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Day 13 219EIGRP Default RouteThe “quad zero” default static route can be used with any currently supported routing protocols. Inour example, we configure the static default route on R2 because it is simulating a connection toISP. Example 13-9 shows the default static route configuration on R2.Example 13-9Configuring and Redistributing a Default Route in EIGRPR2(config)#ip route 0.0.0.0 0.0.0.0 loopback 1R2(config)#router eigrp 1R2(config-router)#redistribute staticThe redistribute static command tells EIGRP to include this static route in its EIGRP updates toother routers. Example 13-10 shows the routing table for R1 with the default route highlighted.Example 13-10 R1 Routing Table with Default Route InstalledR1#show ip routeCodes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGPD - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter areaGateway of last resort is 172.16.3.2 to network 0.0.0.0192.168.10.0/30 is subnetted, 2 subnetsC 192.168.10.4 is directly connected, Serial0/0/1D 192.168.10.8 [90/2681856] via 192.168.10.6, 00:07:03, Serial0/0/1[90/2681856] via 172.16.3.2, 00:05:58, Serial0/0/0172.16.0.0/16 is variably subnetted, 3 subnets, 2 masksC 172.16.1.0/24 is directly connected, FastEthernet0/0D 172.16.2.0/24 [90/2172416] via 172.16.3.2, 00:05:58, Serial0/0/0C 172.16.3.0/30 is directly connected, Serial0/0/0D EX* 0.0.0.0 [170/2297856] via 172.16.3.2, 00:00:00, Serial0/0/0D 192.168.0.0 [90/2681856] via 192.168.10.6, 00:07:03, Serial0/0/1Modifying the EIGRP MetricEIGRP uses the values bandwidth, delay, reliability, and load in its composite metric to calculatethe preferred path to a network. By default, EIGRP uses only bandwidth and delay in its metriccalculation, as shown in Figure 13-4.The bandwidth metric is a static value assigned by Cisco IOS to interface types. For example, mostserial interfaces are assigned the default value 1544 kbps, the bandwidth of a T1 connection. Thisvalue might or might not reflect the actual bandwidth of the interface.Delay is the measure of time it takes for a packet to traverse a route. The delay metric is a staticvalue based on the type of link to which the interface is connected and is measured in microseconds.