So, despite Docker 1.3 now allowing easy access to external storage on OSX through boot2docker for files in /Users/, I still need to access files not in /Users/. I have a settings file in /etc/settings/ that I'd like my container to have access to. Also, the CMD in my container writes logs to /var/log in the container, which I'd rather have it write to /var/log on the host. I've been playing around with VOLUME and passing stuff in with -v at run, but I'm not getting anywhere. Googling hasn't been much help. Can someone who has this working provide help?
As boot2docker now includes VirtualBox Guest Additions, you can now share folders on the host computer (OSX) with guest operating systems (boot2docker-vm). /Users/ is automatically mounted but you can mount/share custom folders. In your host console (OSX) :
$ vboxmanage sharedfolder add "boot2docker-vm" --name settings-share --hostpath /etc/settings --automount
Start boot2docker and ssh into it ($boot2docker up / $boot2docker ssh).
Choose where you want to mount the "settings-share" (/etc/settings) in the boot2docker VM :
$ sudo mkdir /settings-share-on-guest
$ sudo mount -t vboxsf settings-share /settings-share-on-guest
According that /settings is the volume declared in the docker container add -v /settings-share-on-guest:/settings to the docker run command to mount the host directory settings-share-on-guest as a data volume.
Works on Windows, not tested on OSX but should work.