When an SSL offload on a load balancer is required, its important to keep in mind that an additional IP is required. For example, if 4 load balanced IP addresses are needed, the server would need to have 5 in total.

This requirement is due to the HTTP redirect running in IIS and as such, must be bound to its own IP since everything is on one port (port 80)

When there is no SSL offload all the instances can run on port 443 and then IP addresses can be shared for the redirect bound to port 80.