Is there any way to configure nginx (or other quick reverse proxy) dynamically?

Question

Suppose we have several identical nodes which are the application servers of some n-tier service. And suppose we use Apache ZooKeeper to keep all the config\'s of our distribute

Answer 1

It is possible using HAProxy and its UNIX domain socket interface: http://cbonte.github.io/haproxy-dconv/configuration-1.5.html#9.2.

It supports switching a server or an entire front-end from down to up and back again on the fly. With a configuration file that defines two sets of front-ends, each configured for one specific state, you would be able to achieve what you want.