问题：
[yuyongxr@localhost ~]$sudo docker run -d --name nginx -p : nginx
WARNING: IPv4 forwarding is disabled. Networking will not work.
解决方法：
[yuyongxr@localhost ~]$ sudo vim /usr/lib/sysctl.d/00-system.conf
#添加如下代码：
net.ipv4.ip_forward=
重启network和docker服务
[yuyongxr@localhost ~]$ sudo systemctl restart network
[yuyongxr@localhost ~]$ sudo systemctl restart docker