apt-get install bridge-utils
brctl addbr br0
ifconfig eth0 0.0.0.0 down
ifconfig eth1 0.0.0.0 down
brctl addif br0 eth0
brctl addif br0 eth1
ifconfig eth0 up
ifconfig eth1 up
ifconfig br0 up

Port mirroring

apt install daemonlogger
daemonlogger -i eth1 -o eth3

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