Volumes in Sandbox Forks and Snapshots

AgentENV automatically carries mounted volumes through sandbox fork and snapshot operations. You do not need to fork or snapshot each mounted volume separately.

Fork a Sandbox

When a sandbox is forked, AgentENV processes every mounted volume for every child sandbox:

• Each mounted exclusive volume gets an independent copy-on-write volume fork. The child mounts the new volume at the same guest path and can modify it without changing the source sandbox’s volume.
• Each mounted ro volume remains mounted from the same read-only volume. It is safe to share because neither the source nor a child can modify it.

This behavior is separate from manually creating a reusable volume fork with aenv volume create --from-volume.

Snapshot a Sandbox

When a sandbox is snapshotted, every mounted volume is included automatically. The volume snapshot records its layers, size, mount path, and access mode. Starting a sandbox from that snapshot creates new volumes with the captured contents and mounts them at the same paths. An exclusive volume remains exclusive; a read-only volume remains read-only.

Volume snapshots are independent from their source volumes. Deleting a source volume does not remove volume data already committed into a sandbox snapshot.