summaryrefslogtreecommitdiffstats
path: root/Documentation/networking
diff options
context:
space:
mode:
authorJay Vosburgh <fubar@us.ibm.com>2007-12-06 23:40:34 -0800
committerJeff Garzik <jeff@garzik.org>2007-12-07 15:00:32 -0500
commit6f6652be183c8c7cb99c646dd7494ab45e4833ba (patch)
tree8ab3acaa0f7887aad46d0a1dd10f800312d657fa /Documentation/networking
parentb63bb739a1d24f395c09f88ff43c54c736a60453 (diff)
downloadlinux-6f6652be183c8c7cb99c646dd7494ab45e4833ba.tar.bz2
bonding: Add new layer2+3 hash for xor/802.3ad modes
Add new hash for balance-xor and 802.3ad modes. Originally submitted by "Glenn Griffin" <ggriffin.kernel@gmail.com>; modified by Jay Vosburgh to move setting of hash policy out of line, tweak the documentation update and add version update to 3.2.2. Glenn's original comment follows: Included is a patch for a new xmit_hash_policy for the bonding driver that selects slaves based on MAC and IP information. This is a middle ground between what currently exists in the layer2 only policy and the layer3+4 policy. This policy strives to be fully 802.3ad compliant by transmitting every packet of any particular flow over the same link. As documented the layer3+4 policy is not fully compliant for extreme cases such as ip fragmentation, so this policy is a nice compromise for environments that require full compliance but desire more than the layer2 only policy. Signed-off-by: "Glenn Griffin" <ggriffin.kernel@gmail.com> Signed-off-by: Jay Vosburgh <fubar@us.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'Documentation/networking')
-rw-r--r--Documentation/networking/bonding.txt29
1 files changed, 27 insertions, 2 deletions
diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt
index 11340625e363..6cc30e0d5795 100644
--- a/Documentation/networking/bonding.txt
+++ b/Documentation/networking/bonding.txt
@@ -554,6 +554,30 @@ xmit_hash_policy
This algorithm is 802.3ad compliant.
+ layer2+3
+
+ This policy uses a combination of layer2 and layer3
+ protocol information to generate the hash.
+
+ Uses XOR of hardware MAC addresses and IP addresses to
+ generate the hash. The formula is
+
+ (((source IP XOR dest IP) AND 0xffff) XOR
+ ( source MAC XOR destination MAC ))
+ 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
+ hash policy.
+
+ This policy is intended to provide a more balanced
+ distribution of traffic than layer2 alone, especially
+ in environments where a layer3 gateway device is
+ required to reach most destinations.
+
+ This algorithm is 802.3ad complient.
+
layer3+4
This policy uses upper layer protocol information,
@@ -589,8 +613,9 @@ xmit_hash_policy
or may not tolerate this noncompliance.
The default value is layer2. This option was added in bonding
-version 2.6.3. In earlier versions of bonding, this parameter does
-not exist, and the layer2 policy is the only policy.
+ version 2.6.3. In earlier versions of bonding, this parameter
+ does not exist, and the layer2 policy is the only policy. The
+ layer2+3 value was added for bonding version 3.2.2.
3. Configuring Bonding Devices