Enable writeable shared folders on VirtualBox


I’m trying to set up a VirtualBox machine that runs RancherOS to start a container that then the host can access through a) port 8888 and b) through a shared folder. The app in the container will be editing files created by the host and the edits should be persistent.

I have the working version at:


And a description of the process I’m following here.

I have figured out a), but cannot crack b). I’m currently linking the editable folder in the container to the /media folder, but any attempt to write at that results in “permission denied”.

Further, I can’t figure out how to link the /media fodler (or if it’s easier, whichever is -v mounted in the container) to the host through VirtualBox.

I’ve searched quite a bit on forums and documentation but I can’t seem to find a solution.

Any idea, pointer or suggestion would most welcome. Thank you very much in advance!