Bonding is a feature that can be enabled bu the Linux kernel, to allow system administrators to combine two or more network interface to form a single, logical “bonded” interface, for redundancy or increased throughput purpose.
We can configure Linux bonding in 7 different modes. The behavior of the bonded interfaces depends upon the mode.
Below are the available bonding modes.
[highlight1]1-Balance-round robin (mode 0)
2-Active-backup (mode 1)
3-Balance-xor (mode 2)
4-Broadcast (mode 3)
5-802.3ad (mode 4)
6-Balance-tlb (mode 5)
7-Balance-alb (mode 6)
Configuring a bonding Channel between eth0 and eth1 using the default mode i.e. Mode-0 (balance-rr)
1. Network manager should not be running on the system, as NIM doesn’t support bonding. So please stop and disable the networkmanager service.
[highlight1] # service NetworkManager stop
# chkconfig NetworkManager off
2. Bonding module should be configured and loaded. To enable bonding module, create a bonding.conf file as below.
Note : you can add multiple entries to create multiple bonding channels like bond0, bond1, bond2…etc
# cat > /etc/modprobe.d/bonding.conf
alias bond0 bonding
options bond0 mode=1 miimon=100
3. Create a configuration file for the bonding channel i.e. bond0, as below
# cat /etc/sysconfig/network-scripts/ifcfg-bond0
4. Create configuration files for all the interfaces i.e. eth0 and eth1, which are participating in the bonding channel
# cat > /etc/sysconfig/network-scripts/ifcfg-eth0
# cat > /etc/sysconfig/network-scripts/ifcfg-eth1
5. Activating Bonding Channel
[highlight1]a. With out rebooting
# modprobe bonding
# service network restart
b. with reboot
6. Verify that Bonding channel is active, by using the commands
# cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.0.2 (Nov 25, 2012)
[highlight1] Bonding Mode: adaptive load balancing
Primary Slave: None
Currently Active Slave: eth0
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0
[highlight1]Slave Interface: eth0
MII Status: up
Link Failure Count: 0
Permanent HW addr: aa:bb:cc:dd:ee:ff
[highlight2]Best Info From Zenlab – Important[/highlight2]
[no_overflow]Configurable Bonding Parameters: –[/no_overflow]
max_bonds : specifies the number of bonding devices that can be configured on single bonding driver.
xmit_hash_policy : Slecect the transmit has policy to use for slave selection in balance-xor and 802.3d modevice. Possible values , layer2 (default) , larer2+3 or layer3+4
arp_interval : Specifies the ARP link monitoring frequency in milli seconds
arp_ip_target : Specifies the IP addresses to use as ARP monitoring peers when arp_interval is > 0. Multiple IP addresses must be seperated by comma. At least one IP addres must be given for ARP monitoring to work. Max. no. of target IPs are 16.
arp_validate : Specifies Whether or not ARP probes and replies should be validated in the active-backup mode. This causes the ARP monitor to examine the incoming ARP requests and replies, and only consider a slave to be up if it is receiving the appropriate ARP traffic. Possible values
[highlight1]none(0) – default value
active(1) – validate only the active slave
backup(2) – validate only the backup slave
all(3) – validate all slaves[/highlight1]
miimon : Specifies the MII link monitoring frequency in milliseconds. A value of 0 disables the MII link monitroing. A value of 100 is recommended.
updelay : specifies the time, in milliseconds, to wait before disabling a slave after a link recovery has been detected.
downdelay : specifies the time, in milliseconds, to wait before disabling a slava after a link failure has been detected.
use_carrier : specifies whether or not miimon shoudl use MII/ETHTOO “ioctls for value of 0 ” or ” netif_carrier_ok() for value 1 ( default value)” functions to determine the link status.