From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Eaglesham Subject: [PATCH v4 2/2] Update bonding driver documentation to include IPv6 transmit hashing algorithm. Date: Sun, 1 Jul 2012 00:01:39 -0700 Message-ID: References: Cc: John Eaglesham To: netdev@vger.kernel.org Return-path: Received: from smtp171.dfw.emailsrvr.com ([67.192.241.171]:45260 "EHLO smtp171.dfw.emailsrvr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751835Ab2GAHCn (ORCPT ); Sun, 1 Jul 2012 03:02:43 -0400 In-Reply-To: In-Reply-To: References: Sender: netdev-owner@vger.kernel.org List-ID: --- Documentation/networking/bonding.txt | 31 ++++++++++++++++++++++++++----- 1 file changed, 26 insertions(+), 5 deletions(-) diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index bfea8a3..5db14fe 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt @@ -752,12 +752,22 @@ xmit_hash_policy protocol information to generate the hash. Uses XOR of hardware MAC addresses and IP addresses to - generate the hash. The formula is + generate the hash. The IPv4 formula is (((source IP XOR dest IP) AND 0xffff) XOR ( source MAC XOR destination MAC )) modulo slave count + The IPv6 forumla is + + iphash = + (source ip quad 2 XOR dest IP quad 2) XOR + (source ip quad 3 XOR dest IP quad 3) XOR + (source ip quad 4 XOR dest IP quad 4) + + ((iphash >> 16) XOR (iphash >> 8) XOR iphash) + modulo slave count + This algorithm will place all traffic to a particular network peer on the same slave. For non-IP traffic, the formula is the same as for the layer2 transmit @@ -778,19 +788,30 @@ xmit_hash_policy slaves, although a single connection will not span multiple slaves. - The formula for unfragmented TCP and UDP packets is + The formula for unfragmented IPv4 TCP and UDP packets is ((source port XOR dest port) XOR ((source IP XOR dest IP) AND 0xffff) modulo slave count - For fragmented TCP or UDP packets and all other IP - protocol traffic, the source and destination port + The formula for unfragmented IPv6 TCP and UDP packets is + + iphash = + (source ip quad 2 XOR dest IP quad 2) XOR + (source ip quad 3 XOR dest IP quad 3) XOR + (source ip quad 4 XOR dest IP quad 4) + + ((source port XOR dest port) XOR + (iphash >> 16) XOR (iphash >> 8) XOR iphash) + modulo slave count + + For fragmented TCP or UDP packets and all other IPv4 and + IPv6 protocol traffic, the source and destination port information is omitted. For non-IP traffic, the formula is the same as for the layer2 transmit hash policy. - This policy is intended to mimic the behavior of + The IPv4 policy is intended to mimic the behavior of certain switches, notably Cisco switches with PFC2 as well as some Foundry and IBM products. -- 1.7.11