How to configure bonding

[root@openstack ~]# modprobe bonding

To list the bonding module info, use following command.

[root@openstack ~]# modinfo bonding

Step:1 Create Bond Interface File

Create a bond interface file (ifcfg-bond0) under the folder “/etc/sysconfig/network-scripts/”

[root@openstack network-scripts]# vi ifcfg-bond0

DEVICE=bond0

TYPE=Bond

NAME=bond0

BONDING_MASTER=yes

BOOTPROTO=none

ONBOOT=yes

IPADDR=192.168.1.70

NETMASK=255.255.255.0

GATEWAY=192.168.1.1

BONDING_OPTS="mode=5 miimon=100"

Save & exit the file.

Specify the IP address, Netmask & bonding modes as per your requirement. In my example i am using ‘mode=5′ which is used to provide fault tolerance and load balancing.

Please refer this for Different Modes in NIC bonding

Step:2 Edit the NIC interface files

For ifcfg-enp0s3

[root@openstack ~]# vi /etc/sysconfig/network-scripts/ifcfg-enp0s3

TYPE=Ethernet

BOOTPROTO=none

DEVICE=enp0s3

ONBOOT=yes

HWADDR="08:00:27:69:60:c9"

MASTER=bond0

SLAVE=yes

For ifcfg-enp0s8

[root@openstack ~]# cat /etc/sysconfig/network-scripts/ifcfg-enp0s8

TYPE=Ethernet

BOOTPROTO=none

DEVICE=enp0s8

ONBOOT=yes

HWADDR="08:00:27:ea:71:8d"

MASTER=bond0

SLAVE=yes

Step:3 Restart the Network Service

Below command will restart the network service and will bring above changes into the effect.

[root@openstack ~]# systemctl restart network.service

Step:4 Test & Verify bond interface.

Use ‘ifconfig‘ & ‘ip add‘ command to check bond interface along with its slave interfaces.

Use following command to view bond interface settings like bonding mode & slave interface.

[root@openstack ~]# cat /proc/net/bonding/bond0

Step:5 Fault tolerance testing

To test the fault tolerance we can down one interface and check whether you are still able access the server.

[root@openstack ~]# ifdown enp0s8

Device 'enp0s8' successfully disconnected.

[root@openstack ~]#