linux-toradex.git/Documentation/networking/bonding.txt, branch v3.12.8

bonding: Make alb learning packet interval configurable

2013-09-16T02:20:44+00:00

running bonding in ALB mode requires that learning packets be sent periodically,
so that the switch knows where to send responding traffic.  However, depending
on switch configuration, there may not be any need to send traffic at the
default rate of 3 packets per second, which represents little more than wasted
data.  Allow the ALB learning packet interval to be made configurable via sysfs

Signed-off-by: Neil Horman 
Acked-by: Acked-by: Veaceslav Falico 
CC: Jay Vosburgh 
CC: Andy Gospodarek 
CC: "David S. Miller" 
Signed-off-by: Andy Gospodarek 
Signed-off-by: David S. Miller

bonding: add an option to fail when any of arp_ip_target is inaccessible

2013-06-25T23:58:38+00:00

Currently, we fail only when all of the ips in arp_ip_target are gone.
However, in some situations we might need to fail if even one host from
arp_ip_target becomes unavailable.

All situations, obviously, rely on the idea that we need *completely*
functional network, with all interfaces/addresses working correctly.

One real world example might be:
vlans on top on bond (hybrid port). If bond and vlans have ips assigned
and we have their peers monitored via arp_ip_target - in case of switch
misconfiguration (trunk/access port), slave driver malfunction or
tagged/untagged traffic dropped on the way - we will be able to switch
to another slave.

Though any other configuration needs that if we need to have access to all
arp_ip_targets.

This patch adds this possibility by adding a new parameter -
arp_all_targets (both as a module parameter and as a sysfs knob). It can be
set to:

	0 or any (the default) - which works exactly as it's working now -
	the slave is up if any of the arp_ip_targets are up.

	1 or all - the slave is up if all of the arp_ip_targets are up.

This parameter can be changed on the fly (via sysfs), and requires the mode
to be active-backup and arp_validate to be enabled (it obeys the
arp_validate config on which slaves to validate).

Internally it's done through:

1) Add target_last_arp_rx[BOND_MAX_ARP_TARGETS] array to slave struct. It's
   an array of jiffies, meaning that slave->target_last_arp_rx[i] is the
   last time we've received arp from bond->params.arp_targets[i] on this
   slave.

2) If we successfully validate an arp from bond->params.arp_targets[i] in
   bond_validate_arp() - update the slave->target_last_arp_rx[i] with the
   current jiffies value.

3) When getting slave's last_rx via slave_last_rx(), we return the oldest
   time when we've received an arp from any address in
   bond->params.arp_targets[].

If the value of arp_all_targets == 0 - we still work the same way as
before.

Also, update the documentation to reflect the new parameter.

v3->v4:
Kill the forgotten rtnl_unlock(), rephrase the documentation part to be
more clear, don't fail setting arp_all_targets if arp_validate is not set -
it has no effect anyway but can be easier to set up. Also, print a warning
if the last arp_ip_target is removed while the arp_interval is on, but not
the arp_validate.

v2->v3:
Use _bh spinlock, remove useless rtnl_lock() and use jiffies for new
arp_ip_target last arp, instead of slave_last_rx(). On bond_enslave(),
use the same initialization value for target_last_arp_rx[] as is used
for the default last_arp_rx, to avoid useless interface flaps.

Also, instead of failing to remove the last arp_ip_target just print a
warning - otherwise it might break existing scripts.

v1->v2:
Correctly handle adding/removing hosts in arp_ip_target - we need to
shift/initialize all slave's target_last_arp_rx. Also, don't fail module
loading on arp_all_targets misconfiguration, just disable it, and some
minor style fixes.

Signed-off-by: Veaceslav Falico 
Signed-off-by: David S. Miller

bonding: doc: some details on backup slave arp validation

2013-06-25T23:58:38+00:00

Add some details to bonding documentation on how backup slave arp
validation works.

Signed-off-by: Veaceslav Falico 
Signed-off-by: David S. Miller

bonding: remove ifenslave.c from kernel source

2013-05-28T06:34:46+00:00

As Stephen proposed:
Since bonding supports configuration via iproute (netlink) and sysfs, I think
it is time to purge the old ifenslave code out of Documentation/networking
and update the documentation.

