Cisco IP Routing Protocols: Trouble Shooting Techniques (Charles River Media Networking/Security)

IGRP uses a composite metric that is calculated by a combination of delay, bandwidth, reliability, load, and MTU.

The show ip route command displays entries in the IP routing table for the router in which this command is issued.

The show ip protocols command displays filters, parameters, and network information details corresponding to the active routing protocol configured in the router.

The show ip route igrp Number command displays only the IGRP routes in the routing table.

The show interface command displays information about network interfaces within the IGRP network.

The show running-config command displays the current updated operating configuration for IGRP in the router where this command is executed.

The debug ip igrp transaction command lists detailed contents of both sent and received IGRP updates.

The debug ip igrp events command lists summary contents of both sent and received IGRP updates.

The ping ip-addr/hostname command tests the network connectivity with a specified network address.

The undebug all command sets the IGRP debugging system off for the current router.

Misconfiguration problems in IGRP can occur when IGRP routes are missing from the routing table, IGRP is not installing all possible equal cost paths, or if ASN is misconfigured.

The clear ip route * command refreshes the current routing table.

The passive interface command prevents the interface from sending routing updates.

Equal cost path refers to multiple routes to a common destination with same metric values.