External load balancing for the cluster cannot be enabled because the external network adapter of the Remote Access server ...

External load balancing for the cluster cannot be enabled because the external network adapter of the Remote Access server is configured with IPv6 addresses only. If cluster servers have a single adapter, configure the adapter with IPv4 addresses and one IPv6 address only. If cluster servers have two adapters, configure the external adapter with IPv4 addresses, and the internal adapter with at least one IPv6 address.