Learn Linux CCNA CEH IPv6 Cyber-Security Online

Here in this article we will learn to troubleshoot OSPF routing protocols.In previous article we have learnt how to configure ospf routing protocol.And now in this section we will learn how to troubleshoot ospf routing protocol and to do so we have taken example lab of our previous LAB in which i have shown you ospf configuration.In this tutorial we will learn how to troubleshoot  and display ip route,routing table,ospf neighbors detail,parameters of protocols running on the routers,ospf information related to routers interfaces,ospf states,ospf events,ospf packets,border and boundary router information.

 

At Present I am on Router0:

NOW LEARN HOW TO DISPLAY COMPLETE IP ROUTING TABLE:

R2#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
 D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
 N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
 i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
 * - candidate default, U - per-user static route, o - ODR
 P - periodic downloaded static route

Gateway of last resort is not set

O 211.146.0.0/24 [110/2] via 211.146.1.1, 00:50:27, FastEthernet0/0
C 211.146.1.0/24 is directly connected, FastEthernet0/0
C 211.146.2.0/24 is directly connected, Serial0/0/0
O 211.146.3.0/24 [110/128] via 211.146.2.2, 00:50:47, Serial0/0/0
O 211.146.4.0/24 [110/140] via 211.146.2.2, 00:50:17, Serial0/0/0
O 211.146.5.0/24 [110/65] via 211.146.2.2, 00:50:27, Serial0/0/0
O 211.146.6.0/24 [110/66] via 211.146.2.2, 00:50:27, Serial0/0/0
O 211.146.7.0/24 [110/76] via 211.146.2.2, 00:50:17, Serial0/0/0
O 211.146.8.0/24 [110/141] via 211.146.2.2, 00:50:17, Serial0/0/0
O 211.146.9.0/24 [110/142] via 211.146.2.2, 00:50:17, Serial0/0/0

 

How to display  parameters for all protocols running on the router.

 

R2#show ip protocols

Routing Protocol is "ospf 2"
 Outgoing update filter list for all interfaces is not set 
 Incoming update filter list for all interfaces is not set 
 Router ID 211.146.2.1
 Number of areas in this router is 1. 1 normal 0 stub 0 nssa
 Maximum path: 4
 Routing for Networks:
 211.146.1.0 0.0.0.255 area 0
 211.146.2.0 0.0.0.255 area 0
 Routing Information Sources: 
 Gateway Distance Last Update 
 211.146.1.1 110 00:22:10
 211.146.2.1 110 00:22:10
 211.146.5.1 110 00:22:16
 211.146.6.1 110 00:22:10
 211.146.7.1 110 00:22:10
 211.146.7.2 110 00:22:10
 211.146.8.1 110 00:22:12
 211.146.9.1 110 00:22:10
 Distance: (default is 110)

 

How to display OSPF Routing Process basic information.

R2#show ip ospf
 Routing Process "ospf 2" with ID 211.146.2.1
 Supports only single TOS(TOS0) routes
 Supports opaque LSA
 SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
 Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
 Number of external LSA 0. Checksum Sum 0x000000
 Number of opaque AS LSA 0. Checksum Sum 0x000000
 Number of DCbitless external and opaque AS LSA 0
 Number of DoNotAge external and opaque AS LSA 0
 Number of areas in this router is 1. 1 normal 0 stub 0 nssa
 External flood list length 0
 Area BACKBONE(0)
 Number of interfaces in this area is 2
 Area has no authentication
 SPF algorithm executed 6 times
 Area ranges are
 Number of LSA 13. Checksum Sum 0x068b89
 Number of opaque link LSA 0. Checksum Sum 0x000000
 Number of DCbitless LSA 0
 Number of indication LSA 0
 Number of DoNotAge LSA 0
 Flood list length 0

 

