05-18-2007 05:17 AM - edited 03-03-2019 05:02 PM
Hi, I have configured my router to run OSPF and established adj with other routers (thru switch). However there are 2 routers that wont established the adj. It keep appears below log. It is in the same network/subnet. The MTU is 1500. What is other posibble things to check?
FastEthernet5/0/0 from 2WAY to DOWN, Neighbor Down: Interface down or detached
05-18-2007 05:22 AM
Mazlan,
Check the cable connection to fastethernet 5/0/0. There may be a speed/duplex issue which is causing the interface to go down and thus breaking your adjacency
HTH, rate if it does
Narayan
05-18-2007 05:29 AM
Narayan,
The connection is up. This interface also established ospf neigbor with other routers except 2 router. It keep stuck in exchange state. Also have check the MTU. It is same for all routers connected.
05-18-2007 05:35 AM
Mazlan,
If all the four routers are connected to a LAN segment, OSPF would choose a DR and BDR and all the routers would establish adjacencies only with these 2 routers.
But the status of the routers would not be in exchange but in a stae of 2-way..
Can you post your configurations
HTH, rate if it does
Narayan
05-18-2007 05:32 AM
HI Mazlan, [Pls Rate if Helps]
After creating / "Changing" a OSPF router id inorder to take effect you need to reload the router / reset the ospf process. Pls try cmd below:
#clear ip ospf process
Reset All OSPF Process[n]:yes
#show ip ospf neighbor
Pls Rate if Helps ! !
Best Regards,
Guru Prasad R
05-18-2007 05:37 AM
Hi guruprasadr,
Why I need to change router ID. This router has established neigbor with other routers as well. However i have tried this but still same. :(
--mazlan
05-18-2007 05:43 AM
Would it be possible for you to paste the sh ip ospf neighbors from all the 4 routers
Narayan
05-18-2007 05:44 AM
HI Mazlan,
Try this command twice / thrice. Can you please check by rebooting the router.
Number of LSA's should be same on all the Routers.Check with "show ip ospf database database-summary" cmd to observe.
Check "show ip ospf database" to check the LSA's on all routers.
Pls Rate if Helps ! !
Best Regards,
Guru Prasad R
05-18-2007 05:53 AM
Hi Prasad,
Thank you. I have check the number of LSA and it is same througout the network.
Area 0 database summary
LSA Type Count Delete Maxage
Router 116 0 0
Network 30 0 0
Summary Net 2393 0 0
Summary ASBR 269 0 0
Type-7 Ext 0 0 0
Prefixes redistributed in Type-7 0
Opaque Link 0 0 0
Opaque Area 4 0 0
Subtotal 2812 0 0
05-18-2007 05:58 AM
HI Mazlan,
Whether this solved your Issue. Can you pls confirm / post the configuration.
Pls Rate if Helped you to identify / solve.
Best Regards,
Guru Prasad R
05-18-2007 01:44 PM
Have you checked BFD, Fast Failure Detection to Speed Network Convergence
Check the following article:http://www.cisco.com/en/US/tech/tk365/technologies_white_paper0900aecd80244005.shtml
HTH: Steve
05-21-2007 12:52 AM
I have checked seems everything is ok. excpt it still wont established neigborship.. below logs keeps appears. have run debug i osf adj, the mtu is 1500.. any ideas??
May 21 16:47:50.754: %OSPF-5-ADJCHG: Process 1, Nbr 61.6.191.77 on GigabitEthernet0/0/0 from DOWN to DOWN, Neighbor Down: Dead timer expired
61.6.163.160 for invalid RP 161.142.158.14
May 21 16:49:11.431: %OSPF-5-ADJCHG: Process 1, Nbr 61.6.191.77 on GigabitEthernet0/0/0 from EXSTART to DOWN, Neighbor Down: Too many DBD retransmitions
Debup output:
May 21 16:51:32.417: OSPF: Retransmitting DBD to 61.6.191.77 on GigabitEthernet0/0/0
May 21 16:51:32.417: OSPF: 61.6.191.77 address 161.142.173.70 on GigabitEthernet0/0/0 is dead, state DOWN
May 21 16:51:32.417: %OSPF-5-ADJCHG: Process 1, Nbr 61.6.191.77 on GigabitEthernet0/0/0 from EXSTART to DOWN, Neighbor Down: Too many DBD retransmitions
May 21 16:51:33.388: OSPF: Nbr 61.6.191.77 161.142.173.70 GigabitEthernet0/0/0 is currently ignored
May 21 16:51:35.926: OSPF: Nbr 61.6.191.77 161.142.173.70 GigabitEthernet0/0/0 is currently ignored
May 21 16:51:38.641: OSPF: Nbr 61.6.191.77 161.142.173.70 GigabitEthernet0/0/0 is currently ignored
May 21 16:51:43.096: OSPF: Nbr 61.6.191.77 161.142.173.70 GigabitEthernet0/0/0 is currently ignored
05-21-2007 04:41 AM
Mazlan,
Can you try configuring "no capability lls" to see if it makes a difference.
Hope this helps,
05-21-2007 05:13 AM
Harold,
I have tried but still same. This router wont established neibor with one router.
It keep stuck at exstart state.
05-21-2007 05:15 AM
Mazlan,
Can you run a "deb ip ospf adj" on the opposite router as well.
Thanks,
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