[outages] Peering issue between Cogent and Tata?

[Job Snijders]

Hi Robert, others,

On Tue, Jan 10, 2023 at 05:23:58PM +0000, Robert Heuvel via Outages wrote:
> That is a Route Validation issue.

I'm not sure it is!

> The IP 35.209.30.41 is part of 35.208.0.0/15 for which a ROA has been
> created by AS15169 to be originated by AS15169.
>
> If check the IP on the Cogent looking glass, Cogent shows that the IP
> is coming from AS19527 (which is not correct according to the ROA for
> this prefix…

There are two ROAs for this prefix, one authorising 15169 and the
other authorising 19527:

19527: https://console.rpki-client.org/rpki.arin.net/repository/arin-rpki-ta/5e4a23ea-e80a-403e-b08c-2171da2157d3/746e0111-fafb-430f-b778-d204cfcd99a8/8314711c-e263-425a-adda-3995b7095d9d/07879125-74b8-3a42-b7b0-80fdd7b7a73f.roa.html

15169: https://console.rpki-client.org/rpki.arin.net/repository/arin-rpki-ta/5e4a23ea-e80a-403e-b08c-2171da2157d3/746e0111-fafb-430f-b778-d204cfcd99a8/8314711c-e263-425a-adda-3995b7095d9d/ca819b63-a4f5-312d-a544-77c183e52a22.roa.html

The RFC 6811 BGP route validation algorithm only requires a single (one)
ROA to set the state of the route as "valid". Multiple ROAs for the same
prefix do not conflict with each other.

Kind regards,

Job