Currently I try to simulate my app as distributed servers, so I let them run on localhost:9000 and localhost:9001, i tried using apache load balancer but it is really hard to config on mac, my idea is the second server localhost:9001 will be kept ideal and the requests only be redirected to them when the first server is downed. Is there any good free program can do that ? (except Apache httpd).
Extra functions: my application is written in java and maintain an in-memory object, is there any service that can synchronize that object between 2 servers so they can keep uptodate status of other (the second one takes state of the first one)? Is there any app can support that?

Thank you very much.