Chris, I've sent you a custom tag I wrote off list that should stop race conditions across servers, as for maintaining state, if you aren't going to use client vars in a cluster, then you need to use sticky sessions so that each users lands and remains on that server for the length of their session. This is usually achieved with round robin DNS and/or specialist load balancing software.
The only clusters I ever built all used a dedicated SQL Server DB (cookiejar) to store the client vars in and another SQL Server machine for the application DB because the amount of hits to cookiejar was 2 or 3 per page request depending on what was happening as I recall so splitting out the resources made sense when we got to very high loads. Paul > Sean (or anyone else!), > > In a post "Which Framework do you use", You said "Mostly the frameworks > are all designed to manages requests and data on a single server. I > never use client variables (and I've only ever worked on clustered CFMX > Enterprise systems)." May I ask how you maintain session state? I need > to take into account users behind multiple proxies (AOL), and from what > I have read you can either include link tokens in every single link / > form post on your site, you can save data to a cookie (which is not > 100% > reliable or secure), or you can use a combination of a url token and > client variables stored in a shared database file between all the > servers. What works best for you? Are you using the built in cluster > capability in Coldfusion, or a hardware device? > > Also, I have been trying to find out how effective cflock is in a > clustered environment. Looking at the cflock tag, the name of the lock > and the scope are mutually exclusive. I was rather hoping I could name > a > lock in the client scope (which would be shared between the servers, so > the others would wait for the lock to release). How do you ensure that > 2 different servers don't overwrite the same data, or get into race > conditions on the database? > > Thanks in advance! > > Chris ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Deploy Web Applications Quickly across the enterprise with ColdFusion MX7 & Flex 2 Free Trial http://www.adobe.com/products/coldfusion/flex2/?sdid=RVJU Archive: http://www.houseoffusion.com/groups/CF-Talk/message.cfm/messageid:276890 Subscription: http://www.houseoffusion.com/groups/CF-Talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
