3Com S7902E, Configuration Manual

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10.3.1.0/24 10 Transit 10.3.1.2 10.3.1.1 0.0.0.2
10.4.1.0/24 25 Inter 10.3.1.1 10.3.1.1 0.0.0.2
10.5.1.0/24 10 Stub 10.5.1.1 10.5.1.1 0.0.0.2
10.1.1.0/24 12 Inter 10.3.1.1 10.3.1.1 0.0.0.2
Routing for ASEs
Destination Cost Type Tag NextHop AdvRouter
3.1.2.0/24 1 Type2 1 10.3.1.1 10.4.1.1
Total Nets: 6
Intra Area: 2 Inter Area: 3 ASE: 1 NSSA: 0
Configuring OSPF to Advertise a Summary Route
Network requirements
As shown in the following figure:
z
Switch A and Switch B are in AS 200, which runs OSPF.
z
Switch C, Switch D, and Switch E are in AS 100, which runs OSPF.
z
An eBGP connection is established between Switch B and Switch C. Switch C is configured to
redistribute OSPF routes into BGP.
z
Switch B is configured to redistribute BGP routes into OSPF. Switch B is configured with route
summarization and advertises only the summary route 10.0.0.0/8 to reduce Switch A's routing table
size.
Figure 1-23 Network diagram for OSPF summary route advertisement
Configuration procedure
1) Configure IP addresses for interfaces (omitted)
2) Configure OSPF basic functions
# Configure Switch A.