You are correct that the JRun clustering is not application aware. As a technicality, I wouldn't blame ColdFusion. I'm pretty certain CF is just making use of the J2EE clustering abilities. Read: Every other J2EE app written in Java would have the same problems. (I think)
The JRun connectors will NOT send traffic to an instance if it is turned off, stopped, or otherwise not accessible. It WILL however try to send requests to that instance even if it is: * Busy * Low on memory * Has a full queue * At 100% CPU utilization * Has some other sort of higher level application error All you get is basic round robin. You can assign priority to beefier servers, but the same rules above still apply. If you want to actually manage your traffic based on the state of the application running on each instance, you have to get a Hardware load balancer capable of hitting a "heartbeat" page which outputs some metrics about that instance and how busy it is. I know, I was disappointed too when I first messed with clustering in Enterprise, but that's the way it is. If your budget doesn't allow for anything more fancy smancy-- your best bet is just to monitor the instances well and restart one if it hangs and use a program like SeeFusion to auto-kill any long running stuff that might be taking down that instance. Ultimate high-availability clustering with thorough redundancy at every level= $,$$$,$$$ The rest of us just get as close as we can. ~Brad -----Original Message----- From: Rick Root [mailto:[EMAIL PROTECTED] Sent: Monday, May 12, 2008 7:22 AM To: CF-Talk Subject: load balancing / failover I've determined that Coldfusion clusters suck. They're just DUMB. If one instance in a cluster freezes, other people still get referenced to that instance and get no response. CF clustering provides no real "failover" from one instance to another, so it seems. Am I wrong on this? I don't have a setup that warrants having multiple physical servers and a hardware load balancer so I'm wondering if there are any decent software load balancing solutions that will provide more reliability than CF clustering does. Basically I'd like to have two IIS servers each using a separate CF instance, and have a software load balancer distribute the requests to each (maintaining sticky sessions), and if one instance stops responding (due to failure or high load), force requests onto the available instance. Suggestions? -- Rick Root New Brian Vander Ark Album, songs in the music player and cool behind the scenes video at www.myspace.com/brianvanderark ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Adobe® ColdFusion® 8 software 8 is the most important and dramatic release to date Get the Free Trial http://ad.doubleclick.net/clk;192386516;25150098;k Archive: http://www.houseoffusion.com/groups/CF-Talk/message.cfm/messageid:305097 Subscription: http://www.houseoffusion.com/groups/CF-Talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
