I'm sorry if my title seems vague and uninformed, because that's the extent of my understanding right now.
I'm thinking of hosting a web server (with form methods, inputs, etc.) using an Arudino and an Ethernet shield. Now from what I've read, I know the web page (HTM/HTML file) does not have to be hardcoded into the microcontroller, but can instead by stored locally from an SD card that is read by the arduino. I know that level of separation is possible. However, I'm going to be away from my server quite a bit, and I'd like to be able to work on the web files regularly without having to physically restart the Arduino, remove the SD card and update the files, etc. I was wondering, since there can be already a level of separation between the HTML file and the Arduino, is it possible to 1)store the file online, in a file hosting service (maybe dropbox or skydrive or the like) so that the file could be read, 2)have the arduino read the file and host it as a webpage?
To rephrase, I'm trying to have two copies of the web page html; one stored on the SD card in the arduino, and one I'll work on while away from the arduino. What I'm trying to do is send this updated web page source file to the arduino and have it overwrite and host the new,updated web site file. I hope I'm being clear. If there's some easier option that I'm missing, that'd be helpful too!
You should be able to use the Ethernet shield for GET requests too, so possibly you could poll your web server every so often (use a HEAD method & check for a 304 Not modified response, if not, grab the new page) and store it to your SD card.
In this way, the SD card could act as a cache for the Arduino, but it would still be able to grab new content when available from your remote server.