From mboxrd@z Thu Jan 1 00:00:00 1970 From: Veaceslav Falico Subject: [PATCH net-next] bonding: send arp requests even if there's no route to them Date: Fri, 28 Feb 2014 11:57:56 +0100 Message-ID: <1393585076-22786-1-git-send-email-vfalico@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Veaceslav Falico , =?UTF-8?q?Fran=C3=A7ois=20CACHEREUL?= , Zhenjie Chen , Jay Vosburgh , Andy Gospodarek To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:18434 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751157AbaB1LCN (ORCPT ); Fri, 28 Feb 2014 06:02:13 -0500 Sender: netdev-owner@vger.kernel.org List-ID: Currently we're only sending arp requests if we have a route to the tar= get (and, thus, can find out the source ip address). There are some use cases, however, where we don't want/need to set an i= p address (or set up a specific route) for bonding to use arp monitoring = *for traffic generation*. We can easily send arp probes (arp requests with s= rc ip =3D=3D 0) to generate arp broadcast responses from the target ip and= use them for determining if the target is up. This, obviously, won't work with arp validation - because we don't have= the ip address set and, thus, will filter out the responses. So in that cas= e - print a warning. CC: Fran=C3=A7ois CACHEREUL CC: Zhenjie Chen CC: Jay Vosburgh CC: Andy Gospodarek Signed-off-by: Veaceslav Falico --- drivers/net/bonding/bond_main.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond= _main.c index 12948b3..a217536 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -2155,8 +2155,13 @@ static void bond_arp_send_all(struct bonding *bo= nd, struct slave *slave) rt =3D ip_route_output(dev_net(bond->dev), targets[i], 0, RTO_ONLINK, 0); if (IS_ERR(rt)) { - pr_debug("%s: no route to arp_ip_target %pI4\n", - bond->dev->name, &targets[i]); + /* there's no route to target - try to send arp + * probe to generate any traffic (arp_validate=3D0) + */ + if (bond->params.arp_validate) + pr_warn("%s: no route to arp_ip_target %pI4 and arp_validate is se= t\n", + bond->dev->name, &targets[i]); + bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i], 0, 0); continue; } =20 --=20 1.8.4