#!/bin/bash

# lag switch, run with no arg to add lag, run with an arg to restore

IFACE=enp3s0f1
DELAYIN=900ms
LOSSIN=1%
DELAYOUT=900ms
LOSSOUT=1%

if [ "$1" != "" ]; then # lag switch off
  # out
  tc qdisc del dev "${IFACE}" root
  
  # in
  tc qdisc del dev "ifb-${IFACE}" root
  tc qdisc del dev "${IFACE}" handle ffff: ingress
  ip link set "ifb-${IFACE}" down
  ip link del "ifb-${IFACE}"
  modprobe -r ifb
else # lag switch on
  # out
  tc qdisc add dev "${IFACE}" root netem delay "${DELAYOUT}" loss "${LOSSOUT}" 25%
  
  # in
  modprobe ifb
  ip link add "ifb-${IFACE}" type ifb
  ip link set dev "ifb-${IFACE}" up
  tc qdisc add dev "${IFACE}" ingress
  tc filter add dev "${IFACE}" parent ffff: protocol ip u32 match u32 0 0 flowid 1:1 action mirred egress redirect dev "ifb-${IFACE}"
  tc qdisc add dev "ifb-${IFACE}" root netem delay "${DELAYIN}" loss "${LOSSIN}" 25%
fi