From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roland Dreier Subject: Re: Advice needed on IP-over-InfiniBand driver Date: Sun, 19 Sep 2004 21:51:49 -0700 Sender: netdev-bounce@oss.sgi.com Message-ID: <52u0ttr196.fsf@topspin.com> References: <52fz5esxx6.fsf@topspin.com> <20040919140133.60ea3fb3.davem@davemloft.net> <1095628759.1049.22.camel@jzny.localdomain> <20040919193415.6dc96cab.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: hadi@cyberus.ca, netdev@oss.sgi.com Return-path: To: "David S. Miller" In-Reply-To: <20040919193415.6dc96cab.davem@davemloft.net> (David S. Miller's message of "Sun, 19 Sep 2004 19:34:15 -0700") Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org David> It sounds like a two-stage thing, the first stage lets you David> talk on the subnet and get to the IB subnet manager, and David> the second stage lets you acually speak IP. My David> understanding, from his description, is that once the David> second stage part is complete you don't need to first stage David> address information at all. Pretty much... ARP gives you a unique identifier for the port with the IP address you're looking for. Then you need to take that unique identifier and ask the subnet manager what path to use to get from your local port to that destination port. (Talking to the subnet manager uses an InfiniBand native, non-IP mechanism -- one of the first things the subnet manager does is go over the whole fabric and tell each port what path to use to send it queries) Thanks, Roland