What Pound is:
- a reverse-proxy: it passes requests from client browsers to one or more back-end servers.
- a load balancer: it will distribute the requests from the client browsers among several back-end servers, while keeping session information.
- an SSL wrapper: Pound will decrypt HTTPS requests from client browsers and pass them as plain HTTP to the back-end browsers.
- an HTTP/HTTPS sanitizer: Pound will verify requests for correctness and accept only well-formed ones.
- an HTTP/1.1 proxy: Pound will accept requests from HTTP/1.1 clients on one connection even if the back-end server is HTTP/1.0. Connections to the server will be reopened as necessary.
- a failover-server: should a back-end server fail, Pound will take note of the fact and stop passing requests to it until it recovers.
- a request redirector: requests may be distributed among servers according to the requested URL and the presence or absence of headers, based on pattern matching.
むしろ apache 2.0 に load balancer なモジュールとかはないのだろうか?