As part of my work on the original Cisco: The Complete Reference book, I created a route processing flow chart for EIGRP’s DUAL Finite State Machine. This ultimately did not make it into the book in its original form, as it was way too big. However, I always found it helpful (and strangely beautiful, in a geeky kind of way), and thought I would post it up to world in the hopes that it helps folks understand EIGRP.

EIGRP DUAL Route Processing Flow Chart

For those who are interested, I have also included a link to a high quality poster print, available through my Zazzle store.

Poster Print