I was studying the concepts of multi-bird for large environments of IXPs. And, beyond the extra complexity that it brings to the environment, one of the weak points I saw was the fact that all the Bird instances are at the same box(vm, container, etc...).
A friend mentioned that some tests were made with a LoadBalancer redirecting the post-nated connections to other boxes. But even in that scenario, that load balancer would be a single-point-of-failure/bottleneck. So I was remembering Cisco GLBP and Heart-Beat protocol. Those protocols inform different Mac-Addresses to the same IPv4/IPv6 Address, based on the source of the ARP/ND query. Making a load-balance/fail-over based on the glue between layer2 and layer3. P.S.: Several scenarios uses that concept. Corosync, Windows Cluster, Orale RAC, etc... Considering that concept, and joining it with multibird: Would be possible to create groups of sources and assigning different priorities to those groups on each instance of Bird. In this case, each Bird instance could run on a different box, or even on a different site. Further than that, on IXPs with a large number of participants, would be possible to define some affinity between that group of priority based for example on the facility where those participants are connected. I have a feeling that this would be especially useful for remote peering scenarios. Just a crazy idea to share with colleagues. Maybe from here, some good thing could rise. -- Douglas Fernando Fischer Engº de Controle e Automação
