plq/README.md

## README.md

      
    Raw
  

              README.md
            
          
    slow

This bash script offers quick shortcuts to simulate slower network connections.  It is useful when you need to simulate a wireless network on a Linux network server, especially when you are using a virtual machine guest on your local machine or in the cloud.
slow 3G                   # Slow network on default eth0 down to 3G wireless speeds
slow 3G -l 600ms -p 10%   # slow network on eth0 and setup latency to 600ms packetloss to 10%
slow reset                # Reset connection for default eth0 to normal
slow vsat --latency=500ms # Simulate satellite internet  with a high latency
slow dsl -b 1mbps         # Simulate DSL with a slower speed than the default
slow modem-56k -d eth0    # Simulate a 56k modem on the eth1 device. eth0 is unchanged.

Credits

Richard Bullington-McGuire richard@moduscreate.com wrote the script inspired by a UI suggestion from Mike Schwartz mike@moduscreate.com.
Stack Overflow and Superuser questions that helped:

http://stackoverflow.com/questions/402377/using-getopts-in-bash-shell-script-to-get-long-and-short-command-line-options/7680682#7680682
http://superuser.com/questions/147156/simulating-a-low-bandwidth-high-latency-network-connection-on-linux

An Aptivate blog post lent some inspiration, as did this script for throttling bandwidth.
*fork version add implementation packet loss

  
## license.txt
Copyright 2012 Modus Create, Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

## slow
#!/bin/bash
#
# slow
#
# Simulates a low bandwidth, high-latency network connection
#
# Requires a Linux operating system with the 'tc' traffic control tool
#
# Author: Richard Bullington-McGuire <richard@moduscreate.com>
# Author: Mike Schwartz <mike@moduscreate.com>
#
# Copyright 2012 Modus Create, Inc.
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject
# to the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#
#
# Changelog
# ---------
#
#   0.1: first version
#   0.2: implementation packet loss by aloysius
#   0.3: add ability to use own veth device for offline testing
#
# Current url: https://gist.github.com/plq/53b4099df8e4a531593991dadc06c223
#

DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )" #"

VERSION=0.3
netns=slow
device=slow1
bandwidth=100kbit
latency=1350ms
packetloss=0%
command=slow
retcode=0
PATH=/sbin:/bin:/usr/sbin:/usr/bin

echorun() {
  echo -E '#' "$@"
  "$@"
}

if ! which tc > /dev/null; then
  echo "Aborting: No 'tc' iptables firewall traffic conditioner found" 1>&2
  echo "This requires the Linux iptables firewall." 1>&2
  exit 1
fi

if [ $EUID -ne 0 ]; then
  echo "Aborting: you must run this as root."
  exit 2
fi


# Option processing courtesy of Stack Overflow question
# http://stackoverflow.com/questions/402377/using-getopts-in-bash-shell-script-to-get-long-and-short-command-line-options/7680682#7680682
# Questioner: gagneet http://stackoverflow.com/users/35416/gagneet
# Answer: http://stackoverflow.com/a/9899366
# Answerer:  http://stackoverflow.com/users/375889/jakesandlund


while test $# -gt 0
do
  case $1 in

  # Normal option processing
    -h | --help)
      # usage and help
      command=help
      break
      ;;
    -v | --version)
      command=version
      break
      ;;
    -n | --netns)
      shift
      netnse=$1
      ;;
    -d | --device)
      shift
      device=$1
      ;;
    -b | --bandwidth)
      shift
      bandwidth=$1
      ;;
    -l | --latency)
      shift
      latency=$1
      ;;
    -p | --packetloss)
      shift
      packetloss=$1
      ;;
  # ...

