Jun 14, 2017

Network Bonding on Ubuntu

Interface Configuration

Step 1: Ensure kernel support

You need to ensure that the correct kernel module bonding is present, and loaded at boot time.
Edit your /etc/modules configuration:
sudo vi /etc/modules
Ensure that the bonding module is loaded:
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.

bonding

Step 2: Configure network interfaces

Ensure that your network is brought down:
sudo service networking stop
Then load the bonding kernel module:
sudo modprobe bonding
Now you are ready to configure your NICs.
A general guideline is to:
  1. Pick which available NICs will be part of the bond.
  2. Configure all other NICs as usual
  3. Configure all bonded NICs:
    1. To be manually configured
    2. To join the named bond-master
  4. Configure the bond NIC as if it were a normal NIC
  5. Add bonding-specific parameters to the bond NIC as follows.
Edit your interfaces configuration:
 sudo vi /etc/network/interfaces
For example, to combine eth0 and eth1 as slaves to the bonding interface bond0 using a simple active-backup setup, with eth0 being the primary interface:
#source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback
#eno1 is manually configured, and slave to the "bond0" bonded NIC
auto eno1
iface eno1 inet manual
bond-master bond0
bond-primary eno1
#eno2 ditto, thus creating a 2-link bond.
auto eno2
iface eno2 inet manual
bond-master bond0
bond-primary eno2
# bond0 is the bonding NIC and can be used like any other normal NIC.
# bond0 is configured using static network information.
auto bond0
iface bond0 inet static
address 192.168.0.46
gateway 192.168.1.1
netmask 255.255.254.0
bond-mode active-backup
bond-miimon 100
bond-slaves none
dns-nameservers 8.8.8.8 8.8.4.4


The bond-primary directive, if needed, needs to be part of the slave description (eth0 in the example), instead of the master. Otherwise it will be ignored.
As another example, to combine eth0 and eth1 using the IEEE 802.3ad LACP bonding protocol:
#eth0 is manually configured, and slave to the "bond0" bonded NIC
auto eno1
iface eno1 inet manual
bond-master bond0

#eth1 ditto, thus creating a 2-link bond.
auto eno2
iface eno2 inet manual
bond-master bond0

# bond0 is the bonded NIC and can be used like any other normal NIC.
# bond0 is configured using static network information.
auto bond0
iface bond0 inet static
address 192.168.0.46
gateway 192.168.1.1
netmask 255.255.254.0
# bond0 uses standard IEEE 802.3ad LACP bonding protocol
bond-mode 4
bond-miimon 100
bond-lacp-rate 1
bond-slaves eno2 eno1 
dns-nameservers 8.8.8.8 8.8.4.4

For bonding-specific networking options please consult the documentation available at BondingModuleDocumentation.
Finally, bring up your network again:
sudo service networking start

Checking the bonding interface

Link information is available under /proc/net/bonding/. To check bond0 for example:
# cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: eno2 (primary_reselect always)
Currently Active Slave: eno2
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: eno1
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: b0:83:fe:d6:c5:33
Slave queue ID: 0

Slave Interface: eno2
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: b0:83:fe:d6:c5:34
Slave queue ID: 0

Bringing up/down bonding interface

To bring the bonding interface, run
ifup bond0
To bring down a bonding interface, run
ifdown bond0

Ethernet Bonding modes

Ethernet bonding has different modes you can use. You specify the mode for your bonding interface in /etc/network/interfaces. For example:
bond-mode active-backup

You need to disable network-manager service:

sudo systemctl stop network-manager
sudo systemctl disable network-manager