Troubleshooting ospf configuration, No ospf neighbor relationship established, Symptom – H3C Technologies H3C SR8800 User Manual

Page 150: Analysis, Solution, Incorrect routing information

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Destination: 120.1.1.0/24

Protocol: OSPF Process ID: 0

Preference: 0 Cost: 2

NextHop: 192.168.0.100 Interface: GigabitEthernet3/1/1

BkNextHop: 0.0.0.0 BkInterface:

RelyNextHop: 0.0.0.0 Neighbor : 0.0.0.0

Tunnel ID: 0x0 Label: NULL

State: Invalid Adv Age: 00h58m05s

Tag: 0

Troubleshooting OSPF configuration

No OSPF neighbor relationship established

Symptom

No OSPF neighbor relationship can be established.

Analysis

If the physical link and lower layer protocols work well, check OSPF parameters configured on interfaces.

Two neighbors must have the same parameters, such as the area ID, network segment and mask (a P2P
or virtual link may have different network segments and masks).

Solution

1.

Display OSPF neighbor information using the display ospf peer command.

2.

Display OSPF interface information using the display ospf interface command.

3.

Ping the neighbor router’s IP address to check connectivity.

4.

Check OSPF timers. The dead interval on an interface must be at least four times the hello interval.

5.

On an NBMA network, using the peer ip-address command to specify the neighbor manually is
required.

6.

On an NBMA or a broadcast network, at least one connected interface must have a router priority
higher than 0.

Incorrect routing information

Symptom

OSPF cannot find routes to other areas.

Analysis

The backbone area must maintain connectivity to all other areas. If a router connects to more than one

area, at least one area must be connected to the backbone. The backbone cannot be configured as a
Stub area.
In a Stub area, all routers cannot receive external routes, and all interfaces connected to the Stub area

must belong to the Stub area.

Solution

1.

Use the display ospf peer command to display neighbors.

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