From mboxrd@z Thu Jan 1 00:00:00 1970 From: Murali Karicheri Subject: Re: Question on Bonding driver Date: Fri, 20 Feb 2015 11:59:44 -0500 Message-ID: <54E76800.4050604@ti.com> References: <54DE3056.6020606@ti.com> <4331.1423931133@nyx> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev , WingMan Kwok To: Jay Vosburgh Return-path: Received: from arroyo.ext.ti.com ([192.94.94.40]:48254 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754886AbbBTQ7q (ORCPT ); Fri, 20 Feb 2015 11:59:46 -0500 In-Reply-To: <4331.1423931133@nyx> Sender: netdev-owner@vger.kernel.org List-ID: On 02/14/2015 11:25 AM, Jay Vosburgh wrote: > Murali Karicheri wrote: > >> Hi, >> >> I am working to enable bonding driver on my hardware and trying to >> understand this. >> >> I am using the alb mode. I create a bond interface with 2 ethernet >> interfaces. First one is the basic question about net driver itself and >> second is about bonding. >> >> 1. Each ethernet interface has a MAC address. The hardware has MAC filter >> and the driver fills the net_device's dev_addr with its MAC address before >> calling register_netdev() API. When the net core calls ndo_start(), is the >> low level driver responsible for setting up its MAC address in the MAC >> filter of the hardware or low level driver will be told to do so by upper >> layer. Or is it required to set it up as part of ndo_set_rx_mode() or >> ndo_set_mac_address()? >> >> 2. In the case of bonding, the bond interface MAC address is copied from >> the active slave's MAC address. Also it updates the dev_addr in the netdev >> struct of each of the slave with its own MAC address. So I assume, the >> device/NIC now needs to accept packets to its original MAC address as well >> the bond's MAC address. This is especially more important for the slave's >> that are not active slave as it can be target of packets from Peers as >> part of rlb. So for the slave that is not active slave, MAC filter needs >> to include its original hw address as well unless the slave is put to >> promiscuous mode. So I am trying to figure out how this is expected to >> work? All slaves put to promiscuous mode or MAC filter updated by slave >> driver to include MAC addresses it is expected to filter on (bond MAC >> address and its own MAC address) > > I'm travelling at the moment, but the short answer for #2 is > that the way the alb mode works is basically that the non-active slaves > only receive for their own individual MAC. Peers within the L2 network > are "assigned" to those slaves via tailored ARPs sent to the specific > peers. The slaves do not generally go into promisc mode (there are > exceptions during failover type events), nor are they programmed with > multiple unicast MAC addreeses. > > I'd suggest you look at rlb_update_client in bond_alb.c and the > functions that call it to understand the logic. Thanks Jay. Will take a look. Murali > > -J > > --- > -Jay Vosburgh, jay.vosburgh@canonical.com > > -- Murali Karicheri Linux Kernel, Texas Instruments