[+] Setting up an Ethernet bridge in Ubuntu/Kali Linux

# Install bridge-utils
sudo apt-get install bridge-utils

# Disable network-manager + firewall

# Configuration

ifconfig
ifconfig eth0 0.0.0.0
ifconfig eth1 0.0.0.0
brctl addbr br0
brctl addif br0 eth0
brctl addif br0 eth1
ifconfig br0 up
dhclient br0

sudo tcpdump -i br0