I've got two Dell PowerEdge 2950 servers. In order to (hopefully) eliminate any downtime, I must implement a solution to detect and adjust to component failures, environment failures, etc ... the usual "downtime is the enemy" scenario.
From this point on, I'll refer to the servers as server(s), since the solution implemented may combine the two servers into one logical server, (honestly, one logical server would be preferred).
I'll have ~15 thin clients all pointing to the server(s) mentioned above. The server(s) will act as a Terminal Server. The clients will connect to the server(s) and run an instance of a client GUI. The actual server(s) itself will run the server-version of the same application, serving the client GUI's with the information/data they require ... (I hope that made sense!)
I've been recommended to use Marathon Technologies everRun 2G software. While this seems like a fair solution, it's also $12,000 ... seems a bit pricey to me, (that may be me showing my lack of experience in this field however) ...
Is there a more cost-efficient solution to such a scenario? I've been checking into a solution involving Citrix XenServer at the moment, but have yet to make much leadway with it ...
How can one implement fault tolerance to the degree mentioned above?
EDIT: The servers are running Windows Server 2003 Enterprise.
EDIT: To clarify my miscommunication, I'm shooting for failover to the still-running node in the event of a disaster. The application to be hosted provides the control of a large number of electronically-locked doors and intercoms. Therefore, if the application is unavailable, no doors will open and no communication via intercom can occur. Yikes!
EDIT: Well, after some scope change, funding and other non-technical project adjustments, the solution I'm moving forward actually used none of the approaches listed :) Long story short, we're maintaining two separate Terminal Servers; a primary and a hot backup. The switch between the two in an emergency scenario will be manual, (although it'll actually be just as fast if not faster then we originally anticipated). The server hardware (two NIC's, two battery supplies and two UPS's) will address the failover functionality required. Thanks for all your feedback, greatly appreciated!