Ubuntu 19.04 安装docker

配置国内源：
deb https://mirrors.ustc.edu.cn/ubuntu/ disco main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ disco-updates main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ disco-backports main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ disco-security main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ disco-proposed main restricted universe multiverse
deb [arch=amd64] http://mirrors.ustc.edu.cn/docker-ce/linux/ubuntu disco stable

sudo apt-get update
sudo apt-get install \
    apt-transport-https \
    ca-certificates \
    curl \
    software-properties-common

curl -fsSL http://mirrors.ustc.edu.cn/docker-ce/linux/ubuntu/gpg | sudo apt-key add -
sudo apt-get update
sudo apt-get install docker-ce