Hi I'm seeking some help with using Windows NLB to load balance the CAS array. After creating the NLB cluster, I need to add the hosts. However, I'm not sure which network interface adapter to use when adding the host servers. I have two NICs installed on each machine. One is dedicated for the cluster heartbeat, and the other for Public. The Public interface has DNS servers and Default Gateway configured. Please advise to which interface to use when adding the hosts to the cluster. Thanks.

Hi, You have to use the public NIC for your configurations. Regards. Shafaquat Ali.M.C.I.T.P Exchange 2007/2010, M.C.I.T.P Windows Server 2008, M.C.T.S OCS Server 2007 R2, URL: http://blog.WhatDoUC.net Phone: +923008210320

You have two NICs: one for load-balanced traffic, not a heartbeat--that's a Windows Cluster thing, which I call "NLB" one for non-load-balanced traffic, which I call "Public" Configure the NLB NIC to not register its hostname in DNS. In Advanced network configuration, be sure Public is before NLB in priority. When adding the host to the NLB cluster, specify "NLB" as the interface. Use Public's IP address for everything that is supposed to connect to the specific server, and the load-balanced IP address for stuff you want load-balanced. Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Ed, I'm getting different responses depending on the person. Most are stating to use the Public NIC (interface configured with DNS and default gateway) when adding the host to the NLB cluster. For instance I've posted the same question in the 'Deploy' forum and MS support representatives are stating to use the Public. My configuration is the following: Server1: Public Interface IP - 192.168.10.60 Subnet Mask - 255.255.255.0 DG - 192.168.10.254 DNS - 10.15.1.50 NLB Interface IP - 192.168.10.61 Subnet Mask - 255.255.255.0 DG - Not defined DNS - Not defined Server2: Public Interface IP - 192.168.10.62 Subnet Mask - 255.255.255.0 DG - 192.168.10.254 DNS - 10.15.1.50 NLB Interface IP - 192.168.10.63 Subnet Mask - 255.255.255.0 DG - Not defined DNS - Not defined NLB VIP - 192.168.10.65

The idea is to use the NLB NIC for incoming traffic, the other NIC for outgoing traffic. That's why the NLB NIC is not having having a default gateway. The MAC address of the NIC having NLB is masked by the NLB driver and relaced by a virtual MAC address, that's why, NLB nodes cannot communicate with each other using the NLB card (one MAC address). When joining clusters, you need to use the public IP so the servers can communicate with each other.

My experience is that you can't choose a NIC for outgoing traffic. Windows will use whichever of them it wants.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Actually in your case it doesn't matter since both are on the same network.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."