It can't be throw over gateway using bonding on CentOS 6
alias bond0 bonding
options bonding mode=1 miimon=200 primary=eth0

DEVICE=bond0
IPADDR=192.168.1.xxx
NETMASK=255.255.255.0
NETWORK=192.168.1.0
BROADCAST=192.168.1.255
DNS1=xxx.xxx.xxx.1
ONBOOT=yes
TYPE=Ethernet
BOOTPROTO=static
USERCTL=no
PEERDNS=no

DEVICE=eth0
ONBOOT=yes
TYPE=Ethernet
MASTER=bond0
SLAVE=yes
BOOTPROTO=static
HADDR=xx:xx:xx:xx
DNS1=xxx.xxx.xxx.1