Skip to main content Logo (IEC resistor symbol)logo

Quis custodiet ipsos custodes?
Home | About | All pages | RSS Feed | Gopher

Bonding NIC Teaming on Ubuntu 12.04

Published: 14-02-2014 | Author: Remy van Elst | Text only version of this article

Table of Contents

Bonding, also called port trunking or link aggregation means combining severalnetwork interfaces (NICs) to a single link, providing either high-availability,load-balancing, maximum throughput, or a combination of these.

If you like this article, consider sponsoring me by trying out a Digital OceanVPS. With this link you'll get $100 credit for 60 days). (referral link)

Warning! Make sure you have ILO/BMC out of band remote access to your server.You are going to change vital network settings, this may result in loss ofconnectivity if done wrong.

Install required packages

ifenslave is used to attach and detach slave network interfaces to a bondingdevice. Install the package:

apt-get install ifenslave

Kernel Module

Before Ubuntu can configure your network cards into a NIC bond, you need toensure that the correct kernel module bonding is present, and loaded at boottime.

Edit the file:

vim  /etc/modules

Add the word bonding to the file:


Also, load the module manually for now:

modprobe bonding

Bonding network config

Edit the file:

vim /etc/network/interfaces

Example config for an round-robin load balancing setup:

auto loiface lo inet loopbackauto eth0iface eth0 inet manual    bond-master bond0auto eth1iface eth1 inet manual    bond-master bond0auto bond0iface bond0 inet static    # For jumbo frames, change mtu to 9000    mtu 1500    address    netmask    network    broadcast    gateway    dns-nameservers    bond-miimon 100 # Specifies the MII link monitoring frequency in milliseconds. This determines how often the link state of each slave is inspected for link failures.     bond-downdelay 200 # Specifies the time, in milliseconds, to wait before disabling a slave after a link failure has been detected.    bond-updelay 200 # Specifies the time, in milliseconds, to wait before enabling a slave after a link recovery has been detected.    bond-mode 0    bond-slaves none # we already defined the interfaces above with bond-master

For round-robin/load balancing, use bond-mode: balance-rr.

Bonding modes explained

Mode 0 - balance-rr

Round-robin policy: Transmit packets in sequential order from the firstavailable slave through the last. This mode provides load balancing and faulttolerance.

Mode 1 - active-backup

Active-backup policy: Only one slave in the bond is active. A different slavebecomes active if, and only if, the active slave fails. The bond's MAC addressis externally visible on only one port (network adapter) to avoid confusing theswitch. This mode provides fault tolerance. The primary option affects thebehavior of this mode.

Mode 2 - balance-xor

XOR policy: Transmit based on [(source MAC address XOR'd with destination MACaddress) modulo slave count]. This selects the same slave for each destinationMAC address. This mode provides load balancing and fault tolerance.

Mode 3 - broadcast

Broadcast policy: transmits everything on all slave interfaces. This modeprovides fault tolerance.

Mode 4 - 802.3ad

IEEE 802.3ad Dynamic link aggregation. Creates aggregation groups that share thesame speed and duplex settings. Utilizes all slaves in the active aggregatoraccording to the 802.3ad specification.


Mode 5 - balance-tlb

Adaptive transmit load balancing: channel bonding that does not require anyspecial switch support. The outgoing traffic is distributed according to thecurrent load (computed relative to the speed) on each slave. Incoming traffic isreceived by the current slave. If the receiving slave fails, another slave takesover the MAC address of the failed receiving slave.


Mode 6 - balance-alb

Adaptive load balancing: includes balance-tlb plus receive load balancing (rlb)for IPV4 traffic, and does not require any special switch support. The receiveload balancing is achieved by ARP negotiation. The bonding driver intercepts theARP Replies sent by the local system on their way out and overwrites the sourcehardware address with the unique hardware address of one of the slaves in thebond such that different peers use different hardware addresses for the server.


Tags: bonding, failover, network, teaming, tutorials, ubuntu