Configure Ospf To Import Routes Of Other Protocols - Huawei Quidway S3500 Series Operation Manual

Operation Manual - Routing Protocol
Quidway S3500 Series Ethernet Switches
Specify the key-id and key for OSPF MD5
authentication
Disable
authentication
By default, the interface is not configured with either simple authentication or MD5
authentication.

4.2.21 Configure OSPF to import Routes of Other Protocols

The dynamic routing protocols on the router can share the routing information. As far as
OSPF is concerned, the routes discovered by other routing protocols are always
processed as the external routes of AS. In the import-route commands, you can
specify the route cost type, cost value and tag to overwrite the default route receipt
parameters (refer to "Configure Parameters for OSPF to import External Routes").
The OSPF uses the following four types of routes (in priority):
Intra-area route
Inter-area route
External route type 1
External route type 2
Intra-area and inter-area routes describe the internal AS topology whereas the external
routes describes how to select the route to the destinations beyond the AS.
The external routes type-1 refer to the imported IGP routes (such as static route and
RIP). Since these routes are more reliable, the calculated cost of the external routes is
the same as the cost of routes within the AS. Also, such route cost and the route cost of
the OSPF itself are comparable. That is, cost to reach the external route type 1 = cost to
reach the corresponding ASBR from the local router + cost to reach the destination
address of the route from the ASBR
The external routes type-2 refer to the imported EGP routes. Since these routes have
lower credibility, OSPF assumes that the cost spent from the ASBR to reach the
destinations beyond the AS is greatly higher than that spent from within the AS to the
ASBR. So in route cost calculation, the former is mainly considered, that is, the cost
spent to reach the external route type 2 = cost spent to the destination address of the
route from the ASBR. If the two values are equal, then the cost of the router to the
corresponding ASBR will be considered.
Perform the following configuration in OSPF view.
Operation
the interface to
Huawei Technologies Proprietary
ospf authentication-mode md5
key_id key
use MD5 undo ospf authentication-mode
md5
4-18
Chapter 4 OSPF Configuration
Command