package:docker.io:1.13.1-0ubuntu1~16.04.2
Setting up docker.io (1.13.1-0ubuntu1~16.04.2) ...
addgroup: The group `docker' already exists as a system group. Exiting.
Job for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journalctl -xe" for details.
invoke-rc.d: initscript docker, action "start" failed.
● docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Mon 2018-03-26 15:53:34 IST; 5ms ago
     Docs: https://docs.docker.com
  Process: 15211 ExecStart=/usr/bin/dockerd -H fd:// $DOCKER_OPTS (code=exited, status=1/FAILURE)
 Main PID: 15211 (code=exited, status=1/FAILURE)

Mar 26 15:53:34 lakshay-sof systemd[1]: Starting Docker Application Containe....
Mar 26 15:53:34 lakshay-sof dockerd[15211]: unable to configure the Docker d...)
Mar 26 15:53:34 lakshay-sof systemd[1]: docker.service: Main process exited,...E
Mar 26 15:53:34 lakshay-sof systemd[1]: Failed to start Docker Application C....
Mar 26 15:53:34 lakshay-sof systemd[1]: docker.service: Unit entered failed ....
Mar 26 15:53:34 lakshay-sof systemd[1]: docker.service: Failed with result '....
Hint: Some lines were ellipsized, use -l to show in full.
dpkg: error processing package docker.io (--configure):
 subprocess installed post-installation script returned error exit status 1