A default seed metric with the value of infinity is assigned to Open Shortest Path First(OSPF) routes that are redistributed into Enhanced Interior Gateway Routing Protocol (EIGRP). Routes with an infinite metric are ignored by EIGRP and are not entered into the routing table. There is no direct translation of the OSPF cost-based metric into an EIGRP-equivalent metric; the EIGRP metric is based on bandwidth, delay, reliability, and load. Because the OSPF metric cannot be automatically converted into a metric that EIGRPunderstands, EIGRP requires that the metric be defined for all redistributed routes before those routes are entered into the routing table. To assign a default metric for routes redistributed into EIGRP, you should issue the defaultmetric bandwidth delay reliability loading mtu command. To assign a metric to an individual route redistributed from OSPF into EIGRP, you should issue the redistribute ospfprocessidmetric bandwidth delay reliability loading mtu command.
A default seed metric of infinity is also assigned to routes that are redistributed into Routing Information Protocol (RIP). Like EIGRP, RIP requires that the metric be defined for all redistributed routes before those routes are entered into the routing table. RIP uses hop count as a metric. Valid hopcount values are from 1 through 15; a value of 16 is considered to be infinite. The hopcount metric increases by 1 for each router along the path. Cisco recommends that you set a low value for the hopcount metric for redistributed routes. To assign a default metric for routes redistributed into RIP, you should issue the defaultmetric hopcount command. To assign a metric to an individual route redistributed into RIP, you should issue the redistribute protocolhopcount command. If no metric is assigned during redistribution and no default metric is configured for RIP, the routes are assigned an infinite metric and are ignored by RIP.
A default seed metric of 0 is assigned to routes that are redistributed into IntermediateSystemtoIntermediate System (ISIS). ISIS uses a cost metric assigned to each participating interface. ISIS prefers routes with the lowest cost. Routes redistributed into IS-IS are designated as Level 2 routes unless otherwise specified.
A default seed metric of 1 is assigned to Border Gateway Protocol (BGP) routes that are redistributed into OSPF. OSPF uses a cost metric based on the bandwidth of each participating interface and prefers internal routes with the lowest cost. By default, all routes redistributed into OSPF are designated as Type 2 external (E2) routes. E2 routes have a metric that remains constant throughout the routing domain. Alternatively, routes redistributed into OSPF can be designated as Type 1 external (E1) routes. With E1 routes, the internal cost of the route is added to the initial metric assigned during redistribution.
A default seed metric of 20 is assigned to routes that are redistributed into OSPF from an internal gateway protocol other than OSPF. When OSPF routes are redistributed from one OSPF routing process to another OSPF routing process, the metrics are preserved and no default seed metric is assigned. Metrics are also preserved when routes are redistributed from one Interior Gateway Routing Protocol (IGRP) or EIGRP routing process into another IGRP or EIGRP routing process.