Description of problem: When using terraform to bring up a new EC2 instance with Docker, I wanted to modify the dm.basesize option before starting Docker. To do this, my script adds a line to the /etc/sysconfig/docker-storage file: DOCKER_STORAGE_OPTIONS= --storage-opt dm.basesize=50G However, when it then tries to start Docker with systemctl start docker.service I was getting an error: Error starting daemon: error initializing graphdriver: Unknown option dm.basesize I had used this same line before, but realized that it was after Docker had been started at least once on the server. So then I changed things to: systemctl start docker.service Add the line to /etc/sysconfigdocker-storage systemctl restart docker.service This works fine. Maybe Docker needs to be started at least once on the server in order to initialize the storage subsystem somehow? Before that's done, it doesn't recognize the storage option. This is sort of crazy, so is there a proper fix/workaround? Version-Release number of selected component (if applicable): Output of "docker version": Docker version 1.7.1, build 446ad9b/1.7.1 This is on AWS EC2, running CentOS Linux release 7.1.1503 (Core). I first asked this as an issue against Docker (https://github.com/docker/docker/issues/21037) but they said since it's a Red Hat-supported build of Docker it should be asked here.
changing component to 'docker'. 'docker-io' isn't used anymore.
Stephen can you check if this is actually a bug. I don't think it is.
Right, I agree with Dan, I think it was a misunderstanding of the options available for the config file. The option in the config file should be EXTRA_DOCKER_STORAGE_OPTIONS. I think the user wanted to directly append the dm.basesize command to the DOCKER_STORAGE_OPTIONS seen in the default /usr/lib/docker-storage-setup/docker-storage-setup config file.