You should not have overlapping IP space assigned to interfaces anywhere in your network. When you try to do this on two interfaces on the same router, you'll get the message you mentioned.IP addresses should be unique across all devices and interfac...
You might have some strange traffic flows if you turn off ip route cache. I believe that load balancing will then be done on a per-packet basis. So for each network flow (ftp session, http session, etc), You'll have half the packets going over each l...