Volumesfrom

Volumes-from is a Docker runtime option that allows a container to mount all volumes from another container. By mounting the source container’s volumes, the destination container can read and write to the same data store without copying data between containers. This can simplify data sharing between related services or components.

Usage is performed with the --volumes-from flag on docker run. The basic form is: docker run --volumes-from <container> [options]. By default the volumes are mounted read-write; you can add :ro to make them read-only, for example --volumes-from <container>:ro. The source container does not need to be running for the volumes to be mounted, but if it is removed the volume sharing may be lost or the container creation may fail depending on the setup.

What gets mounted is the set of volumes defined in the source container, including named volumes and, where applicable, anonymous volumes. It does not copy data; instead, the destination container accesses the same underlying storage. This makes volumes-from useful for sharing persistent data, such as database data directories or log locations, among multiple containers.

Limitations and considerations include tight coupling between containers, since the destination depends on the source container’s volumes. If the source container is removed or renamed, the volumes-from mount can break. It is also less granular than explicitly mounting individual volumes and can complicate lifecycle management. Alternatives include sharing a named volume explicitly by mounting the same volume into each container or using orchestration tooling to manage data volumes.