  # Special cases
    --)
      break
      ;;
    --*)
      # error unknown (long) option $1
      ;;
    -?)
      # error unknown (short) option $1
      ;;
   #
   # Shortcuts
       AMPS|amps)
         command=slow
         bandwidth=14kbit
         latency=250ms
         ;;
       EDGE|edge|2.5G|GPRS|gprs)
         command=slow
         bandwidth=50kbit
         latency=200ms
         ;;
       3G|3g)
         command=slow
         bandwidth=1000kbit
         latency=200ms
         ;;
       4G|4g)
         command=slow
         bandwidth=10000kbit
         latency=100ms
         ;;
       modem-0.1k|modem-110)
         command=slow
         bandwidth=110bit
         latency=350ms
         ;;
       modem-0.3k|modem-300)
         command=slow
         bandwidth=300bit
         latency=300ms
         ;;
       modem-1.2k|modem-1200)
         command=slow
         bandwidth=1200bit
         latency=280ms
         ;;
       modem-2.4k|modem-2400)
         command=slow
         bandwidth=2400bit
         latency=250ms
         ;;
       modem-9.6k|modem-9600)
         command=slow
         bandwidth=9600bit
         latency=200ms
         ;;
       modem-14.4k|modem-14400)
         command=slow
         bandwidth=14400bit
         latency=150ms
         ;;
       modem-28.8k|modem-28800)
         command=slow
         bandwidth=28800bit
         latency=150ms
         ;;
       modem-56k|modem-56000)
         command=slow
         bandwidth=56kbit
         latency=120ms
         ;;
       56k)
         command=slow
         bandwidth=56kbit
         latency=40ms
         ;;
       T1|t1)
         command=slow
         bandwidth=1500kbit
         latency=20ms
         ;;
       T3|t3)
         command=slow
         bandwidth=45mbit
         latency=10ms
         ;;
       DSL|dsl)
         command=slow
         bandwidth=2mbit
         latency=40ms
         ;;
       cablemodem)
         command=slow
         bandwidth=10mbit
         latency=20ms
         ;;
       wifi-a|wifi-g)
         command=slow
         bandwidth=54mbit
         latency=5ms
         ;;
       wifi-b)
         command=slow
         bandwidth=11mbit
         latency=10ms
         ;;
       wifi-n)
         command=slow
         bandwidth=110mbit
         latency=2ms
         ;;
       vsat)
         command=slow
         bandwidth=5mbit
         latency=500ms
         ;;
       clear|reset)
         command=clear
         ;;
       clear-dev)
         command="clear clear-dev"
         ;;
       status)
         command=status
         break
         ;;


  # FUN STUFF HERE:
  # Split apart combined short options
    -*)
      split=$1
      shift
      set -- $(echo "$split" | cut -c 2- | sed 's/./-& /g') "$@"
      continue
      ;;

  # Done with options
    *)
      break
      ;;
  esac

  # for testing purposes:
  echo "param $1"

  shift
done

echo "netns=$netns"
echo "device=$device"
echo "command=$command"
echo "bandwidth=$bandwidth"
echo "latency=$latency"

echo $command

for c in $command; do

case $c in
  help)
    echo $0
    echo 'Usage: slow <network-type> [-d device] [-b bandwidth] [-l latency] [-p drop]'
    echo '       slow reset'
    echo '       slow status'
    echo
    echo '"network-type" type can be:'
    echo '  GPRS'
    echo '  GSM'
    echo '  EDGE'
    echo '  2.5G'
    echo '  GPRS'
    echo '  3G'
    echo '  4G'
    echo '  modem-2.4k'
    echo '  modem-9.6k'
    echo '  modem-14.4k'
    echo '  modem-28.8k'
    echo '  modem-56k'
    echo '  56k'
    echo '  T1'
    echo '  T3'
    echo '  DSL'
    echo '  cablemodem'
    echo '  wifi-a'
    echo '  wifi-b'
    echo '  wifi-g'
    echo '  wifi-n'
    echo '  eth-10'
    echo '  eth-100'
    echo '  eth-1000'
    echo '  vsat'
    echo '  vsat-busy'
    ;;
  version)
    # version info
    echo "slow version $VERSION"
    echo "Copyright (c) 2012 Modus Create"
    ;;
  slow)
    # enable forwarding
    echo "echo 1 > /proc/sys/net/ipv4/ip_forward"
    echo 1 > /proc/sys/net/ipv4/ip_forward

    # generate sudoers file if sudo is detected
    if [ -n "$SUDO_USER" ]; then
      echo sudo detected, generating sudoers.d file
      sudoers_line="$SUDO_USER ALL = (ALL) NOPASSWD: $(which ip) netns exec $netns sudo -u $SUDO_USER *"
      echo "$sudoers_line" | tee /etc/sudoers.d/99-netns-$netns
    fi

