> > If switches were to try to distribute GRE flows between two VTEPs > > that used a GRE encapsulation, all the traffic would be directed to > > use only one link within these Port Channels. > > Not true. GRE encapsulation is not mandated to use the same src/dst > addresses for all flows between given two end points.
True, but then you need a mechanism to discover all the available endpoints, whereas with single VTEP per host you can use existing mechanisms (either learning from source IP address or next-hop distribution with BGP-like protocols). > You do not need to parse deep into packet to enable good load balancing > hash across parallel links when you use GRE as an encapsulation > technology. True, but many existing DC switches that do IP-based load balancing have no problems load-balancing on UDP 5-tuple. I am positive there's equipment out there that can do load balancing on GRE keys (or some other part of GRE header), I just haven't encountered it yet (or realized it does that), so please fix my ignorance. > And what is nice about IP encapsulation all GRE src/dst addresses can be > naturally aggregated so from IGP point of view they still look like a > single prefix. ... and you need a new endpoint prefix (or set-of-addresses) discovery mechanism. Ivan _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
