HOW TO : Check status of bond interface in Linux

For my notes.. If you ever wanted to check the status of a bonded interface configure in Linux (esp RHEL), you can check the status by running the following command

[root@serverxyz bin]# cat /proc/net/bonding/bond0

i.e. assuming the name of your bond interface is bond0.

Output from the command

Ethernet Channel Bonding Driver: v3.4.0 (October 7, 2008)

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: eth3 (primary_reselect always)
Currently Active Slave: eth3
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: eth3
MII Status: up
Link Failure Count: 0
Permanent HW addr: 00:10:18:6e:b8:1a

Slave Interface: eth0
MII Status: up
Link Failure Count: 0
Permanent HW addr: 00:21:5e:11:34:32

The configuration files involved are

/etc/sysconfig/network-scripts/ifcfg-bond0 (Bond Interface)

DEVICE=bond0
IPADDR=10.10.40.26
NETMASK=255.255.255.0
ONBOOT=yes
BOOTPROTO=none
USERCTL=no
GATEWAY=10.10.40.1
NETWORK=10.10.40.0
BROADCAST=10.10.40.255
TYPE=Ethernet

/etc/sysconfig/network-scripts/ifcfg-eth3 (Primary Interface)

DEVICE=eth3
BOOTPROTO=none
ONBOOT=yes
HWADDR=00:10:18:6e:b8:1a
MASTER=bond0
SLAVE=yes
TYPE=Ethernet
USERCTL=no

/etc/sysconfig/network-scripts/ifcfg-eth0 (Secondary Interface)

DEVICE=eth0
HWADDR=00:21:5e:11:34:32
USERCTL=no
ONBOOT=yes
MASTER=bond0
SLAVE=yes
BOOTPROTO=none
TYPE=Ethernet