Ospf Policy Attach Points; Default-Information Originate; Redistribute - Cisco ASR 9000 Series Routing Configuration Manual

Implementing Routing Policy

OSPF Policy Attach Points

This section describes each of the OSPF policy attach points and provides a summary of the OSPF attributes
and operators.

Default-Information Originate

The default-information originate attach point allows the user to conditionally inject the default route 0.0.0.0/0
into the OSPF link-state database, which is done by evaluating the attached policy. If any routes in the local
RIB pass the policy, then the default route is inserted into the link-state database.
The following example shows how to generate a default route if any of the routes that match 10.0.0.0/8 ge 8
le 25 are present in the RIB:
route-policy ospf-originate
if rib-has-route in (10.0.0.0/8 ge 8 le 25) then
pass
endif
end-policy
router ospf 1
default-information originate policy ospf-originate
.
.
.

Redistribute

The redistribute attach point within OSPF injects routes from other routing protocol sources into the OSPF
link-state database, which is done by selecting the routes it wants to import from each protocol. It then sets
the OSPF parameters of cost and metric type. The policy can control how the routes are injected into OSPF
by using the set metric-type or set ospf-metric command.
The following example shows how to redistribute routes from IS-IS instance instance_10 into OSPF instance
1 using the policy OSPF-redist. The policy sets the metric type to type-2 for all redistributed routes. IS-IS
routes with a tag of 10 have their cost set to 100, and IS-IS routes with a tag of 20 have their OSPF cost set
to 200. Any IS-IS routes not carrying a tag of either 10 or 20 are not be redistributed into the OSPF link-state
database.
route-policy OSPF-redist
set metric-type type-2
if tag eq 10 then
set ospf cost 100
elseif tag eq 20 then
set ospf cost 200
else
drop
endif
end-policy
router ospf 1
redistribute isis instance_10 policy OSPF-redist
.
.
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Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
Attach Points
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