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I have Two webseervers(WS1, WS2). I have added NLB component on both the machines. In WS1, i have added a cluster with IP as (eg:xx.yy.zz.100) and added WS1, WS2 to the same cluster. Now i have deployed application in WS1& WS2 and tried accessing the cluster IP address from WS1 and WS2. App opened. Now i have test machine which is in the same domain of WS1 and WS2. I tried accessing the application with clustered IP in the test machine, it did not work.However it is working when accessed with the dedicated IP of WS1 and WS2. But for making NLB i have to access the app with clusted IP. Help asap would be appriciated.

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I'm not familiar with NLB except to fear it as a potential fountain of network problems. However, from a troubleshooting perspective, have you verified that the clustered address has arp'd correctly? Try pinging the cluster IP address from another machine (not in the cluster) and then checking the arp table on that machine. If the entry for that IP address shows as "Incomplete", then it's not arp'ing correctly.

Hope that helps...

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Thanks for the answer; its the problem with network. IP is not registered in ARP table. Thanks once again – krish Dec 18 '09 at 7:17
well, it's only a "network" problem if your server is sending out the arp and the network isn't propagating it. Does NLB do a gratuitous arp? – Greeblesnort Dec 19 '09 at 2:47
+1 to fear it. I've had microsoft engineers tell me point blank to run away from it, as it's not been touched in years by MS. You'll do yourself a big favor by getting a dedicated Loadbalancing appliance, or taking some time to research OSS options such as HAPROXY, etc. – Tatas Jun 17 '11 at 19:11
thanks for the +...I've been told similar by both networking and MS techs. I've never actually bothered to dig into the guts of NLB to understand the actual workings of it, but it's my understanding that it essentially replicates (i.e., converts to broadcast) traffic between the nodes? – Greeblesnort Aug 3 '11 at 18:18

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