BGP prefix filter list

Karsten Elfenbein karsten.elfenbein at
Wed May 15 16:23:26 UTC 2019


did you find
? It has further links at the end as well.
If you hit the 768k issue for IPv4 you might look at IPv6 as well as
there might be a 64k limit on some tcam profiles. If there is no IPv6
in use (very sad face) there might be the option to switch to a 1m
IPv4 route profile.

Using a default route might influence Reverse Path Forwarding on the
device. But you can apply outbound ACL on upstream ports as well.

The weekly routing table report has lists of worst offenders when it
comes to de aggregation or


Am Mi., 15. Mai 2019 um 13:45 Uhr schrieb Baldur Norddahl
<baldur.norddahl at>:
> Hello
> This morning we apparently had a problem with our routers not handling
> the full table. So I am looking into culling the least useful prefixes
> from our tables. I can hardly be the first one to take on that kind of
> project, and I am wondering if there is a ready made prefix list or similar?
> Or maybe we have a list of worst offenders? I am looking for ASN that
> announces a lot of unnecessary /24 prefixes and which happens to be far
> away from us? I would filter those to something like /20 and then just
> have a default route to catch all.
> Thanks,
> Baldur

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