I am doing a project that has to incorporate load-balancing using OpenStack platform. It boils down to spreading browser requests, that execute calculation-heavy scripts, across several virtual machines running some distro of Linux.
Due to all installation attempts of OpenStack going horribly wrong, I ended up using TryStack.org, which is a free and working environment. The obvious problem here is, it offers very limited resources. For instance, I can have only 1 floating (external) IP, which can be assigned to only 1 single instance (virtual machine) and there are measures that make it impossible to change it via API.
Due to those limitations, I have to work with a very peculiar setup: I have a network with nodes A, B and C. A, B and C can communicate with each other, but only A has an external IP, ie. is accessible by browser.
Therefore, I have to:
direct all browser requests to A,
have A request (and wait for) execution of calculation-heavy scripts on B/C,
make B/C send back results once they are finished
and finally have A dress results in HTML and send response back to the browser.
Is there any mechanism in PHP that can do 2. and 3.? If not, what (Linux-compatible) language/technology can do that? (I have already written almost all of the code in PHP, but I suppose I can switch.)
Alternatively: is there some other free OpenStack service that would allow me to give every instance an IP (in which case the spreading problem could be solved via simple redirects)?
As arkascha advised in the comments, I used curl to simply send a page request from A to B/C, and then parsed the page using text manipulation.
