I have a website that we load-balance across a few machines. The load-balancer (a Brocade ServerIron ADX) is on the local network. I know it has the capability to configure a "backup" ip address to use as the "real", but it would need to be on a local network. How can I provide a "fail whale" to my users and a status update message when my entire environment may be offline due to a FW, LB, or multiple-server failure? Since DNS doesn't have the ability to provide a weighted A-Record backup (like SRV records), what are my options?
Ideally, the solution should be able to step in automatically as soon as my site becomes unreachable and inform my users that our response teams on working on the problem.