We're trying to figure out how ZCM load balances when there are 2 primary servers in the same zone.

The documentation suggests that ZCM will load balance out-of-the-box using shortest path rules. In our case, both primary servers are in the same rack and are plugged directly into the network core. Devices should view both primary servers as being the same distance from themselves.

Will clients/devices balance between the 2 primary servers in this set-up without the need of L4 hardware?

By balance, I do not mean fail-over. I would like both servers to share the load. We are running SLES 10 SP2 with ZCM 10.1.3. Both zone servers connect to a remote Oracle DB.