Dynamic Active/Active/Standby Load Balancing

Can I assume that DB A, DB B, and Archive are three SEPARATE services/pools, and can I also assume they are attached to three separate virtual servers as well? If they are separate pools, then priority group load balancing allows you to assign different priorities to members of a pool. On the Members tab of a given pool, set the Priority Group Activation option to something like Less than 1. Then click each of the member nodes and set a priority group number. So for example, set servers 1, 2, 3, 4, and 5 to priority 2 (higher numbers mean higher priority), and set servers 6, 7, and 8 to priority 1. With this setting, only the priority 2 (higher) members will be used until all (less than 1) priority 2 members become unavailable (per pool). You'll also of course need a monitor on the pools to determine that availability.