My network is purely EIGRP. From HQ I have two routers. HQ1 and HQ2 connected via a FastEther interface. HQ1 had 3xT1 to another office router RO1. We put in an OC3 circuit between HQ2 and RO1 and try to make this link a primary. Two 3640 routers (HQATM and ROATM) with FastEther (FA) and ATM interface sare used to bridge between ATM and FastEthernet. The topology is
HQ2 --- FA---HQATM---OC3---ROATM---FA---RO1
When I turn the ATM on, traffic from HQ2 were sent to HQATM with BW of 100 Mbps and hop count is 3. But 20 seconds later, traffic went back to is previous route which is from HQ2 to HQ1 to RO1 via the 3xT1 with BW of 1.544 Mbps and hop count is 2.
Is it by default, EIGRP is based on hop count? And if hop counts is equal, then the metric (BW and delay) will determine the best path? Is there way to change the hop count?