user@server1:~$ cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: eth0 (primary_reselect always)
Currently Active Slave: eth0
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 800
Down Delay (ms): 400

Slave Interface: eth0
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 84:2b:2b:f9:73:cf
Slave queue ID: 0

Slave Interface: eth1
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 84:2b:2b:f9:73:d1
Slave queue ID: 0

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
#allow-hotplug eth0
#public bond
auto bond0
auto bond1

iface bond0 inet static
    address -
    netmask -
    gateway -
    bond-mode 1
    bond-primary eth0
    bond-slaves eth0 eth1
    bond-miimon 100
    bond-downdelay 400
    bond-updelay 800

iface bond1 inet static
    address -
    netmask 255.255.255.0
    bond-mode 1
    bond-primary eth2
    bond-slaves eth2 eth3
    bond-miimon 100
    bond-downdelay 400
    bond-updelay 800