If there is a directory such as /var/app/data with stateful information about a container and in that same directory there is a /var/app/data/config sub-directory that needs to be shared between a container cluster, how would you create the managed volumes for data and config?
If you absolutely cannot change directory structure then try using --mount
data volume /var/app/data
config volume /var/app/data/config
The readonly option, if present, causes the bind mount to be mounted into the container as read-only.