    # add device if it does not exist
    if ip link | egrep -q "^[0-9]+: $device@[^:]+:" ; then
      echo using existing network interface $device

    else
      echo adding new netns $netns
      echorun ip netns add $netns

      echo adding new veth device ${netns}0
      echorun ip link add ${netns}0 type veth peer name ${netns}1
      echorun ip link set ${netns}0 netns $netns

      # non-routed block allocated to uk dwp
      # https://news.ycombinator.com/item?id=9587746
      echorun ip netns exec $netns ip addr add dev ${netns}0 51.0.0.1/16
      echorun                      ip addr add dev ${netns}1 51.0.1.1/16
    fi

    echorun ip netns exec $netns ip link set up dev ${netns}0
    echorun                      ip link set up dev ${netns}1

    echorun ip netns exec $netns route add default gw 51.0.1.1 #dev ${netns}0

    # Credit to Superuser for the basic commands that run this
    # Question: http://superuser.com/questions/147156/simulating-a-low-bandwidth-high-latency-network-connection-on-linux
    # Author: Justin L. http://superuser.com/users/38740/justin-l
    # Answer: http://superuser.com/a/147434/159810
    if  tc qdisc show dev $device | fgrep -q "qdisc htb 1: root"; then
      verb=change
      echo "Changing existing queuing discipline"
    else
      verb=add
      echo "Adding new queuing discipline"
      echorun tc qdisc $verb dev $device root handle 1: htb default 12
    fi
    if ! lsmod | fgrep -q "sch_netem"; then
      modprobe sch_netem
    fi
    echorun tc class $verb dev $device parent 1:1 classid 1:12 htb rate $bandwidth ceil $bandwidth  &&
    echorun tc qdisc $verb dev $device parent 1:12 netem delay $latency loss $packetloss
    retcode=$?
    ;;
  clear)
    echo resetting queueing discipline
    echorun tc qdisc del dev $device root
    retcode=$?
    ;;
  clear-dev)
    if ! ip tuntap | egrep -q "^${device}:" ; then
      echo $device not a tun/tap device, not deleted.
      retcode=1;
    else
      echo deleting $device
      echorun ip tuntap del dev ${device}0 mode tap
      echorun ip tuntap del dev ${device}1 mode tap
      retcode=$?
    fi
    ;;
  status)
    echorun tc qdisc
    retcode=$?
    ;;
esac

if [ $retcode != '0' ]; then
    echorun exit $retcode
fi

done

echo
echo 1. make sure you bind your server to: 51.0.1.1
echo 2. make sure you run slowed process with: "sudo ip netns exec $netns sudo -u $USER \"<whatever>\""
echo
echo Have fun'!'
echo

exit $retcode
	Copyright 2012 Modus Create, Inc.

	Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

	The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	#!/bin/bash
	#
	# slow
	#
	# Simulates a low bandwidth, high-latency network connection
	#
	# Requires a Linux operating system with the 'tc' traffic control tool
	#
	# Author: Richard Bullington-McGuire <richard@moduscreate.com>
	# Author: Mike Schwartz <mike@moduscreate.com>
	#
	# Copyright 2012 Modus Create, Inc.
	#
	# Permission is hereby granted, free of charge, to any person obtaining
	# a copy of this software and associated documentation files (the
	# "Software"), to deal in the Software without restriction, including
	# without limitation the rights to use, copy, modify, merge, publish,
	# distribute, sublicense, and/or sell copies of the Software, and to
	# permit persons to whom the Software is furnished to do so, subject
	# to the following conditions:
	#
	# The above copyright notice and this permission notice shall be included
	# in all copies or substantial portions of the Software.
	#
	# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
	# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	#
	#
	# Changelog
	# ---------
	#
	# 0.1: first version
	# 0.2: implementation packet loss by aloysius
	# 0.3: add ability to use own veth device for offline testing
	#
	# Current url: https://gist.github.com/plq/53b4099df8e4a531593991dadc06c223
	#

	DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )" #"

	VERSION=0.3
	netns=slow
	device=slow1
	bandwidth=100kbit
	latency=1350ms
	packetloss=0%
	command=slow
	retcode=0
	PATH=/sbin:/bin:/usr/sbin:/usr/bin

	echorun() {
	echo -E '#' "$@"
	"$@"
	}

	if ! which tc > /dev/null; then
	echo "Aborting: No 'tc' iptables firewall traffic conditioner found" 1>&2
	echo "This requires the Linux iptables firewall." 1>&2
	exit 1
	fi

	if [ $EUID -ne 0 ]; then
	echo "Aborting: you must run this as root."
	exit 2
	fi


