Command Manual – IPv4 Routing
H3C S7500E Series Ethernet Switches
Chapter 3 OSPF Configuration Commands
3-36
OSPF prioritize routes as follows:
z
Intra-area route
z
Inter-area route
z
Type1 External route
z
Type2 External route
An intra-area route is a route in an OSPF area. An inter-area route is between any two
OSPF areas. Both of them are internal routes.
An external route is a route to a destination outside the OSPF AS.
A Type-1 external route is an IGP route, such as RIP or STATIC, which has high
reliability and whose cost is comparable with the cost of OSPF internal routes.
Therefore, the cost from an OSPF router to a Type-1 external route’s destination equals
the cost from the router to the corresponding ASBR plus the cost from the ASBR to the
external route’s destination.
A Type-2 external route is an EGP route, which has low credibility, so OSPF considers
the cost from the ASBR to a Type-2 external route is much bigger than the cost from the
ASBR to an OSPF internal router. Therefore, the cost from an internal router to a
Type-2 external route’s destination equals the cost from the ASBR to the Type-2
external route’s destination.
Related commands:
default-route-advertise.
Note:
z
The
import-route
command cannot redistribute default routes.
z
Use the
import-route bgp allow-ibgp
command with care, because it redistributes
both EBGP and IBGP routes that may cause routing loops.
Examples
# Redistribute routes from RIP process 40 and specify the type, tag, and cost as 2, 33
and 50 for redistributed routes.
<Sysname> system-view
[Sysname] ospf 100
[Sysname-ospf-100] import-route rip 40 type 2 tag 33 cost 50
3.1.30 log-peer-change
Syntax
log-peer-change
undo log-peer-change
