From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Frederic Sowa Subject: Re: [PATCH v2 net-next] ipv6: router reachability probing Date: Wed, 11 Dec 2013 20:10:23 +0100 Message-ID: <20131211191023.GA4675@order.stressinduktion.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: netdev@vger.kernel.org, Hideaki YOSHIFUJI To: Jiri Benc Return-path: Received: from order.stressinduktion.org ([87.106.68.36]:48901 "EHLO order.stressinduktion.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751084Ab3LKTKY (ORCPT ); Wed, 11 Dec 2013 14:10:24 -0500 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Dec 11, 2013 at 01:48:20PM +0100, Jiri Benc wrote: > RFC 4191 states in 3.5: > > When a host avoids using any non-reachable router X and instead sends > a data packet to another router Y, and the host would have used > router X if router X were reachable, then the host SHOULD probe each > such router X's reachability by sending a single Neighbor > Solicitation to that router's address. A host MUST NOT probe a > router's reachability in the absence of useful traffic that the host > would have sent to the router if it were reachable. In any case, > these probes MUST be rate-limited to no more than one per minute per > router. > > Currently, when the neighbour corresponding to a router falls into > NUD_FAILED, it's never considered again. Introduce a new rt6_nud_state > value, RT6_NUD_FAIL_PROBE, which suggests the route should not be used but > should be probed with a single NS. The probe is ratelimited by the existing > code. To better distinguish meanings of the failure values, rename > RT6_NUD_FAIL_SOFT to RT6_NUD_FAIL_DO_RR. > > Signed-off-by: Jiri Benc Acked-by: Hannes Frederic Sowa Looks good, thanks!