Bonding Network Card Ubuntu 14.04

Make sure your Cisco Switch support 802.3ad, then group 2 interface ports together

Router> enable
Router# configure terminal
Router(config)# interface port-channel 1
Router(config-if)# interface g1/0/24
Router(config-if)# channel-group 1 mode active
Router(config-if)# exit
Router(config)# interface g1/0/23
Router(config-if)# channel-group 1 mode active
Router(config-if)# end
Router# copy run start

Bonding mode: http://www.mjmwired.net/kernel/Documentation/networking/bonding.txt#508
802.3ad or 4 : IEEE 802.3ad Dynamic link aggregation. Creates aggregation groups that share the same speed and duplex settings. Utilizes all slaves in the active aggregator according to the 802.3ad specification.

Bonding network card on Ubuntu Server

apt-get install ifenslave-2.6
echo "bonding" >> /etc/modules
modprobe bonding

vi /etc/network/interface

auto em1
iface em1 inet manual
bond-master bond0
bond-primary em1

auto em2
iface em2 inet manual
bond-master bond0

auto bond0
iface bond0 inet static
bond-slaves none
bond-mode 4
bond-miimon 100
        address 192.168.1.111
        netmask 255.255.0.0
        network 192.168.0.0
        broadcast 192.168.255.255
        gateway 192.168.1.1
        dns-nameservers 192.168.1.1 

Reboot server and wait a little bit for the bond interface become active

http://www.paulmellors.net/ubuntu-server-14-04-lts-nic-bonding/
http://ilostmynotes.blogspot.com/2009/04/bridging-bonded-network-interface-on.html