A sticky session keeps a client glued to a particular server. Replicating session data is expensive while J2EE server crashes are exceptional. Having said that, replicating session data to a single fail-over target nets you low-cost fault tolerance. As a special bonus prize you can purchase a load balancer with SLL acceleration.
----- Original Message ----- From: "Brian McSweeney" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, February 03, 2003 2:23 AM Subject: Re: [JBoss-user] basic clustering question > Thanks Sacha, > > > in this case, use a hardware or software loadbalancer that uses sticky > > sessions. > > what exactly are sticky sessions? And how if it's a hardware load > balancer could you do this? > > Eg, say we're running a web app. > We have two boxes A and B both running the web and ejb tiers. > Each box has a stateful session bean as a facade and also with a > stateless session bean as a facade between the web and ejb tiers. > > In front of them is a little hardware load-balancer that randomly > picks between A and B. If a client uses the stateful session bean > does it have to always have to go back to the same box? Or > can we cluster the stateful session bean too? > > thanks, > Brian > > ----- Original Message ----- > From: "Sacha Labourey" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Saturday, February 01, 2003 2:45 PM > Subject: RE: [JBoss-user] basic clustering question > > > > > this makes sense if the client is a heavyweight app (say swing). But > > > if the client is the web tier and the app is basically an internet site, > > > then > > > the ultimate client is a web browser. Now, you could have the "proxy" > > > being the code in the web tier - ie, a servlet, which could pick which > of > > > the ejb tiers to hit, as you say. > > > > in this case, use a hardware or software loadbalancer that uses sticky > > sessions. > > > > > However I would have thought it would be better to let this proxy be a > > > little hardware device that just selects which of the boxes to > > > hit, and then > > > > if it is a web app, yes. If it is a java app, no. > > > > > > > > ------------------------------------------------------- > > This SF.NET email is sponsored by: > > SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See! > > http://www.vasoftware.com > > _______________________________________________ > > JBoss-user mailing list > > [EMAIL PROTECTED] > > https://lists.sourceforge.net/lists/listinfo/jboss-user > > > > > > > ------------------------------------------------------- > This SF.NET email is sponsored by: > SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See! > http://www.vasoftware.com > _______________________________________________ > JBoss-user mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/jboss-user ------------------------------------------------------- This SF.NET email is sponsored by: SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See! http://www.vasoftware.com _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
