Hey all... up front, i'm not a server guy. just a code monkey :)
with that disclaimer out of the way... got a question about load balancing and failover of cf servers. as i understand it... there is the concept of "sticky sessions", where all requests by a particular user "stick" to a particular machine in the cluster. in theory, this balances the load over the servers. but if one server were to go down, all users on that server would subsequently go down with the ship (so to speak). so you have load balancing, but not failover. in a situation where you don't implement sticky sessions, various requests from a given user would be bounced around from machine to machine. this way the load balancing remains intact, and if a single machine in the cluster fails... nobody knows (they're just not bounced to that particular machine). the problem in this situation is... session variables. a user gets bounced from machine to machine, but their session does not. it's this session variable issue that i'm trying to explore/solve. at a previous job, we used a product called "Coherence" from tangosol (now owned by Oracle) (see http://www.tangosol.com/coherence-overview.jsp). the coherence box acts as a dedicated session variable repository in the cluster... so requests can be bounced from server to server and still have access to session variables. seems to be a viable product... but i'm trying to do the necessary due diligence in exploring all of the options. we haven't moved to CF8 yet (still on CF7), but I had heard that CF8 would actually have this functionality built in (the ability to use sessions in a clustered environment). quick googling tho seemed to indicate that this was an "expensive" process and not necessarily recommended (?) can anyone shed any light on how to handle this situation? i know we can move to client vars and use a db for client variable storage... but i'd prefer to stick with session variables if at all possible. thanks! -- Charlie Griefer ================================================ "...All the world shall be your enemy, Prince with a Thousand Enemies, and whenever they catch you, they will kill you. But first they must catch you, digger, listener, runner, prince with a swift warning. Be cunning and full of tricks and your people shall never be destroyed." ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Get involved in the latest ColdFusion discussions, product development sharing, and articles on the Adobe Labs wiki. http://labs/adobe.com/wiki/index.php/ColdFusion_8 Archive: http://www.houseoffusion.com/groups/CF-Talk/message.cfm/messageid:291857 Subscription: http://www.houseoffusion.com/groups/CF-Talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
