net-proxy
HA-Proxy is a TCP/HTTP reverse proxy which is particularly suited for high availability environments.
It can:
- route HTTP requests depending on statically assigned cookies
- spread the load among several servers while assuring server persistence through the use of HTTP cookies
- switch to backup servers in the event a main one fails
- accept connections to special ports dedicated to service monitoring
- stop accepting connections without breaking existing ones
- add/modify/delete HTTP headers both ways
- block requests matching a particular pattern
Its event-driven architecture allows it to easily handle thousands of simultaneous connections on hundreds of instances without risking the system's stability.