I wanted to share how i was able to throttle bandwidth

tylerdurden81

Member
Jan 8, 2011
124
0
16
After searching the forum and alot of trial and error i figured out how to throttle bandwidth. I used the script below. Where it says IF= i put the "tap id" that i got from running ifconfig. Example:

tap313i0d0 Link encap:Ethernet HWaddr 7a:71:f6:1e:0a:fb
inet6 addr: fe80::7871:f6ff:fe1e:afb/64 Scope:Link
UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1
RX packets:15232575 errors:0 dropped:0 overruns:0 frame:0
TX packets:24048846 errors:0 dropped:0 overruns:125 carrier:0
collisions:0 txqueuelen:500
RX bytes:1020621207 (973.3 MiB) TX bytes:31764432398 (29.5 GiB)

So the IF= would look like (in my case) IF=tap313i0d0 The numbered part corresponds with the VMID.
Where it says ip i put the ip of the virtual machine.
I placed this file in /etc/init.d/shape313
i run it by /etc/init.d/shape313 start

If want throttle more then one VM create a other file plug in the IF= and address= for that VM .. name the file something else and run it.

I hope this helps someone ... i know it helped me!

Code:
#!/bin/bash
#
#  tc uses the following units when passed as a parameter.
#  kbps: Kilobytes per second 
#  mbps: Megabytes per second
#  kbit: Kilobits per second
#  mbit: Megabits per second
#  bps: Bytes per second 
#       Amounts of data can be specified in:
#       kb or k: Kilobytes
#       mb or m: Megabytes
#       mbit: Megabits
#       kbit: Kilobits
#  To get the byte figure from bits, divide the number by 8 bit
#

#
# Name of the traffic control command.
TC=/sbin/tc

# The network interface we're planning on limiting bandwidth.
IF=eth0             # Interface

# Download limit (in mega bits)
DNLD=1mbit          # DOWNLOAD Limit

# Upload limit (in mega bits)
UPLD=1mbit          # UPLOAD Limit

# IP address of the machine we are controlling
IP=216.3.128.12     # Host IP

# Filter options for limiting the intended interface.
U32="$TC filter add dev $IF protocol ip parent 1:0 prio 1 u32"

start() {

# We'll use Hierarchical Token Bucket (HTB) to shape bandwidth.
# For detailed configuration options, please consult Linux man
# page.

    $TC qdisc add dev $IF root handle 1: htb default 30
    $TC class add dev $IF parent 1: classid 1:1 htb rate $DNLD
    $TC class add dev $IF parent 1: classid 1:2 htb rate $UPLD
    $U32 match ip dst $IP/32 flowid 1:1
    $U32 match ip src $IP/32 flowid 1:2

# The first line creates the root qdisc, and the next two lines
# create two child qdisc that are to be used to shape download 
# and upload bandwidth.
#
# The 4th and 5th line creates the filter to match the interface.
# The 'dst' IP address is used to limit download speed, and the 
# 'src' IP address is used to limit upload speed.

}

stop() {

# Stop the bandwidth shaping.
    $TC qdisc del dev $IF root

}

restart() {

# Self-explanatory.
    stop
    sleep 1
    start

}

show() {

# Display status of traffic control status.
    $TC -s qdisc ls dev $IF

}

case "$1" in

  start)

    echo -n "Starting bandwidth shaping: "
    start
    echo "done"
    ;;

  stop)

    echo -n "Stopping bandwidth shaping: "
    stop
    echo "done"
    ;;

  restart)

    echo -n "Restarting bandwidth shaping: "
    restart
    echo "done"
    ;;

  show)

    echo "Bandwidth shaping status for $IF:"
    show
    echo ""
    ;;

  *)

    pwd=$(pwd)
    echo "Usage: tc.bash {start|stop|restart|show}"
    ;;

esac

exit 0
 
I am probably going to write a small script for the web interface so you can do it easily through the web. Place a link on the Virtual Machine Configuration page so you can throttle that virtual machine's bandwidth.
 
I do not use OpenVZ at all so i am not sure if it will work with it. I would assume if you used the virtual nic assigned to the OpenVZ VM that it would work but i have not tested it.