From mboxrd@z Thu Jan 1 00:00:00 1970 From: YOSHIFUJI Hideaki Subject: Re: [PATCH V2 0/1] neighbour: Support broadcast ARP in neighbor PROPE state Date: Thu, 12 Mar 2015 17:42:53 +0900 Message-ID: <5501518D.2070405@miraclelinux.com> References: <1426143501-30827-1-git-send-email-Yanjun.Zhu@windriver.com> <55013BD4.2080605@windriver.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: hideaki.yoshifuji@miraclelinux.com, "YOSHIFUJI Hideaki (USAGI Project)" To: yzhu1 , brian.haley@hp.com, davem@davemloft.net, alexandre.dietsch@windriver.com, clinton.slabbert@windriver.com, kuznet@ms2.inr.ac.ru, jmorris@namei.org, kaber@trash.net, netdev@vger.kernel.org, ulf.samuelsson@ericsson.com Return-path: Received: from exprod7og124.obsmtp.com ([64.18.2.26]:45196 "HELO exprod7og124.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753057AbbCLIm7 (ORCPT ); Thu, 12 Mar 2015 04:42:59 -0400 Received: by mail-pd0-f181.google.com with SMTP id fp1so18427984pdb.2 for ; Thu, 12 Mar 2015 01:42:58 -0700 (PDT) In-Reply-To: <55013BD4.2080605@windriver.com> Sender: netdev-owner@vger.kernel.org List-ID: Hello. yzhu1 wrote: > The state machine is in the attachment. > > Best Regards! > Zhu Yanjun > On 03/12/2015 02:58 PM, Zhu Yanjun wrote: >> V2: >> set ARP_PROBE_BCAST default N. >> >> V1: >> Have a problem with an HP router at a certain location, which >> is configured to only answer to broadcast ARP requests. >> That cannot be changed. >> >> The first ARP request the kernel sends out, is a broadcast request, >> which is fine, but after the reply, the kernel sends unicast requests, >> which will not get any replies. >> >> The ARP entry will after some time enter STALE state, >> and if nothing is done it will time out, and be removed. >> This process takes to long, and I have been told that it is >> difficult to makes changes that will eventually remove it. >> >> Have tried to change the state from STALE to INCOMPLETE, which failed, >> and then tried to change the state to PROBE which also failed. >> >> The stack is only sending out unicasts, and never broadcast. >> Is there any way to get the stack to send out a broadcast ARP >> without having to wait for the entry to be removed? Neighbour subsystem will send multicast probes after unicast probes in NUD_PROBE state if mcast_solicit is more than ucast_solicit. Try setting net.ipv4.neigh.*.ucast_solicit to the value less than net.ipv4.neigh.*.mcast_solicit, please? e.g. net.ipv4.neigh.eth0.mcast_solicit = 3 net.ipv4.neigh.eth0.ucast_solicit = 1 --yoshfuji >> >> I think the recommended behaviour in IPv6 is to send out 3 unicasts >> and if all fails, to send out broadcasts. >> >> Zhu Yanjun (1): >> neighbour: Support broadcast ARP in neighbor PROPE state >> >> include/net/neighbour.h | 7 ++++++ >> include/uapi/linux/neighbour.h | 6 +++++ >> include/uapi/linux/sysctl.h | 3 +++ >> kernel/sysctl_binary.c | 3 +++ >> net/core/neighbour.c | 44 +++++++++++++++++++++++++++++--- >> net/ipv4/Kconfig | 57 ++++++++++++++++++++++++++++++++++++++++++ >> net/ipv4/arp.c | 7 ++++-- >> 7 files changed, 121 insertions(+), 6 deletions(-) >> > -- Hideaki Yoshifuji Technical Division, MIRACLE LINUX CORPORATION