Suggested-by: Stephen Hemminger 
Cc: Stephen Hemminger 
Cc: Jay Vosburgh 
Cc: "David S. Miller" 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller

bonding: support for IPv6 transmit hashing

2012-08-23T05:49:30+00:00

Currently the "bonding" driver does not support load balancing outgoing
traffic in LACP mode for IPv6 traffic. IPv4 (and TCP or UDP over IPv4)
are currently supported; this patch adds transmit hashing for IPv6 (and
TCP or UDP over IPv6), bringing IPv6 up to par with IPv4 support in the
bonding driver. In addition, bounds checking has been added to all
transmit hashing functions.

The algorithm chosen (xor'ing the bottom three quads of the source and
destination addresses together, then xor'ing each byte of that result into
the bottom byte, finally xor'ing with the last bytes of the MAC addresses)
was selected after testing almost 400,000 unique IPv6 addresses harvested
from server logs. This algorithm had the most even distribution for both
big- and little-endian architectures while still using few instructions. Its
behavior also attempts to closely match that of the IPv4 algorithm.

The IPv6 flow label was intentionally not included in the hash as it appears
to be unset in the vast majority of IPv6 traffic sampled, and the current
algorithm not using the flow label already offers a very even distribution.

Fragmented IPv6 packets are handled the same way as fragmented IPv4 packets,
ie, they are not balanced based on layer 4 information. Additionally,
IPv6 packets with intermediate headers are not balanced based on layer
4 information. In practice these intermediate headers are not common and
this should not cause any problems, and the alternative (a packet-parsing
loop and look-up table) seemed slow and complicated for little gain.

Tested-by: John Eaglesham 
Signed-off-by: John Eaglesham 
Signed-off-by: David S. Miller

net-next: minor cleanups for bonding documentation

2012-07-22T19:44:01+00:00

The section titled "Configuring Bonding for Maximum Throughput" is
actually section twelve not thirteen, and there are a couple of words
spelled incorrectly.

Signed-off-by: Rick Jones 
Reviewed-by: Nicolas de Pesloüan 
Signed-off-by: Jay Vosburgh 
Signed-off-by: David S. Miller

Documentation: replace install commands with softdeps

2012-03-30T23:03:15+00:00

Install commands should not be used to specify soft dependencies among
modules. When loading modules it's much better to have a softdep that
modprobe knows what's being done than having to fork/exec another
instance of modprobe to load the other module.

By using a softdep user has also an option to remove the dependencies
when removing the module (and if its refcount dropped to 0)

Signed-off-by: Lucas De Marchi 
Signed-off-by: Linus Torvalds

Documentation: remove references to /etc/modprobe.conf

2012-03-30T23:03:15+00:00

Usage of /etc/modprobe.conf file was deprecated by module-init-tools and
is no longer parsed by new kmod tool. References to this file are
replaced in Documentation, comments and Kconfig according to the
context.

There are also some references to the old /etc/modules.conf from 2.4
kernels that are being removed.

Signed-off-by: Lucas De Marchi 
Acked-by: Takashi Iwai 
Acked-by: Mauro Carvalho Chehab 
Signed-off-by: Randy Dunlap 
Signed-off-by: Linus Torvalds

bonding: document undocumented active_slave sysfs entry.

2011-12-27T01:09:35+00:00

v2, based on Jay's review.

I kept the 'link must be up' part, because this is enforced in the code.

Signed-off-by: Nicolas de Pesloüan 
Signed-off-by: Jay Vosburgh 
cc: Andy Gospodarek 
Signed-off-by: David S. Miller

bonding: document two undocumented options.

2011-08-08T05:16:22+00:00

Commit 655f8919d549ad1872e24d826b6ce42530516d2e
    bonding: add min links parameter to 802.3ad

and commit ebd8e4977a87cb81d93c62a9bff0102a9713722f
    bonding: add all_slaves_active parameter

introduced new options to bonding, but didn't provide the documentation
for those options.

V2: add the default value for both options.
V3: document the exact behavior of min_links default value.

Signed-off-by: Nicolas de Pesloüan 
Signed-off-by: David S. Miller