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@xarg
Created February 11, 2013 09:51
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Limiting traffic with tc
#!/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=512kbit # DOWNLOAD Limit
# Upload limit (in mega bits)
UPLD=512kbit # UPLOAD Limit
# IP address of the machine we are controlling
PORT=443 # Port we throttle from/to
# 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 dport $PORT 0xffff flowid 1:1
$U32 match ip sport $PORT 0xffff 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.
# see http://lartc.org/howto/lartc.qdisc.filters.html
}
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: $0 {start|stop|restart|show}"
;;
esac
exit 0
@thytetgc
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To limit SMTP, I only change PORT: 443 to PORT: 25?

@xarg
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xarg commented Jul 24, 2019

omg man, you realize this script was made 7 years ago right?

@thytetgc
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lol !! I had not seen. But it's still working ..... thanks

@xarg
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xarg commented Jul 24, 2019

proof of how good of a developer I am :))

@thytetgc
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Sorry .... but it's not working.

I was wrong.

Could you test again, and upgrade?

I liked your organization.

@zhboner
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zhboner commented Jun 1, 2020

Your script is soooooo good. I love it. Thank you @xarg

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