Is it possible to configure a router so it's hooked to two servers and
have it either:

1. Send requests to one server unless that one doesn't respond, and
then automatically switch over?

Is this possible for all routers currently used by the top hosting
services?

2. Send requests to two (or more) servers at once? i.e. duplicate the
requests and send to all connected servers?


I want something like this:


Router
|
------------------
| |
Server 1 Server 2