kubespray/roles/docker/templates/docker.service.j2

[Unit]
Description=Docker Application Container Engine
Documentation=http://docs.docker.com
{% if ansible_os_family == "RedHat" %}
After=network.target docker-storage-setup.service
Wants=docker-storage-setup.service
{% elif ansible_os_family == "Debian" %}
After=network.target docker.socket
Wants=docker.socket
{% endif %}

[Service]
Type=notify
{% if docker_storage_options is defined %}
Environment="DOCKER_STORAGE_OPTIONS={{ docker_storage_options }}"
{% endif %}
Environment=GOTRACEBACK=crash
ExecReload=/bin/kill -s HUP $MAINPID
Delegate=yes
KillMode=process
ExecStart={{ docker_bin_dir }}/docker{% if installed_docker_version.stdout|version_compare('17.03', '<') %} daemon{% else %}d{% endif %} \
          $DOCKER_OPTS \
          $DOCKER_STORAGE_OPTIONS \
          $DOCKER_NETWORK_OPTIONS \
          $DOCKER_DNS_OPTIONS \
          $INSECURE_REGISTRY
{% if not is_atomic and systemd_version.stdout|int >= 226 %}
TasksMax=infinity
{% endif %}
LimitNOFILE=1048576
LimitNPROC=1048576
LimitCORE=infinity
TimeoutStartSec=1min
# restart the docker process if it exits prematurely
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s

[Install]
WantedBy=multi-user.target