I have three routers in this scenario (that matter).

Routes are for A-B-C and A-C

By default with costs of 10 for each route, all traffic from A going to C (and vise versa) go direct and not through B because the cost is 20 with 2 hops instead of 10 with one hop.

I have taken the costs from A-C and C-A and made them 20, or equal to the two hop A-B-C route.

I have observed that this effectively load balances the traffic fairly evenly using the two equal cost routes. My question is this... Is the load balancing handled packet by packet randomly or is there some smarter connection oriented decision making going on? I ask because I have seen a few spikes of traffic only on one route or the other that would not show up if every other packet was sent out the other path.

Is it purely random or is there more to it? Thanks for your time in answering this for me.

Scott

You can read how it works in manual:
http://www.mikrotik.com/testdocs/ros/2.9/ip/route.php
Check out ECMP section.

The document you referred me to is about gateway load balancing with route commands. My question only involves ospf equal cost routing between two routers without the need for a gateway.

Scott

It works the same as ECMP. Connections are chosen for each new source/destination IP pair.