Listing 1. tc Setup Script

#! /bin/sh
#path to tc and the ip utilities;
#change to reflect yours.
TC=./iproute2/tc/tc
IP=./iproute2/ip/ip
##################################################
#Addresses to be aliased
#change or add more to reflect yours
#
ALIAS1=10.0.0.10
ALIAS2=10.0.0.11
##################################################
# add ip aliasing support 
#uncomment if you want to use the ip utility to 
#add ip-aliasing for you
#
#$IP addr add $ALIAS1 dev eth0
#$IP addr add $ALIAS2 dev eth0
##################################################
# Attaching a device queue discipline to an 
# interface a device queue discipline is 
# equivalent almost to a device manager
#
#Attach CBQ to eth0
#Things you might need to change:
# bandwidth -- the bandwidth of the eth0 device
#   note it must match the device's real bandwidth
# allot -- it is safe to leave it at the MTU of 
#   the device
# avpkt -- the average packet size that you 
#   suspect will be seen safe to leave at 1000 
#   for Ethernet with MTU of 1514 bytes
# mpu -- minimum packet size
#
$TC qdisc add dev eth0 root handle 1: cbq \
  bandwidth 10Mbit allot 1514 cell 8 avpkt 1000\
  mpu 64
##################################################
# Attaching class queue disciplines
# bounded -- it is bound to the rate allocated;
# can't borrow even if there is a lot of idle 
# bandwidth just sitting there isolated -- cannot
# share its bandwidth to other classes prio is the 
# priority assigned 0 being the highest and 7 the 
# lowest weight -- safer to leave at 1
# queue discipline setup. Classid 1:1 will have a 
# rate of 1Mbps which is bounded.
#
$TC class add dev eth0 parent 1:0 classid 1:1 cbq\
  bandwidth 10Mbit rate 1Mbit avpkt 1000 prio 5  \
  bounded isolated allot 1514 weight 1 maxburst 21
#rate 1Mbit avpkt 1000 prio 5 bounded allot 1514 
#weight 1 maxburst 21
# Classid 1:2 will have a rate of 3Mbps which is 
#  bounded.
$TC class add dev eth0 parent 1:0 classid 1:2 cbq\
  bandwidth 10Mbit rate 3Mbit avpkt 1000 prio 5 \
  bounded allot 1514 weight 1 maxburst 21
##################################################
# Define the filter to be attached to eth0
# Create with hash table of 256 slots with ID 1:
#
$TC filter add dev eth0 parent 1:0 protocol ip\
  prio 5 handle 1: u32 divisor 256
##################################################
# define the criteria for mapping incoming packets
# to classes. Add to the 5th slot of hash table a 
# rule to select virtual address ALIAS1 direct it 
# to class 1:1 
#
$TC filter add dev eth0 parent 1:0 prio 5 u32  \
  ht 1:6: match ip src $ALIAS1 flowid 1:1 
# Add to 6th slot of hash table rule to select 
# ALIAS2 direct it to class 1:2 
$TC filter add dev eth0 parent 1:0 prio 5 u32 \
  ht 1:6: match ip src $ALIAS2 flowid 1:2 
## Lookup hash table, if it is not fragmented 
## frame. Use protocol as hash key
#
$TC filter add dev eth0 parent 1:0 prio 5 handle\
  ::1 u32 ht 800:: match ip nofrag \
  offset mask 0x0F00 shift 6 \
  hashkey mask 0x00ff0000 at 8 link 1:
#
#some more examples of how to use u32
# Add to 4th slot of hash table rule to select 
# tcp/telnet to 193.233.7.75 direct it to class 
# 1:4 and prescribe to fall to best effort,
# if traffic violates TBF (32kbit,5K)
#$TC filter add dev eth1 parent 1:0 prio 5 u32 \
#        ht 1:4: match ip dst 193.233.7.75 \
#        match tcp dst 0x17 0xffff \
#        flowid 1:4 \
#        police rate 32kbit buffer 5kb/8 mpu 64 \
#        mtu 1514 index 1
## Add to 1st slot of hash table rule to select 
## icmp to 193.233.7.75 direct it to class 1:3 
## and prescribe to fall to best effort,
## if traffic violate TBF (10kbit,5K)
#$TC filter add dev eth1 parent 1:0 prio 5 u32 \
#        ht 1:: sample ip protocol 1 0xff \
#        match ip dst 193.233.7.75 flowid 1:3 \
#        police rate 10kbit buffer 5kb/8 mpu 64\
#        mtu 1514 index 2
##################################################
#Look at all that we created:
#
echo "---- qdisc parameters ----------"
$TC qdisc ls dev eth0
echo "---- Class parameters ----------"
$TC class ls dev eth0
echo "---- filter parameters ----------"
$TC filter ls dev eth0