From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: igmp: Staggered igmp report intervals for unsolicited igmp reports Date: Thu, 23 Sep 2010 11:26:03 -0600 Message-ID: <20100923172603.GM11157@obsidianresearch.com> References: <20100922215052.GK11157@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Stevens , linux-rdma@vger.kernel.org, netdev@vger.kernel.org, Bob Arendt To: Christoph Lameter Return-path: Received: from quartz.orcorp.ca ([139.142.54.143]:56080 "EHLO quartz.orcorp.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755427Ab0IWR0N (ORCPT ); Thu, 23 Sep 2010 13:26:13 -0400 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Sep 23, 2010 at 10:32:17AM -0500, Christoph Lameter wrote: > > Is the issue you are dropping IGMP packets because the 224.0.0.2 join > > hasn't finished? Ideally you'd wait for the SA to reply before sending > > a IGMP, but a simpler solution might just be to use the broadcast MLID > > for packets addressed to a MGID that has not yet got a MLID. This > > would bebe similar to the ethernet behaviour of flooding. > > IGMP reports are sent on the multicast group not on 224.0.0.2. 224.0.0.2 > is only used when leaving a multicast group. Hm, that is quite different than in IGMPv3.. How does this work at all in IB? A message to the multicast group isn't going to make it to any routers unless the routers use some other means to join the IB MGID. Jason