BGP role

[pierky]

Hello,

on the LG, it seems that the Only To Customer (OTC) flag is always set for every prefix across all the peers.
Personally I believe that such piece of information doesn't really provide great value to the overall information offered by the tool, while on the other hand might lead to confusion and misunderstandings.

As far as I understand by looking at the code of the LG and the configuration of the OpenBGPD route collector, this seems not due to a bug in the LG, but rather to the presence of role customer in the config of bgpd.

With that config knob set, the route collector would behave as per the following in most cases:

For backward compatibility, if the BGP Role Capability is sent but one is not received, the BGP Speaker SHOULD ignore the absence of the BGP Role Capability and proceed with session establishment. The locally configured BGP Role is used for the procedures described in Section 5.

Being the local role "customer", the route collector would expect the peer to be a "provider", so the procedure from Section 5 that would be followed is this one:

The following ingress procedure applies to the processing of the OTC Attribute on route receipt:
...
3. If a route is received from a Provider, a Peer, or an RS and the OTC Attribute is not present, then it MUST be added with a value equal to the AS number of the remote AS.

I wonder whether making the route collector transparent to RFC9234 would be a better choice. In that situation, the looking glass would only show OTC attributes which are set downstream and passed along the path.

RFC9234: https://datatracker.ietf.org/doc/html/rfc9234