Microsoft Network Load Balancing has one or two “interesting” issues due to the way it does networking. More specifically, it utilises a Multicast MAC address with a Unicast IP address. Someone much smarter than me explains the ins and outs of the issue here.
This issue manifests itself in that clients outside of the cluster’s LAN cannot connect to the IP.
Now that we understand the issue, how do we resolve it? The fixes listed in the article are all valid, however we can get this working by tweaking the config on our Nexus.
no ip redirects
ip address 192.168.10.1/24
ip arp 192.168.10.100 03BF.0A03.00CF
description Server Farm
Your clients should now be able connect to the cluster IP address without issue.