Proxmox multi-node cluster with single IP (IPv4)

[Pumpapa]

(How) is it possible to have a two-node cluster with only a single external IP (IPv4)?
I would like to get a second node as a failover for the first, but I have only the single IPv4.

Each node could connect externally with an IPv6. Is IPv6 in Proxmox stable enough to set up failover this way?
Could the two nodes connect directly through their second NIC in a private (IPv4 network), for instance using a Xover cable?

Is all this making any sense?

 

[Dragoon]

You would have to set them on a private ip and have a router do your load balancing.