What is the debug ip ospf specific command to see the route receive event?

ปลาวาฬทราย RMUTT CPE IX · ‎11-30-2020

I'm facing the issue that another vendor device doesn't advertise the OSPF routes to my core HQ router. I'm afraid that if I turn on the debug command, it will impact my services. Do you have any suggest specific command to debug when another side re-advertise the OSPF routes.

Thank you very much.

marce1000 · ‎11-30-2020

- Check if this can be useful :

https://www.ccexpert.us/routing-table/using-ospf-debug-commands.html#:~:text=To%20display%20information%20about%20each,command%20disables%20the%20debugging%20output.

M.

-- Each morning when I wake up and look into the mirror I always say ' Why am I so brilliant ? '
When the mirror will then always repond to me with ' The only thing that exceeds your brilliance is your beauty! '

Georg Pauwen · ‎11-30-2020

Hello,

what vendor/model is trying to advertise the OSPF ? Typically, it is an OSPF MTU mismatch. On your (the Cisco side), try the 'ip ospf mtu-ignore' command...

ปลาวาฬทราย RMUTT CPE IX · ‎11-30-2020

Topology:

Spoiler

I'm trying lab. Main link is 10.10.3.0/30. Actually, my customer claims that their R1 didn't get the routes from 10.10.10.2. So, they won't have a backup path, but I wonder how OSPF can see the backup route?

Thank you very much.

paul driver · ‎12-01-2020

Hello

post the output of the below command in a file and attached to this post:

sh ip ospf neigbours

sh ip ospf interface brief

sh ip ospf database

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Kind Regards
Paul

ปลาวาฬทราย RMUTT CPE IX · ‎12-01-2020

sh ip ospf neigbours & sh ip ospf interface brief:

Spoiler

sh ip ospf database:

Spoiler

Thank you very much.

pigallo · ‎12-01-2020

Hi,

@ปลาวาฬทราย RMUTT CPE IX wrote:

I'm trying lab. Main link is 10.10.3.0/30. Actually, my customer claims that their R1 didn't get the routes from 10.10.10.2. So, they won't have a backup path, but I wonder how OSPF can see the backup route?

actually Ospf will always install the SPF in its rib.To see a backup route installed in the rib you should use OSPF LFA feature if this is your final goal.

Instead if you want just examine remote LSAs, you better query your 3rd party neighbor node database with the following command to see if 5.5.5.5 LSA is present. You can issue the command from R1 cli.

show ip ospf database adv-router 172.16.1.253

you can post the output if you want.

I can give a try and help you troubleshoot the issue.

Regards.