Using Multiple Ethernet Cards; The Channel Bonding Module - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

Chapter 41. General Parameters and Modules
Hardware
3043 Rhine-I D-Link DFE-930-
TX PCI 10/100
Table 41.2. Ethernet Module Parameters

41.5.1. Using Multiple Ethernet Cards

It is possible to use multiple Ethernet cards on a single machine. For each card there must be an
alias and, possibly, options lines for each card in /etc/modprobe.conf.
For additional information about using multiple Ethernet cards, refer to the Linux Ethernet-HOWTO
online at http://www.redhat.com/mirrors/LDP/HOWTO/Ethernet-HOWTO.html.

41.5.2. The Channel Bonding Module

Red Hat Enterprise Linux allows administrators to bind NICs together into a single channel using
the bonding kernel module and a special network interface, called a channel bonding interface.
Channel bonding enables two or more network interfaces to act as one, simultaneously increasing the
bandwidth and providing redundancy.
To channel bond multiple network interfaces, the administrator must perform the following steps:
1. Add the following line to /etc/modprobe.conf:
alias bond<N> bonding
Replace <N> with the interface number, such as 0. For each configured channel bonding
interface, there must be a corresponding entry in /etc/modprobe.conf.
2. Configure a channel bonding interface as outlined in
3. To enhance performance, adjust available module options to ascertain what combination works
best. Pay particular attention to the miimon or arp_interval and the arp_ip_target
parameters. Refer to
and how to quickly determine the best ones for your bonded interface.
41.5.2.1. bonding Module Directives
It is a good idea to test which channel bonding module parameters work best for your bonded
interfaces before adding them to the BONDING_OPTS="<bonding parameters>" directive in your
bonding interface configuration file (ifcfg-bond0 for example). Parameters to bonded interfaces
can be configured without unloading (and reloading) the bonding module by manipulating files in the
sysfs file system.
574
Module
Section 41.5.2.1, "bonding Module Directives"
Parameters
debug — VIA Rhine debug
level (0-7)
rx_copybreak — VIA Rhine
copy breakpoint for copy-only-
tiny-frames
avoid_D3 — Avoid power
state D3 (work-around for
broken BIOSes)
Section 14.2.3, "Channel Bonding
for a list of available options
Interfaces".