Serving images/assets from static web server
I have a web app that allows users to do many things, including uploading of images to galleries. The web server is Apache. Since apache consumes alot of memory/resources even when serving static content, I am thinking of serving the images and static content from a Nginx web server on another VPS. I don't want to use Nginx to process PHP and I don't want to use any third-party CDN for now.
Webapp : www.domain.com
Static Web Server : static.domain.com
The problem is, when a user uploads an image, how do I transfer it to the Nginx server? How do you guys do it?