Volumes

Container Volumes

Container volumes provide persistent or shared storage for application data. A volume maps a directory inside the container to a storage location that can remain available independently of the container lifecycle.

In this article

Volume Overview

Files written only to a container’s writable layer may be lost when the container is redeployed or replaced. Volumes help keep application data outside that temporary layer and make it available after container lifecycle operations.

Persistent application dataStores uploaded files, application content, configuration files or other data that must survive redeployment.
Shared dataAllows multiple containers or nodes to use a common storage location where supported by the environment.
Container path mappingMounts the selected storage location at a defined path inside the container.
Separation from imageKeeps runtime data separate from the container image and application code.
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Store important data outside the temporary container layer

Application data that must remain available after redeployment should be placed in a configured volume or another persistent storage service.

Open Volume Settings

1

Open the environment topology

Create a new environment or open the topology settings of an existing container-based environment.

2

Select the required container layer

Choose the application, service or custom container layer where the storage must be mounted.

3

Open the Volumes section

Expand the container settings and open the Volumes configuration panel.

Container volumes configuration panel
Open the Volumes section for the required container layer.

Add a New Volume

1

Click Add Volume

Use the add control in the Volumes panel to create a new storage mapping.

2

Enter the container path

Specify the directory where the storage should be mounted inside the container.

/var/lib/application/data
3

Select or specify the storage source

Choose the required storage source or mapping option available in the environment configuration.

4

Save the configuration

Confirm the volume entry and apply the topology changes.

Add a container volume
Define the storage source and mount path for the container.
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Use clear and application-specific mount paths

Select a directory that is intended for persistent data and does not overwrite important files included in the container image.

Volume Configuration Types

The exact volume options depend on the platform configuration and container type. Common mappings include persistent storage, shared storage and path-based mounts.

Configuration Purpose Typical use
Persistent volume Keeps data available independently of container replacement or redeployment. Uploads, application data, generated files and persistent configuration.
Shared volume Makes the same storage location available to multiple containers or nodes. Shared media, common assets and clustered application content.
Read-only mount Allows the application to read mounted content without modifying it. Reference configuration, certificates or static shared assets.
Path-based mapping Maps a selected source location to a defined directory inside the container. Custom images that expect data at a specific filesystem path.
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Available options may differ

The storage types and controls visible in the interface can vary according to the hosting provider, environment type and platform version.

Configure Shared Storage

Shared storage is useful when several containers need access to the same files. Configure the same storage source and an appropriate mount path for each required container layer.

1

Create or select the shared storage source

Choose the storage location that will hold the common application data.

2

Mount it in the first container layer

Add the required container path and save the volume mapping.

3

Repeat for additional containers

Use the same shared storage source in each container that requires access to the data.

4

Verify application permissions

Confirm that the container user has the required read or write permission for the mounted directory.

Shared container volume configuration
Use a shared storage source when several containers require the same data.

Edit or Remove a Volume

Existing volume entries can be reviewed from the Volumes panel. Use the available edit control to update a mapping or the remove control to delete it from the topology.

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Check data before removing a volume

Removing a mount from the container can make the application data unavailable. Confirm the data location, dependency and backup status before applying the change.

After changing a volume mapping, apply the environment configuration and verify that the application starts correctly and can access the expected files.

Configuration Recommendations

  • Identify all directories that contain application-generated or user-uploaded data.
  • Do not use temporary container storage for files that must survive redeployment.
  • Use separate volumes for unrelated application data where practical.
  • Confirm ownership and filesystem permissions inside the container.
  • Avoid mounting a volume over a directory that contains required image files unless this is intentional.
  • Back up important data before changing or removing storage mappings.
  • Test volume access after scaling, restart and redeployment operations.
  • Use read-only access where the application does not need to modify mounted content.

Expected Result

The selected storage is mounted at the configured path inside the container. Application data stored in that location remains available according to the selected volume type and can be reused after supported container lifecycle operations.

Important Notes

  • The mount path must use a valid absolute directory inside the container.
  • Volume availability depends on the selected storage type and platform configuration.
  • Application permissions must allow access to the mounted directory.
  • A mounted volume can hide existing files at the same path inside the image.
  • Shared writable storage requires applications that can safely handle concurrent access.
  • Removing a volume mapping does not always mean that the underlying stored data is deleted.

Common Issues and Solutions

Application cannot write to the volumeCheck directory ownership, user permissions and whether the mount is configured as read-only.
Files disappear after redeploymentConfirm that the application writes to the mounted volume path rather than the temporary container filesystem.
Application files are missing after mountingThe volume may be hiding files included in the image at the same path. Use another mount path or copy the required content to the volume.
Shared files are not visible on another nodeVerify that all nodes use the same shared storage source and correct container mount path.
Container fails to start after adding a volumeReview the source location, mount path, permissions and application startup requirements.
Volume cannot be removed safelyStop dependent writes, create a backup and confirm that the application no longer uses the mounted path.

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