Using container image pruning
Container image pruning on the SC//Reliant™ platform schedules the automatic removal of unused container images. As image versions and tags accumulate on a node over time, this keeps local disk usage healthy without manual cleanup.
This page describes the Image Pruning parameter and the procedures for enabling and disabling pruning on a node group.
Considerations
- Pruning removes container images that are not currently in use by a running container. Images backing currently running containers are not removed.
- Disabling Image Pruning stops the scheduled removal job. Existing unused images will not be automatically cleaned up until pruning is re-enabled.
Parameters
| Property | Description | Example |
|---|---|---|
| Cron Entry | Defines how frequently the pruning job runs, expressed as a standard cron expression. | 0 0 * * * (runs every day at midnight) |
For a quick reference of common cron expressions, see the cron expression reference on the Image Management overview.
Enabling Image Pruning
- Navigate to the node group Hash configuration page.
- Locate the Image Pruning section.
- Click the Enable this option toggle in the top-right corner of the Image Pruning panel so that it turns blue/on.
- In the Cron Entry text field, enter a valid cron expression to define the pruning schedule. For example,
0 0 * * *prunes every day at midnight. - Save the configuration using the page's save/apply action.
Disabling Image Pruning
- Navigate to the node group Hash configuration page.
- Locate the Image Pruning section.
- Click the Enable this option toggle in the top-right corner of the Image Pruning panel so that it turns gray/off.
- Save the configuration using the page's save/apply action.
Note: Disabling Image Pruning stops scheduled removal jobs. Existing unused images will not be automatically cleaned up until pruning is re-enabled.