Docker on Cumulus Linux

Cumulus Linux can be used to run the Docker container platform. You can install Docker Engine directly on a Cumulus Linux switch and run Docker containers natively on the switch.

To set up Docker on Cumulus Linux, run the following commands as root.

1. Install the authentication key for Docker:

   root@switch:~# curl -fsSL https://download.docker.com/linux/debian/gpg | apt-key add -
   

2. Configure the repositories for Docker:

   root@switch:~# echo "deb [arch=amd64] https://download.docker.com/linux/debian buster stable" >/etc/apt/sources.list.d/docker.list
   

3. Install the Docker package:

   root@switch:~# apt update
   root@switch:~# apt install -y docker-ce
   

4. Configure Docker to minimize impact on the system’s firewall and forwarding configuration:

   root@switch:~# cat >/etc/docker/daemon.json <<EOD
   {
      "iptables": false,
      "ip-forward": false,
      "ip-masq": false
   }
   EOD
   

5. Configure Docker to run in the management VRF:

   root@switch:~# cp /lib/systemd/system/docker.service /lib/systemd/system/docker@.service
   root@switch:~# sed -i -re '
         /^Requires=docker.socket$/ d;
         /^ExecStart\>/ s/-H fd:\/\/ //
      ' /lib/systemd/system/docker@.service
   
   root@switch:~# echo "docker" >>/etc/vrf/systemd.conf
   
   root@switch:~# systemctl daemon-reload
   root@switch:~# systemctl mask docker.socket
   root@switch:~# systemctl disable --now docker.service
   root@switch:~# systemctl enable --now docker@mgmt
   

6. Test your installation by running the hello-world container:

   root@switch:~# docker run hello-world