Well, you have to remember that you have two levels of "clustering" here. I am assuming that the F5LB is configured to connect to the two webservers and has a setting for sticky sessions and then each individual webserver is connected to the CF Cluster using the wsconfig connector. This means that F5 is managing balancing and the stickiness of requests sent to the webservers and the JRun connector is managing each webserver's connection to each CF node.
If sticky sessions is turned on in F5, then each request will always go to the same webserver, but that's all F5 controls. Once the webserver turns around and send the request to JRun, then JRun also has a "sticky or not" setting (it's sticky by default) that determines which CF server will handle the request. This means that webserver on node one may get the HTTP request but the CF engine on node two may be the one which processes the page request. This is illustrated as Figure 11 (bottom of page) on the following blog post: http://www.bpurcell.org/viewContent.cfm?ContentID=121 That blog post also has alot of other good info about clustering. If you haven't read it before, it's definitely worth a read. The other good nugget in there for you may be this code which will tell you which CF cluster node processed the request: <cfobject action="create" type="java" class="jrunx.kernel.JRun" name="jr"> <cfset servername = jr.getServerName()> <cfoutput>JRun Server Name: #servername#</cfoutput> I've done a number of cluster implementations - several at Universities. Let me know if you guys get super stuck and you are getting alot of flack about it. I might be able to help you get unstuck with a phone call or even a visit if needed. -Cameron On Dec 18, 2007 2:45 PM, Clontz Jr., Lee <[EMAIL PROTECTED]> wrote: > Thanks, everyone, for the input. > > Cameron, we've never had a clustered environment before -- we've always run > single-server. I'm not seeing the behavior you describe from the Web > servers, though. We have two Web servers behind an F5 load balancer > connecting to the two-node CF cluster, but with sticky sessions off on the CF > server the Web servers seem to hop from node to node. Is that something > configured in the JRun connector? > > Thanks, > - Lee > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Cameron > Childress > Sent: Tuesday, December 18, 2007 10:50 AM > To: [email protected] > > Subject: Re: [ACFUG Discuss] Challenges with CF7 cluster > > Lee, > > As Adam more or less mentioned, CFCs instantiated into the session > scope cannot be replicated across cluster nodes in CF7 (though it's > possible in CF8). You may want to try leaving sticky session turned > on in JRun and just count on replication for failover. It's on by > default in JRun when you setup a cluster and I suspect there may be a > reason for that. Even if you have a webserver cluster in front of the > JRun cluster and sticky session are turned off on your webserver layer > the JRun connector will continue to send requests to the same cluster > node by default except in a failover situation. > > Did you have this working on a 6.x cluster before or is this the first > time this app has ever been clustered? > > -Cameron > > On Dec 17, 2007 3:21 PM, Clontz Jr., Lee <[EMAIL PROTECTED]> wrote: > > > > > > > > > > Hey, everyone - > > > > > > > > We're implanting a CF7 cluster in a new university Web hosting environment > > and we've hit a few snags. Unfortunately, clustering seems to be one of the > > more poorly documented aspects of CF administration, so I was wondering if > > anyone had some input. > > > > > > > > We currently have two Web servers behind a load balancer, each connecting to > > a two-node CF7 cluster with J2EE session variables and session replication > > turned on. We have JRun sticky sessions turned off. > > > > > > > > In doing this, and in migrating sites to the new architecture, we've hit on > > some strange problems: > > > > > > > > > CFLOGIN session replication seems to work intermittently, particularly if > > the CFLOGIN block is within a method without Application.cfc/cfm. > > > > > > > > > We have a developer who creates an XML session object which throws a > > serialization error. > > > > > > > > > Components, in general, seem to be dodgy when hopping nodes > > > > > > > > My question, then, is twofold - 1, does Adobe assume you'll be using sticky > > sessions when clustering CF and 2, does anyone know of any good resources on > > understanding exactly what works and what doesn't in clustered environments? > > > > > > > > Thanks very much, > > > > - Lee > > > > > > > > > > ________________________________ > > This e-mail message (including any attachments) is for the sole use of > > the intended recipient(s) and may contain confidential and privileged > > information. If the reader of this message is not the intended > > recipient, you are hereby notified that any dissemination, distribution > > or copying of this message (including any attachments) is strictly > > prohibited. > > > > If you have received this message in error, please contact > > the sender by reply e-mail message and destroy all copies of the > > original message (including attachments). > > > > ------------------------------------------------------------- > > Annual Sponsor - Figleaf Software > > > > To unsubscribe from this list, manage your profile @ > > http://www.acfug.org?fa=login.edituserform > > > > For more info, see http://www.acfug.org/mailinglists > > Archive @ http://www.mail-archive.com/discussion%40acfug.org/ > > List hosted by FusionLink > > ------------------------------------------------------------- > > > > -- > Cameron Childress > Sumo Consulting Inc > http://www.sumoc.com > --- > cell: 678.637.5072 > aim: cameroncf > email: [EMAIL PROTECTED] > > > ------------------------------------------------------------- > Annual Sponsor FigLeaf Software - http://www.figleaf.com > > To unsubscribe from this list, manage your profile @ > http://www.acfug.org?fa=gin.edituserform > > For more info, see http://www.acfug.org/mailinglists > Archive @ http://www.mail-archive.com/discussion%40acfug.org/ > List hosted by http://www.fusionlink.com > ------------------------------------------------------------- > > > > > This e-mail message (including any attachments) is for the sole use of > the intended recipient(s) and may contain confidential and privileged > information. If the reader of this message is not the intended > recipient, you are hereby notified that any dissemination, distribution > or copying of this message (including any attachments) is strictly > prohibited. > > If you have received this message in error, please contact > the sender by reply e-mail message and destroy all copies of the > original message (including attachments). > > > ------------------------------------------------------------- > Annual Sponsor FigLeaf Software - http://www.figleaf.com > > To unsubscribe from this list, manage your profile @ > http://www.acfug.org?falogin.edituserform > > For more info, see http://www.acfug.org/mailinglists > Archive @ http://www.mail-archive.com/discussion%40acfug.org/ > List hosted by http://www.fusionlink.com > ------------------------------------------------------------- > > > > -- Cameron Childress Sumo Consulting Inc http://www.sumoc.com --- cell: 678.637.5072 aim: cameroncf email: [EMAIL PROTECTED] ------------------------------------------------------------- Annual Sponsor FigLeaf Software - http://www.figleaf.com To unsubscribe from this list, manage your profile @ http://www.acfug.org?fa=login.edituserform For more info, see http://www.acfug.org/mailinglists Archive @ http://www.mail-archive.com/discussion%40acfug.org/ List hosted by http://www.fusionlink.com -------------------------------------------------------------
