We use two layers. We have a software based load balancer that uses Virtual IPs to handle requests. This is soon to be exchanged for a hardware based Cisco solution, but still using Virtual IPs. The software solution is supposed to send requests to the most available server, but it never seems to get a good equality rate.
Our second layer is the JRun clusters themselves. You get several different algorithms, and off the top of my head they are. * round-robin - default. Load is spread equally amongst machines. If session stickiness is enabled (and the JSessionIDs are correct), this is negated and you are pushed to the same machine every time. If that machine fails, round-robin will take affect again until the machine is back online. When this happens you will again "stick" to that one machine again. If replication is in place, this should be transparent to users. * weighted round-robin. Load is distributed to the machine designated by you to have the highest priority. This is usefull if the machines are different enough to warrent sending traffic to the strongest servers. * random round-robin. Requests are randomly distrubuted around the cluster. We use the default round robin with session stickiness enabled. You cannot turn this off, by the way. There is no option to only send to one given server (well, except that's what session stickiness is for, right?). But then again, that would defeat the purpose of failover, I suppose. It just makes it difficult to troubleshoot errors at times. Which is why we purchosed FusionReactor for all of our servers ;). It also means you'll want to use the default Jrun web server to do administration, instead going through the CFIDE mapping of the cluster (oh how I wait for this to get into a future build of CF). Matthew Williams Geodesic GraFX www.geodesicgrafx.com/blog Quoting Brad Wood : > Thank you VERY much for the information. This is exactly the kind of > wisdom I was hoping to extract. > > Matthew, tell me-- what type of load balancing do you use for your > clusters? > > ~Brad > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Upgrade to Adobe ColdFusion MX7 Experience Flex 2 & MX7 integration & create powerful cross-platform RIAs http://www.adobe.com/products/coldfusion/flex2/ Archive: http://www.houseoffusion.com/groups/CF-Talk/message.cfm/messageid:271911 Subscription: http://www.houseoffusion.com/groups/CF-Talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
