Nokia Network Voyager, Справочное руководство, Страница: 279 / 700

Voyager Reference Guide 279
The rank value is an arbitrarily assigned value used to determine the order of
routes to the same destination in a single routing database. Each route has
only one rank associated with it, even though rank can be set at many places
in the configuration. The route derives its rank from the most specific route
match among all configurations.
The active route is the route installed into the kernel forwarding table by the
routing subsystem. In the case where the same route is contributed by more
than one protocol, the one with the lowest rank becomes the active route.
Some protocols—BGP and aggregates—allow for routes with the same rank.
To choose the active route in these cases a separate tie-breaker is used. This
tie-breaker is called
LocalPref for BGP and weight for aggregates.
Rank Assignments
A default rank is assigned to each protocol. Rank values range from 0-255,
with the lowest number indicating the most preferred route.
The table below summarizes the default rank values.
Preference of Default
Interface routes 0
OSPF routes 10
Static routes 60
IGRP routes 80
RIP routes 100
Aggregate routes 130
OSPF AS external routes 150
BGP routes 170