Introduction

Ethernet bonding provides a backup or alternative Ethernet connection in case the primary physical connection fails. It creates more than one path on the same network. Your device must have an Ethernet port in one of the accessory ports in order to do bonding.

To setup bonding:

1. Check if you have the bonding driver, and its version:

mtcdt: modinfo bonding
filename:       /lib/modules/3.12.27r13/kernel/drivers/net/bonding/bonding.ko
alias:          rtnl-link-bond
author:         Thomas Davis, tadavis@lbl.gov and many others
description:    Ethernet Channel Bonding Driver, v3.7.1
version:        3.7.1
...

2. If the bonding module is not present, build it: bonding.ko. You should substitute your ethernet devices for eth1 and eth2. For instance, you may wish to use eth0 and eth1. For bonding,you don’t need identical interfaces.

Here is an example of how to configure the bond.  Place it in /etc/network/interfaces:

auto bond0
iface bond0 inet static
address 10.0.0.130
netmask 255.0.0.0
bond-mode active-backup
bond-miimon 100
bond-slaves eth1 eth2
# The following sets bonding debug in the setup
# verbosity 1

Bring up the bond

To bring up the bond, enter the command:

mtcdt: ifup bond0

Checking the status of the bond

To display the status of the bond, enter the command:

mtcdt: cat /proc/net/bonding/bond0

The following results display:

Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: None
Currently Active Slave: eth1
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: eth1
MII Status: up
Speed: 100 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 00:08:00:4a:00:09
Slave queue ID: 0

Slave Interface: eth2
MII Status: up
Speed: 100 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 00:08:00:82:00:a0
Slave queue ID: 0