Now the idea is to add a script which would be run every time your USB device is plugged in or plugged out. You can run docker image allowing access to range of devices with specific major number, docker will add required rules for you in your host machine (this will run docker in detached mode, we will attach to it later): docker run -device-cgroup-rule='c 188:* rmw' -itd -name my_container ubuntu Run following command: $ ls -l /dev/ | grep ttyUSBĬrw-rw-rw- 1 root dialout 188, 0 Mar 1 18:23 ttyUSB0 #Example outputīased on the output you can see that the major group of tty devices is 188 in my case, so I will proceed with that. First of all, lets find cgroup properties of your USB device. Idea is to configure cgroup rules properly. Just follow the instruction line by line, all steps are explained The Safe and Proper way of accessing tty devices without -privileged mode So to add all usb webcams and serial2usb devices to your docker container, do: docker run -it -v /dev:/dev -device-cgroup-rule='c 188:* rmw' -device-cgroup-rule='c 81:* rmw' ubuntu bash
This results in something like: crw-rw-+ 1 root video 81, 0 Jul 6 10:22 /dev/video0 For example to check the device major number for a webcam connected to /dev/video0, you can do a ls -la /dev/video0. You can look it up in the linux kernel documentation. Step 1Ĭheck the device major number of the type of device you would like to add. This option does not need a -privileged container and only allows access to specific types of hardware. If you would like to dynamically access USB devices which can be plugged in while the docker container is already running, for example access a just attached usb webcam at /dev/video0, you can add a cgroup rule when starting the container. The docker run commands will work with a Linux host as well. I can only assume the same would be true for devices like /dev/ttyACM0 or /dev/ttyUSB0. Note, I had to use /dev instead of /dev/bus/usb in some cases to capture a device like /dev/sg2. In that case, you can use: docker run -it -privileged -v /dev:/dev ubuntu bash The volumes flag is only required if you want this to work with devices connected after the container is started. Note, when the command is run like this, then only previously connected USB devices will be captures. Open up a terminal with the VM and run the docker run command: host:~$ docker-machine docker run -it -privileged ubuntu bash Since the USB devices are connected to the boot2docker VM, the commands need to be run from that machine. Start the boot2docker VM: host:~$ docker-machine start default Open the VirtualBox Manager and add USB support with filters as required. To do this you can stop the VM by running: host:~$ docker-machine stop default If you are working with Windows, you'll need to add any USB rules for devices that you want Docker to access within the VirtualBox manager.
Docker for mac tty how to#
I wanted to extend the answers already given to include support for dynamically connected devices that aren't captured with /dev/bus/usb and how to get this working when using a Windows host along with the boot2docker VM. Without doing this, any newly plugged or rebooting device after the container started, will get a new bus ID and will not be allowed access in the container. Then start your container like this: docker run -v /dev/bus:/dev/bus:ro -v /dev/serial:/dev/serial:ro -i -t -entrypoint /bin/bash debian:amd64 It may be different on your system than on mine: echo 'c 189:* rwm' > /sys/fs/cgroup/devices/docker/$A*/devices.allow It's a bit hard to paste, but in a nutshell, you need to get the major number for your character device and send that to cgroup:ġ89 is the major number of /dev/ttyUSB*, which you can get with 'ls -l'.
See details here: Accessing USB Devices In Docker without using -privileged Using the cgroups approach is better in that respect and works on devices that get added after the container as started. Basically this allows the container to gain root on the host, which is usually not what you want.
You could just use -v /dev:/dev but that's unsafe as it maps all the devices from your host into the container, including raw disk devices and so forth. You have to use cgroup devices.allow get around it. device works until your USB device gets unplugged/replugged and then it stops working.
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