	# Option processing courtesy of Stack Overflow question
	# http://stackoverflow.com/questions/402377/using-getopts-in-bash-shell-script-to-get-long-and-short-command-line-options/7680682#7680682
	# Questioner: gagneet http://stackoverflow.com/users/35416/gagneet
	# Answer: http://stackoverflow.com/a/9899366
	# Answerer: http://stackoverflow.com/users/375889/jakesandlund


	while test $# -gt 0
	do
	case $1 in

	# Normal option processing
	-h \| --help)
	# usage and help
	command=help
	break
	;;
	-v \| --version)
	command=version
	break
	;;
	-n \| --netns)
	shift
	netnse=$1
	;;
	-d \| --device)
	shift
	device=$1
	;;
	-b \| --bandwidth)
	shift
	bandwidth=$1
	;;
	-l \| --latency)
	shift
	latency=$1
	;;
	-p \| --packetloss)
	shift
	packetloss=$1
	;;
	# ...

	# Special cases
	--)
	break
	;;
	--*)
	# error unknown (long) option $1
	;;
	-?)
	# error unknown (short) option $1
	;;
	#
	# Shortcuts
	AMPS\|amps)
	command=slow
	bandwidth=14kbit
	latency=250ms
	;;
	EDGE\|edge\|2.5G\|GPRS\|gprs)
	command=slow
	bandwidth=50kbit
	latency=200ms
	;;
	3G\|3g)
	command=slow
	bandwidth=1000kbit
	latency=200ms
	;;
	4G\|4g)
	command=slow
	bandwidth=10000kbit
	latency=100ms
	;;
	modem-0.1k\|modem-110)
	command=slow
	bandwidth=110bit
	latency=350ms
	;;
	modem-0.3k\|modem-300)
	command=slow
	bandwidth=300bit
	latency=300ms
	;;
	modem-1.2k\|modem-1200)
	command=slow
	bandwidth=1200bit
	latency=280ms
	;;
	modem-2.4k\|modem-2400)
	command=slow
	bandwidth=2400bit
	latency=250ms
	;;
	modem-9.6k\|modem-9600)
	command=slow
	bandwidth=9600bit
	latency=200ms
	;;
	modem-14.4k\|modem-14400)
	command=slow
	bandwidth=14400bit
	latency=150ms
	;;
	modem-28.8k\|modem-28800)
	command=slow
	bandwidth=28800bit
	latency=150ms
	;;
	modem-56k\|modem-56000)
	command=slow
	bandwidth=56kbit
	latency=120ms
	;;
	56k)
	command=slow
	bandwidth=56kbit
	latency=40ms
	;;
	T1\|t1)
	command=slow
	bandwidth=1500kbit
	latency=20ms
	;;
	T3\|t3)
	command=slow
	bandwidth=45mbit
	latency=10ms
	;;
	DSL\|dsl)
	command=slow
	bandwidth=2mbit
	latency=40ms
	;;
	cablemodem)
	command=slow
	bandwidth=10mbit
	latency=20ms
	;;
	wifi-a\|wifi-g)
	command=slow
	bandwidth=54mbit
	latency=5ms
	;;
	wifi-b)
	command=slow
	bandwidth=11mbit
	latency=10ms
	;;
	wifi-n)
	command=slow
	bandwidth=110mbit
	latency=2ms
	;;
	vsat)
	command=slow
	bandwidth=5mbit
	latency=500ms
	;;
	clear\|reset)
	command=clear
	;;
	clear-dev)
	command="clear clear-dev"
	;;
	status)
	command=status
	break
	;;


	# FUN STUFF HERE:
	# Split apart combined short options
	-*)
	split=$1
	shift
	set -- $(echo "$split" \| cut -c 2- \| sed 's/./-& /g') "$@"
	continue
	;;

