Wrong /24 Announcement at UU.net / BGP IOS Bug ?

[Winfried Haug <haug () seicom net>]

Hello..

one of our customers (germany.net, AS6751) is announcing us
151.189.0.0/16. We announce this to our both upstreams 
ECRC (AS1273) and Ebone (1755).

Since a few days a lot of german ISPs ask us, why 151.189.0.0/24
is routed via UU.net to the USA and then goes back to germany.

We checked our cisco-routers an finaly i found a Customer of UU.net
with a looking glass: (http://zeus.lyceum.com/cgi-bin/nph-bgp-routes)

> QUERY: bgp 151.189.0.0
> FROM: BR1.ATL1.lyceum.net.
>
> BGP routing table entry for 151.189.0.0/24, version 9891827
> Paths: (1 available, best #1, advertised over IBGP)
>   701 1800 1755 1755 1755 5549 5549 6751
>     157.130.64.121 from 157.130.64.121 (137.39.2.42)
>       Origin IGP, valid, external, best

ok lets see bacK: 

Sprint (1800) doesnt have this /24 but the /16 as it should be:

icm-bb4-pen#show ip bgp 151.189.0.0 255.255.255.0
% Network not in table
icm-bb4-pen#

the same applies to EBONE (AS1755):

frankfurt-ebs1>show ip bgp 151.189.0.0 255.255.255.0
% Network not in table
frankfurt-ebs1>


an we (AS5549) also dont see any /24 out of 151.189.0.0/16

So the question is: why does UU.net announce 151.189.0.0/24 and from
where do they get it. The worse thing is, that all uu.net customers get
this )(&%&$()& /24 from the hub in Frankfurt. The Space 
151.189.1.0 - 151.189.255.255 is visiable at uu.net via 151.189.0.0/16..

So what happens here, could this be an ios bug ?

We didnt touch our configuration towards ebone and they dont play
with their configuration every day :-) 

Any ideas ? hints ?

Winfried

PS: for the german isps, we fixed it by announcing only at de-cix the
    151.189.0.0/24 additionally to 151.189.0.0/16 and it works, but
    i am still looking for an answer to my questions :-) ?



-- 

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