The problem is that load balancers are only as smart as their implementation. We have been running for years with our load balancer checking a static html file on the tomcat server….while this provides a check of ‘is the tomcat server working’, it does not provide a check of ‘is the mid-tier application functioning’….so I respectfully disagree that the lb or the lb team know how to configure it properly. We are using Cisco’s CSM (Content Switching Module), and I don’t want to just rely on a port probe because I don’t trust that it means I’m functional.
From: Action Request System discussion list(ARSList) [mailto:[email protected]] On Behalf Of Michael Latham Sent: Friday, December 10, 2010 9:29 AM To: [email protected] Subject: Re: Load Balancers and how? ** The LB itself should be able to determine that if it is configured correctly. In particular on Apache you would use mod_proxy and mod_proxy_balancer modules simultaneously with some ProxyPass directives defined. Any of your web server admins should have a very good idea of what I am talking about. If I were not typing this from my obnoxious touchscreen I would go into more detail. In any case if you need more precise help reply stating so and I will be happy to help on e I get to my desk. Cheerios! Sent from my Windows Phone _____ From: LJ LongWing Sent: Friday, December 10, 2010 10:49 AM To: [email protected] Subject: Load Balancers and how? > Ok..I'm going down a road that I KNOW some of you have travelled before, I > need your travel tips. We are setting up a server group on 7.5 Windows and > we are putting a load balancer in front of it. How do you all tell if a > node is up? There are 4 types of probes that I'm being told are available. > > > > PING > > HTTP > > TCP > > Script > > > > Ping - Obviously doesn't tell you anything other than the host OS is up > > HTTP - Won't work for telling if a remedy service is up > > TCP - My instincts are telling me that this one simply does something > similar to a telnet to a given port, if the port allows you 'in', then the > service is considered up. I don't consider this one viable because it > doesn't 'test' much and I expect that my remedy server could respond to the > port request without actually being functional > > Script - This one is the most promising in my mind, but I know nothing about > the scripting language of TCL. > > > > How does the rest of the remedy world 'verify' that their remedy instance is > online so that their load balancer can know to route traffic to it or not. > I just this week finished a java servlet that allows the mid tier load > balancer to know if an individual node is working properly, but the same > can't be said yet for Remedy..any and all help is appreciated > > > _______________________________________________________________________________ > UNSUBSCRIBE or access ARSlist Archives at www.arslist.org > attend wwrug11 www.wwrug.com ARSList: "Where the Answers Are" _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _______________________________________________________________________________ UNSUBSCRIBE or access ARSlist Archives at www.arslist.org attend wwrug11 www.wwrug.com ARSList: "Where the Answers Are"
