1.vi /etc/docker/daemon.json
2.配置文件内容修改为：
{
"registry-mirrors": [
"https://docker.m.daocloud.io",
"https://dockerproxy.com",
"https://docker.mirrors.ustc.edu.cn",
"https://docker.nju.edu.cn"
]
}
3.执行命令
systemctl daemon-reload
systemctl restart docker