cgroupfs-mount | especially structured for Debian packaging | Continuous Deployment library

The post installation script of Docker includes its service to start. Docker service initialization consist of its bridge to be set up. I think the Docker bridge couldn't run in your situation.

Possible solutions:

• If you use any VPN or anything else that may conflict in IP configurations with Docker, turn it off and try sudo apt install -f to fix broken installations.
• Try restarting Network Manager service using sudo service network-manager restart and then sudo apt install -f.

Issuing the following commands should fix enough corrupted files to allow you to reinstall Perl using apt:

Lubuntu 16.04 comes with systemd by default. At some point you must have started up a jenkins instance in docker - it's hard to tell exactly what started the process initially. However, systemd would be what is currently causing it to start. In order to stop it from running, run the following commands:

systemctl status docker <- Find out of systemctl thinks docker is running.

It'll likely show something like this:

● docker.service - Docker Application Container Engine Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor preset: disabled) Active: active (running) since Sun 2017-05-21 22:59:46 EDT; 1 day 17h ago Docs: http://docs.docker.com Main PID: 1314 (dockerd-current) Tasks: 14 (limit: 8192) CGroup: /system.slice/docker.service └─1314 /usr/bin/dockerd-current --add-runtime oci=/usr/libexec/docker/docker-runc-current --default-runtime=oci --containerd /run/containerd.sock --exec-opt native.cgroupdriver=systemd --userland-proxy-path=/usr/libexec/docker/docker-proxy-current --selinux-enabled --log-driver=journald

To stop it, run systemctl stop docker and then systemctl disable docker. As a last resort if this doesn't work, you can run systemctl mask docker.