• David Hancock's avatar
    Document fix for return-to-sender behavior for non-head vdevs · 879195b9
    David Hancock authored
    The issue is that some vdevs, like the arp proxy, want to
    send traffic back out the same port that received it in some
    cases, but the ingress port has been handled in such a way
    that vdevs not at the head of the chain lose the information
    about the original physical ingress port.  There are two
    ways to fix this - change the controller (primarily in the
    Lease class), or change HP4.  Changing HP4 looks a lot easier,
    and though composition abstraction flexibility is no longer
    as straightforward, it is still there.  Specifically, a vdev
    in a virtual network wanting to return traffic back to another
    vdev will have to do so via explicit forwarding instead of
    simply copying ingress_port to egress_spec.  The compiler can
    be modified to accommodate this change without requiring the
    user to be aware of it.