From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: bonding xmit_policy
Date: Tue, 15 Nov 2011 08:12:15 +0100
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To: Simon Chen <simonchennj@gmail.com>
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Le mardi 15 novembre 2011 =C3=A0 01:20 -0500, Simon Chen a =C3=A9crit :
> Thanks, my bad.
>=20
> It is pretty strange that when I use 802.3ad mode, all my packets
> (from different TCP flows) egress the same NIC even though I choose
> xmit_policy to be layer3+4. That's why I wasn't quite sure whether th=
e
> policy is indeed in place.
>=20
> When I switch to balance-xor mode, the packets are roughly evenly
> distributed across two NICs.

AFAIK, layer4 information (soure/dst ports) is limited to ipv4 TCP/UDP
trafic.

Moreover, if your bond has 2 ports, only low order bit of source and ds=
t
port is used.

layer4_xor =3D ntohs((*layer4hdr ^ *(layer4hdr + 1)));

So if your trafic is RTP, it probably use only even ports, (RTCP using
odd ports), and uses a single slave.

=20