	# Done with options
	*)
	break
	;;
	esac

	# for testing purposes:
	echo "param $1"

	shift
	done

	echo "netns=$netns"
	echo "device=$device"
	echo "command=$command"
	echo "bandwidth=$bandwidth"
	echo "latency=$latency"

	echo $command

	for c in $command; do

	case $c in
	help)
	echo $0
	echo 'Usage: slow <network-type> [-d device] [-b bandwidth] [-l latency] [-p drop]'
	echo ' slow reset'
	echo ' slow status'
	echo
	echo '"network-type" type can be:'
	echo ' GPRS'
	echo ' GSM'
	echo ' EDGE'
	echo ' 2.5G'
	echo ' GPRS'
	echo ' 3G'
	echo ' 4G'
	echo ' modem-2.4k'
	echo ' modem-9.6k'
	echo ' modem-14.4k'
	echo ' modem-28.8k'
	echo ' modem-56k'
	echo ' 56k'
	echo ' T1'
	echo ' T3'
	echo ' DSL'
	echo ' cablemodem'
	echo ' wifi-a'
	echo ' wifi-b'
	echo ' wifi-g'
	echo ' wifi-n'
	echo ' eth-10'
	echo ' eth-100'
	echo ' eth-1000'
	echo ' vsat'
	echo ' vsat-busy'
	;;
	version)
	# version info
	echo "slow version $VERSION"
	echo "Copyright (c) 2012 Modus Create"
	;;
	slow)
	# enable forwarding
	echo "echo 1 > /proc/sys/net/ipv4/ip_forward"
	echo 1 > /proc/sys/net/ipv4/ip_forward

	# generate sudoers file if sudo is detected
	if [ -n "$SUDO_USER" ]; then
	echo sudo detected, generating sudoers.d file
	sudoers_line="$SUDO_USER ALL = (ALL) NOPASSWD: $(which ip) netns exec $netns sudo -u $SUDO_USER *"
	echo "$sudoers_line" \| tee /etc/sudoers.d/99-netns-$netns
	fi

	# add device if it does not exist
	if ip link \| egrep -q "^[0-9]+: $device@[^:]+:" ; then
	echo using existing network interface $device

	else
	echo adding new netns $netns
	echorun ip netns add $netns

	echo adding new veth device ${netns}0
	echorun ip link add ${netns}0 type veth peer name ${netns}1
	echorun ip link set ${netns}0 netns $netns

	# non-routed block allocated to uk dwp
	# https://news.ycombinator.com/item?id=9587746
	echorun ip netns exec $netns ip addr add dev ${netns}0 51.0.0.1/16
	echorun ip addr add dev ${netns}1 51.0.1.1/16
	fi

	echorun ip netns exec $netns ip link set up dev ${netns}0
	echorun ip link set up dev ${netns}1

	echorun ip netns exec $netns route add default gw 51.0.1.1 #dev ${netns}0

	# Credit to Superuser for the basic commands that run this
	# Question: http://superuser.com/questions/147156/simulating-a-low-bandwidth-high-latency-network-connection-on-linux
	# Author: Justin L. http://superuser.com/users/38740/justin-l
	# Answer: http://superuser.com/a/147434/159810
	if tc qdisc show dev $device \| fgrep -q "qdisc htb 1: root"; then
	verb=change
	echo "Changing existing queuing discipline"
	else
	verb=add
	echo "Adding new queuing discipline"
	echorun tc qdisc $verb dev $device root handle 1: htb default 12
	fi
	if ! lsmod \| fgrep -q "sch_netem"; then
	modprobe sch_netem
	fi
	echorun tc class $verb dev $device parent 1:1 classid 1:12 htb rate $bandwidth ceil $bandwidth &&
	echorun tc qdisc $verb dev $device parent 1:12 netem delay $latency loss $packetloss
	retcode=$?
	;;
	clear)
	echo resetting queueing discipline
	echorun tc qdisc del dev $device root
	retcode=$?
	;;
	clear-dev)
	if ! ip tuntap \| egrep -q "^${device}:" ; then
	echo $device not a tun/tap device, not deleted.
	retcode=1;
	else
	echo deleting $device
	echorun ip tuntap del dev ${device}0 mode tap
	echorun ip tuntap del dev ${device}1 mode tap
	retcode=$?
	fi
	;;
	status)
	echorun tc qdisc
	retcode=$?
	;;
	esac

	if [ $retcode != '0' ]; then
	echorun exit $retcode
	fi

	done

	echo
	echo 1. make sure you bind your server to: 51.0.1.1
	echo 2. make sure you run slowed process with: "sudo ip netns exec $netns sudo -u $USER \"<whatever>\""
	echo
	echo Have fun'!'
	echo

	exit $retcode