3.5.d Implement and troubleshoot operations

3.5.d [ii] Topology table, update, query, active, passive

The show ip eigrp topology command displays the EIGRP router ID. The EIGRP router ID comes from the highest IP address assigned to a loopback interface. If no loopback interfaces are configured, the highest IP address assigned to any other active interface is chosen as the router ID. No two EIGRP routers can have the same EIGRP router ID. If they do, you will experience problems exchanging routes between the two routers with equal router IDs.

Route filtering enables routes to be filtered from an EIGRP routing advertisement as they come in from a neighbor or as they are sent out to a neighbor. These filters can cause routes to be missing from the routing table. The show ip protocols command shows whether any filter lists are applied to EIGRP.

Adam, Paul (2014-07-12). All-in-One CCIE V5 Written Exam Guide (Kindle Locations 3162-3163).  . Kindle Edition.