How can I configure balancing on nginx?

Question

Nginx

The question is.
there is a wish to hang up on nginx such tasks:
a) to give the cached statics.
b) skip for itself and balance the load on the rest server cluster.
it's kind of like doing it.
The question is - is it possible to somehow intelligently set up balancing and is it possible that nginx has it?
something like depending on the request / url or something else? (I just read about balancing by the apishnik hash) I
just want to attach a separate piece of data to each node for speed, and so that the balancer balances properly, it would be very cool if after the master fell off, he could send the user to the slave.
And more interestingly, is it possible to change these settings on the fly without restarting nginx?
It should be noted that these are Napoleonic plans, which are still far from the fact that they are destined to come true, but it’s nice to do such a thing for yourself, and in terms of development, boost + 100%)

Answer 1

nginx.org/en/docs/http/load_balancing.html
If depending on the url, then each location has its own upstream.