I want to implement BM clustering with load balancing according to AppNote written by Steve Aitken from March 25, 2005.

It's clear that I need to use two private addresses (from the example, these are and However, I'm not sure what are IP addresses and used for?

Existing BM servers have two NICs: first defined as private and the second as public addresses connected directly to Internet (they are from different subnets).