On 7/1/2015 11:38 AM, Saumya Dikshit (sadikshi) wrote: > Hi Joe, > > Vxlan is a Layer-2 tunnel and carries layer-2 frame(complete packet > including l2 header) as payload.
If that is correct, then it has no business interacting with ICMP. It should be supporting the minimum required transit MTU for IPv4 or IPv6 (respectively), and where that's not directly possible it must support fragmentation and reassembly on its own. ... > Secondly, Vxlan Gateway can potentially act as a Layer-2 gateway and > Layer-3 gateway for client devices > connected over same or different subnet respectively. For Layer-2 gateway > case, MTU derivation may not > make sense, as the destination is one L3-hop away. IP hops are measured by the number of routers, not link. I.e., traversing one hop is one router, not one link. See RFC1812. Although I appreciate you're trying to optimize, ICMP PTBs are for "I can't carry this message at all", not "I wish it were smaller". If you try to interpret the PTBs incorrectly, you'll only create black holes. Further, the use of PMTUD is deprecated in favor of PLMTUD (RFC4821), precisely so the path properties to not rely on ICMPs - which are often blocked anyway. Again, these comments are NOT intended as issues to be "fixed" with document edits. Joe _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
