修改vim /lib/systemd/system/docker.service这个文件
ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:2375 -H unix:///var/run/docker.sock
重启docker
systemctl daemon-reload
systemctl restart docker
开启端口
firewall-cmd --zone=public --add-port=2375/udp --permanen
重启防火墙
systemctl restart firewalld.service