Seed Metric
Redistribution involves configuring a routing protocol to advertise routes
learned by another routing process. Normally, protocols base their metric on
an interface value, such as bandwidth, but no interface for a redistributed
route exists. Protocols use incompatible metrics, so the redistributed routes
must be assigned a new metric compatible with the new protocol.
A route’s starting metric is called its seed metric. Set the seed metric for all
redistributed routes with the default-metric [metric] command under the
routing process. To set the metric for specific routes, either use the metric
keyword when redistributing or use the route-map keyword to link a route
map to the redistribution. After the seed metric is specified, it increments
normally as the route is advertised through the network (except for certain
OSPF routes).