setup-network

#!/bin/bash


case "$1" in
  status)
    tc -s qdisc ls dev lo
    tc class show dev lo
    ;;

  on)
    if [ -z "$2" ] ; then
      echo "Usage: $0 on [#ms latency] [optional max Mbps]"
      exit 1
    fi

    # cribbed from http://serverfault.com/questions/507658/limit-incoming-and-outgoing-bandwidth-and-latency-in-linux

    if [ ! -z "$3" ] ; then
      sudo tc qdisc add dev lo handle 1: root htb default 11 
      sudo tc class add dev lo parent 1: classid 1:1 htb rate 1000Mbps
      sudo tc class add dev lo parent 1:1 classid 1:11 htb rate "$3"Mbit
      sudo tc qdisc add dev lo parent 1:11 handle 10: netem delay "$2"ms limit 100000
    else
      sudo tc qdisc add dev lo handle 1: root netem delay "$2"ms limit 100000
    fi

    ;;

  off)
    sudo tc qdisc del dev lo root 
    ;;

  *)
    echo "Use this script to add latency or bandwidth limit to the loopback device"
    echo
    echo "Usage:"
    echo "  $0 status"
    echo "  $0 on [#ms latency] [max Mpbs]"
    echo "  $0 off"
    exit 1
esac