Remove deprecated '-d' option to start daemon
@@ -132,7 +132,7 @@ You can configure the Docker daemon with the `--registry-mirror` startup
parameter:
```bash
-$ docker --registry-mirror=https://registry.docker-cn.com -d
+$ dockerd --registry-mirror=https://registry.docker-cn.com
```
Or you can add "https://registry.docker-cn.com" to the `registry-mirrors`