How to display  a detailed list of ospf neighbors 

R2#show ip ospf neighbor detail 
 Neighbor 211.146.5.1, interface address 211.146.2.2
 In the area 0 via interface Serial0/0/0
 Neighbor priority is 0, State is FULL, 6 state changes
 DR is 0.0.0.0 BDR is 0.0.0.0
 Options is 0x00
 Dead timer due in 00:00:35
 Neighbor is up for 00:57:06
 Index 1/1, retransmission queue length 0, number of retransmission 0
 First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0)
 Last retransmission scan length is 0, maximum is 1
 Last retransmission scan time is 0 msec, maximum is 0 msec
 Neighbor 211.146.1.1, interface address 211.146.1.1
 In the area 0 via interface FastEthernet0/0
 Neighbor priority is 1, State is FULL, 6 state changes
 DR is 211.146.1.2 BDR is 211.146.1.1
 Options is 0x00
 Dead timer due in 00:00:36
 Neighbor is up for 00:57:15
 Index 2/2, retransmission queue length 0, number of retransmission 0
 First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0)
 Last retransmission scan length is 0, maximum is 0
 Last retransmission scan time is 0 msec, maximum is 0 msec

 

Display a brief list of OSPF neighbors.

R2#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
211.146.5.1 0 FULL/ - 00:00:38 211.146.2.2 Serial0/0/0
211.146.1.1 1 FULL/BDR 00:00:38 211.146.1.1 FastEthernet0

 

How to see ospf information related  which relates it with router interfaces.

R2#show ip ospf interface
FastEthernet0/0 is up, line protocol is up
 Internet address is 211.146.1.2/24, Area 0
 Process ID 2, Router ID 211.146.2.1, Network Type BROADCAST, Cost: 1
 Transmit Delay is 1 sec, State DR, Priority 1
 Designated Router (ID) 211.146.2.1, Interface address 211.146.1.2
 Backup Designated Router (ID) 211.146.1.1, Interface address 211.146.1.1
 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
 Hello due in 00:00:04
 Index 1/1, flood queue length 0
 Next 0x0(0)/0x0(0)
 Last flood scan length is 1, maximum is 1
 Last flood scan time is 0 msec, maximum is 0 msec
 Neighbor Count is 1, Adjacent neighbor count is 1
 Adjacent with neighbor 211.146.1.1 (Backup Designated Router)
 Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
 Internet address is 211.146.2.1/24, Area 0
 Process ID 2, Router ID 211.146.2.1, Network Type POINT-TO-POINT, Cost: 64
 Transmit Delay is 1 sec, State POINT-TO-POINT, Priority 0
 No designated router on this network
 No backup designated router on this network
 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
 Hello due in 00:00:04
 Index 2/2, flood queue length 0
 Next 0x0(0)/0x0(0)
 Last flood scan length is 1, maximum is 1
 Last flood scan time is 0 msec, maximum is 0 msec
 Neighbor Count is 1 , Adjacent neighbor count is 1
 Adjacent with neighbor 211.146.5.1
 Suppress hello for 0 neighbor(s)

 

how to display border and boundary router information.

R2#show ip ospf border-routers
OSPF Process 2 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

Display all ospf events

R2#debug ip ospf events
OSPF events debugging is on

01:08:21: OSPF: Rcv hello from 211.146.5.1 area 0 from Serial0/0/0 211.146.2.2

01:08:21: OSPF: End of hello processing

01:08:22: OSPF: Rcv hello from 211.146.1.1 area 0 from FastEthernet0/0 211.146.1.1

01:08:22: OSPF: End of hello processing

01:08:31: OSPF: Rcv hello from 211.146.5.1 area 0 from Serial0/0/0 211.146.2.2

01:08:31: OSPF: End of hello processing

01:08:32: OSPF: Rcv hello from 211.146.1.1 area 0 from FastEthernet0/0 211.146.1.1

01:08:32: OSPF: End of hello processing

 

Display various ospf states.

R1#debug ip ospf adjacency

 

Display OSPF Packets.

R1#debug ip ospf packets