Dell S4048T-ON, Configuration Manual

Page: 633 / 1146

Process ID 1, Router ID 11.1.2.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 13.1.1.1, Interface address 10.2.3.2
Backup Designated Router (ID) 11.1.2.1, Interface address 10.2.3.1
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 13.1.1.1 (Designated Router)
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Loopback interfaces also help the OSPF process. OSPF picks the highest interface address as the router-id and a Loopback interface
address has a higher precedence than other interface addresses.
Example of Viewing OSPF Status on a Loopback Interface
Dell#show ip ospf 1 int
TenGigabitEthernet 1/23 is up, line protocol is up
Internet Address 10.168.0.1/24, Area 0.0.0.1
Process ID 1, Router ID 10.168.253.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.168.253.5, Interface address 10.168.0.4
Backup Designated Router (ID) 192.168.253.3, Interface address 10.168.0.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Neighbor Count is 3, Adjacent neighbor count is 2
Adjacent with neighbor 10.168.253.5 (Designated Router)
Adjacent with neighbor 10.168.253.3 (Backup Designated Router)
Loopback 0 is up, line protocol is up
Internet Address 10.168.253.2/32, Area 0.0.0.1
Process ID 1, Router ID 10.168.253.2, Network Type LOOPBACK, Cost: 1
Loopback interface is treated as a stub Host.
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Configuring Stub Areas
OSPF supports different types of LSAs to help reduce the amount of router processing within the areas.
Type 5 LSAs are not flooded into stub areas; the ABR advertises a default route into the stub area to which it is attached. Stub area routers
use the default route to reach external destinations.
To ensure connectivity in your OSPFv2 network, never configure the backbone area as a stub area.
To configure a stub area, use the following commands.
1 Review all areas after they were configured to determine which areas are NOT receiving type 5 LSAs.
EXEC Privilege mode
show ip ospf process-id [vrf] database database-summary
2 Enter CONFIGURATION mode.
EXEC Privilege mode
configure
3 Enter ROUTER OSPF mode.
CONFIGURATION mode
router ospf process-id [vrf]
Process ID is the ID assigned when configuring OSPFv2 globally.
4 Configure the area as a stub area.
Open Shortest Path First (OSPFv2 and OSPFv3) 633