在一次安装rtmp推流服务时，总是无法下载源，估计是国外资源下载超时照成的，于是想到修改为国内源。
docker pull alfg/nginx-rtmp
Using default tag: latest
latest: Pulling from alfg/nginx-rtmp
530afca65e2e: Retrying in 7 seconds
c20ba4fc8a2c: Retrying in 1 second
7d60e766d5fd: Retrying in 10 seconds
13fcd85631ea: Waiting
58b7d31a1710: Waiting
f1d974888e5e: Waiting
3cf0b843d524: Waiting
c99ac4327a57: Waiting
6a0e61809b5b: Waiting
error pulling image configuration: download failed after attempts=6: EOF设置方法也很简单：
找到并打开：windows-daemon-options.json,修改"registry-mirrors"
"registry-mirrors": ["registry|redacted","https://2rz9eh73.mirror.aliyuncs.com"],