The following is concluded from here.
Consider we have 2 interfaces:
eth0 & eth1
bond the two interface:
in ifcfg-eth0/ifcfg-eth1:
remove IP/MASK/GW/UUID;
DEVICE="ethn"
NM_CONTROLLED="no"
MASTER=bond0
SLAVE=yes
HWADDR="macaddr"
ONBOOT="yes"
bond0:
remove HWADDR
add IP/MASK/GW
DEVICE="bond0"
ONBOOT="yes"
BONDING_OPTS="mode=0 miimon=100 primary=eth0"
where mode=0, RR, mode=1, active-backup
miimon means milisecs after bonding is up
primary device is the default when in mode 1.
before doing anything, make sure kernel module bonding is loaded by modprobe bonding..