github.com/afein/docker@v1.8.2/contrib/init/systemd/docker.service (about)

     1  [Unit]
     2  Description=Docker Application Container Engine
     3  Documentation=https://docs.docker.com
     4  After=network.target docker.socket
     5  Requires=docker.socket
     6  
     7  [Service]
     8  Type=notify
     9  ExecStart=/usr/bin/docker daemon -H fd://
    10  MountFlags=slave
    11  LimitNOFILE=1048576
    12  LimitNPROC=1048576
    13  LimitCORE=infinity
    14  
    15  [Install]
    16  WantedBy=multi-user.target