[openib-general] question regarding GRH flag in ib_ah_attr

[Roland Dreier]

    Sean> We currently use ARP to resolve an IP address to a DGID,
    Sean> which I don't believe will work across a router.  Does an
    Sean> app even know enough to be able to get a path record?

I think you're fine.  The IB router just has to handle forwarding
multicasts between two IB subnets for ARP to work.

If there's also an IP router in between the two hosts then there's a
problem, but I don't think it's that reasonable to expect to make a
direct RDMA connection in that case.

 - R.