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BGP routing table

I advertised several internal subnets (10.10.1.0/24, 10.10.2.0/24, & 10.10.3.0/24) to my provider. I have a Cisco router and I am trying to understand the sh ip route with BGP. I see my subnets as internal but I also see 10.10.0.0/16 with path AS as 65003 and next hop the interface of the other router. So does it mean that the other router advertises the 10.10.0.0/16 to me?

My AS is 65010.

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0/0 10.10.200.1 0 0 65003 13999 ?
*> 10.10.0.0/16 10.10.200.1 0 0 65003 ?
*> 10.10.1.0/24 0.0.0.0 100 32768 i
*> 10.10.2.0/24 0.0.0.0 100 32768 i
*> 10.10.3.0/24 0.0.0.0 100 32768 i

ASKER CERTIFIED SOLUTION

pergr

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leblanc

ASKER

That's what I thought and they guarantee me that they did not advertise the 10.2.0.0/16 to us. I will have to configure the soft command to be able to do the show received-routes. This is a Fortinet FW so I have to look for the command syntax. Thx

SOLUTION

giltjr

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pergr

In the first post you said it is a Cisco, and now a FortiGate. Are both involved?

leblanc

ASKER

Sorry for the confusion. It is actually a Fortigate.

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mikebernhardt

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leblanc

ASKER

Yes. I told them to check and they say they do not advertise that network. So we have a leak route somewhere in their router then. I am supposed to advertise that network because it is from my LAN.

pergr

I assume this is an MPLS VPN, where you also have other sites.
Is it not possible that you are advertising that /16 from another site?

Did you try to clear the BGP session, and see if the /16 is there again when the session comes back up?
If it is, for sure the provider will be able to see where they are getting it from.

leblanc

ASKER

This is a new site with a new subnet on MPLS VPN. We did clear the session several times. I will reopen the ticket.

SOLUTION

giltjr

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mikebernhardt

Please post the BGP portion of your router configuration.

leblanc

ASKER

The problem was their interface was configured as /16 instead of /30.

mikebernhardt

I guess that would do it :-)