EIGRP Feasible Successor Question

BlueUmbrella

Hi. I'm hoping someone is able to answer a question for me. I have read that to qualify as a feasible successor, a router must have an AD less than the FD of the current successor and that this is to help avoid loops. Can anyone please explain why this has to be so and how this avoids creating a loop?

Any help would be much appreciated, thanks!

Ivanjam

EIGRP Loop Prevention Logic « ipSpace.net by @ioshints

EIGRP Feasible Successor Routes - Packet Life

http://www.techexams.net/forums/ccna-ccent/42562-successor-feasible-successor-eigrp.html

IP Routing: Chapter 4: Enhanced Interior Gateway Routing Protocol (EIGRP)

powmia

If a neighboring router says that a route is further away than the route that you currently have... who's to say that neighboring router isn't using YOU as a next hop?

BlueUmbrella

I think I understand it a little more now from the information in your replies. I also found this which helped simplify it.
'If, for a destination, a neighbor router tells us that it is closer to the destination than we have ever been, then this neighbor lies on a loop-free route to this destination.' Thank you, I hope I have this right now!