I have two Windows 2016 VMs set up as an NLB cluster. Each guest has two interfaces, one of which is for the NLB, the other for other traffic.
I've added an IPv4 and an IPv6 address to the cluster. Both are set up to use IGMP multicast, with no affinity. Each has a separate mac address, and I've added these MACs to our core switch, as we use several hosts with VMotion.
IPv4 works fine from anywhere, but I am unable to access the IPv6 address. If I go into the cluster properties and change the cluster ip address under the cluster parameters tab to the IPv6 address, IPv4 stops working.
This leads me to suspect that dual-stack configuration of NLB is not supported, but requires a separate network adapter for each of IPv4 and IPv6.
What makes this all somewhat headscratching, is that ping6 works from one linux server on the same vlan, getting duplicate replies, as both guests reply. But from the router or a server on another vlan, ping of the ipv6 address fails.
Any insights on this would be greatly appreciated.