the route is not in our bgprouter

Deric Kwok deric.kwok2000 at
Wed Oct 26 01:49:05 UTC 2011


Our upstream provider said that destination network is blocking our ip.

Now my question is how we can know it

If this network is blocking us, the traceroute should reach out our
bgp router to go further nodes before that network, right

2nd question is how they block us to not allow the route to advertise
from our upstream to our bgp router.
ls it possible?

Thank you so much

On Tue, Oct 25, 2011 at 9:35 AM, Patrick Sumby
<patrick.sumby at> wrote:
> If your provider has a looking glass then that is a good start to see if
> they have the route in their routing tables. is a
> good start for searching for a looking glass on their website.
> Have you checked to see if you're actually recieving the route? You may be
> getting the route but not installing it into your routing table for some
> reason (eg invalid next hop or a router from another provider is being
> prefered). Do you have prefix lists inbound from your provider that could be
> blocking a route?
> show ip route X.X.X.X
> and
> show ip bgp route X.X.X.X
> will give different information.
> If you've covered the above and not found the answer then try talking to
> your provider.
> Regards
> Patrick
> On 25/10/2011 13:26, Deric Kwok wrote:
>> Hi
>> When we try to reach to outside ip, this route doesn't have in our bgp
>> router
>> How can we check whether it doesn't advertise from our upstream to us?
>> Any web site and tools can help?
>> Thank you

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