Persistent data and app updates
App containers can be replaced during updates or redeployment. Persistent volumes store the files and database data that the app recipe is designed to keep.
Persistent files versus container files​
Use the app’s supported file locations. A file written inside an arbitrary directory in the container is not guaranteed to survive replacement. Installing packages manually inside the container is also not a durable customization.
The path shown through SFTP is not necessarily the same path used inside the app container. For example, an SFTP directory called /data represents the recipe’s exposed persistent files; it does not prove that every app stores its data at /app/data internally.
Before changing an image or configuration​
- Read the app’s setup notes and upstream update instructions.
- Confirm where its important files and database live.
- Create a recovery snapshot where available and download a copy.
- Apply the supported change, then check login, saved content and logs.
An update should retain configured persistent data, but an application upgrade can migrate that data into a format an older version cannot use. Reverting only the image is not always a rollback.
For a custom image or unusual mount requirement, ask support to confirm the supported deployment configuration before relying on persistence. Do not assume a Docker command from another platform maps directly to a catalog deployment.