Trouble shooting OSPF Routing Flapping
Hi,
I am labbing on a keith Barker lab for OSPF( Cisco PT OSPF / Tshoot 2020-06-18). I managed to get the tasks in the labbing resolved ( or so I believed ) . I have a issue with OSPF flapping where the adjacency is unstable. It's the int g0/0 interface connected to the MLS. I tried changing the network type to point to point. It's still flapping. I tried shutting off the router and turning it back on, same issue. I checked the timers, all seem correct.
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Can someone please help me with this issue or point me in the direction of where keith barker may have labbed this? I tried searching for it on youtube. I cannot find the video.
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Thanks
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R2(config-if)#do show ip ospf int g0/0
GigabitEthernet0/0 is up, line protocol is up
Internet address is 10.12.0.2/24, Area 0
Process ID 1, Router ID 10.24.0.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.30.0.1, Interface address 10.12.0.1
Backup Designated Router (ID) 10.24.0.2, Interface address 10.12.0.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 3/3, 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 10.30.0.1 (Designated Router)
Suppress hello for 0 neighbor(s)
\---------------------
Ran a debug ip ospf adj
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03:34:37: OSPF: Build router LSA for area 0, router ID 10.24.0.2, seq 0xffffffff80000068
03:34:37: OSPF: Build router LSA for area 0, router ID 10.24.0.2, seq 0xffffffff80000069
03:34:37: OSPF: Send DBD to 10.30.0.1 on GigabitEthernet0/0 seq 0x163db3c7 opt 0x00 flag 0x0 len 32
R2(config-if)#
03:35:17: %OSPF-5-ADJCHG: Process 1, Nbr 10.30.0.1 on GigabitEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
03:35:17: %OSPF-5-ADJCHG: Process 1, Nbr 10.30.0.1 on GigabitEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
03:35:17: OSPF: Build router LSA for area 0, router ID 10.24.0.2, seq 0xffffffff80000069
03:35:17: OSPF: DR/BDR election on GigabitEthernet0/0
03:35:17: OSPF: Elect BDR 10.24.0.2
03:35:17: OSPF: Elect DR 10.24.0.2
03:35:17: OSPF: Elect BDR 0.0.0.0
03:35:17: OSPF: Elect DR 10.24.0.2
03:35:17: DR: 10.24.0.2 (Id) BDR: none
03:35:17: OSPF: Build router LSA for area 0, router ID 10.24.0.2, seq 0xffffffff8000006a
03:35:17: OSPF: No full nbrs to build Net Lsa for interface GigabitEthernet0/0
03:35:17: OSPF: Send DBD to 10.30.0.1 on GigabitEthernet0/0 seq 0x33979633 opt 0x00 flag 0x7 len 32
03:35:17: OSPF: DR/BDR election on GigabitEthernet0/0
03:35:17: OSPF: Elect BDR 0.0.0.0
03:35:17: OSPF: Elect DR 10.30.0.1
03:35:17: OSPF: Elect BDR 10.24.0.2
03:35:17: OSPF: Elect DR 10.30.0.1
03:35:17: DR: 10.30.0.1 (Id) BDR: 10.24.0.2 (Id)
03:35:17: OSPF: Build router LSA for area 0, router ID 10.24.0.2, seq 0xffffffff8000006a
03:35:17: OSPF: Rcv DBD from 10.30.0.1 on GigabitEthernet0/0 seq 0x163db3c8 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART