Debian Bonding (active-backup)

sudo apt-get install ifenslave

Add to /etc/network/interfaces:

# Frontend bond interface
auto bond0
iface bond0 inet static
  address 192.168.0.11/24
  gateway 192.168.0.1
  bond-slaves enp1s0 enp3s0
  bond-mode active-backup
  bond-miimon 100
  bond-primary enp1s0 enp3s0