Elastic Container Instance:Overview of data volumes

Why you need volumes

By default, container filesystems are ephemeral: data written inside a container exists only as long as the container itself. This creates two practical problems:

• Data loss on restart: When a container crashes and restarts, all files written during the previous run are gone.

• No cross-container sharing: Containers in the same elastic container instance cannot share files through the local filesystem.

Volumes solve both problems by providing storage that persists independently of the container lifecycle.

Volume types

ECI supports five volume types to cover different storage needs. Common use cases include:

• Persisting database files so data survives container restarts

• Sharing configuration files or log data across containers in the same instance

• Storing unstructured data such as images and media files in object storage

• Providing temporary scratch space for intermediate processing results

• Injecting configuration data into a container

Choose a volume type based on two key criteria: whether data must survive a restart, and whether multiple instances need simultaneous access.

OSS volumes are mounted using ossfs, which is implemented as a Filesystem in Userspace (FUSE). For write-intensive workloads, use NAS or other volumes instead.

Configure volumes

Configuring a volume is a two-step process: declare the volume at the container group level, then mount it into a specific container. The declaration uses Volume.N.Name and Volume.N.Type; the mount uses Container.VolumeMount-related parameters.