlineExtension%5D for information about how to do this in the preferred way. |
/opt/mz/persistent/storage | This is where the database file gets stored when using Derby as system database. |
You are free to create whatever additional files/directories under /opt/mz/persistent that your use case may require.
If you, for for example, need to share data between the platform and EC pod(s), you can create a directory /opt/mz/persistent/data and use that to exchange information.
Configuration
Usage Engine Private Edition can be configured to reference an arbitrary persistent volume claim by setting the following helm values:persistence: enabled: true existingClaim: my-pvc
In this example, my-pvc is an arbitrary persistent volume claim that you have created beforehand.