SHOREWALL-TCCLASSES(5)SHOREWALL-TCCLASSES(5)NAME
tcclasses - Shorewall file to define HTB classes
SYNOPSIS
/etc/shorewall/tcclasses
DESCRIPTION
A note on the rate/bandwidth definitions used in this file:
· don´t use a space between the integer value and the unit: 30kbit is
valid while 30 kbit is NOT.
· you can use one of the following units:
kpbs
Kilobytes per second.
mbps
Megabytes per second.
kbit
Kilobits per second.
mbit
Megabits per second.
bps or number
Bytes per second.
· if you want the values to be calculated for you depending on the
output bandwidth setting defined for an interface in tcdevices, you
can use expressions like the following:
full/3
causes the bandwidth to be calculated as 1/3 of the full
outgoing speed that is defined.
full*9/10
will set this bandwidth to 9/10 of the full bandwidth
DO NOT add a unit to the rate if it is calculated !
The columns in the file are as follows.
INTERFACE - interface[:class]
Name of interface. Each interface may be listed only once in this
file. You may NOT specify the name of an alias (e.g., eth0:0) here;
see http://www.shorewall.net/FAQ.htm#faq18
If you are running Shorewall-perl 4.1.6 or later, you may specify
the interface number rather than the interface name. If the
classify option is given for the interface in
shorewall-tcdevices[1](5), then you must also specify an interface
class (an integer that must be unique within classes associated
with this interface).
You may NOT specify wildcards here, e.g. if you have multiple ppp
interfaces, you need to put them all in here!
Please note that you can only use interface names in here that have
a bandwidth defined in the shorewall-tcdevices[1](5) file
MARK - {-|value}
The mark value which is an integer in the range 1-255. You set mark
values in the shorewall-tcrules[2](5) file, marking the traffic you
want to fit in the classes defined in here. Must be specified as
´-´ if the classify option is given for the interface in
shorewall-tcdevices[1](5)
You can use the same marks for different interfaces.
RATE - rate
The minimum bandwidth this class should get, when the traffic load
rises. If the sum of the rates in this column exceeds the
INTERFACE´s OUT-BANDWIDTH, then the OUT-BANDWIDTH limit may not be
honored.
CEIL - rate
The maximum bandwidth this class is allowed to use when the link is
idle. Useful if you have traffic which can get full speed when more
needed services (e.g. ssh) are not used.
You can use the value full in here for setting the maximum
bandwidth to the defined output bandwidth of that interface.
PRIORITY - priority
The priority in which classes will be serviced by the packet
shaping scheduler and also the priority in which bandwidth in
excess of the rate will be given to each class.
Higher priority classes will experience less delay since they are
serviced first. Priority values are serviced in ascending order
(e.g. 0 is higher priority than 1).
Classes may be set to the same priority, in which case they will be
serviced as equals.
OPTIONS (Optional) - [option[,option]...]
Added in Shorewall-perl 4.1. A comma-separated list of options
including the following:
default
This is the default class for that interface where all traffic
should go, that is not classified otherwise.
Note
You must define default for exactly one class per interface.
tos=0xvalue[/0xmask] (mask defaults to 0xff)
This lets you define a classifier for the given value/mask
combination of the IP packet´s TOS/Precedence/DiffSrv octet
(aka the TOS byte).
tos-tosname
Aliases for the following TOS octet value and mask encodings.
TOS encodings of the "TOS byte" have been deprecated in favor
of diffserve classes, but programs like ssh, rlogin, and ftp
still use them.
tos-minimize-delay 0x10/0x10
tos-maximize-throughput 0x08/0x08
tos-maximize-reliability 0x04/0x04
tos-minimize-cost 0x02/0x02
tos-normal-service 0x00/0x1e
Note
Each of these options is only valid for ONE class per
interface.
tcp-ack
If defined, causes a tc filter to be created that puts all tcp
ack packets on that interface that have a size of <=64 Bytes to
go in this class. This is useful for speeding up downloads.
Please note that the size of the ack packets is limited to 64
bytes because we want only packets WITHOUT payload to match.
Note
This option is only valid for ONE class per interface.
EXAMPLES
Example 1:
Suppose you are using PPP over Ethernet (DSL) and ppp0 is the
interface for this. You have 4 classes here, the first you can use
for voice over IP traffic, the second interactive traffic (e.g.
ssh/telnet but not scp), the third will be for all unclassified
traffic, and the forth is for low priority traffic (e.g.
peer-to-peer).
The voice traffic in the first class will be guaranteed a minimum
of 100kbps and always be serviced first (because of the low
priority number, giving less delay) and will be granted excess
bandwidth (up to 180kbps, the class ceiling) first, before any
other traffic. A single VOIP stream, depending upon codecs, after
encapsulation, can take up to 80kbps on a PPOE/DSL link, so we pad
a little bit just in case. (TOS byte values 0xb8 and 0x68 are
DiffServ classes EF and AFF3-1 respectively and are often used by
VOIP devices).
Interactive traffic (tos-minimum-delay) and TCP acks (and ICMP echo
traffic if you use the example in tcrules) and any packet with a
mark of 2 will be guaranteed 1/4 of the link bandwidth, and may
extend up to full speed of the link.
Unclassified traffic and packets marked as 3 will be guaranteed
1/4th of the link bandwidth, and may extend to the full speed of
the link.
Packets marked with 4 will be treated as low priority packets. (The
tcrules example marks p2p traffic as such.) If the link is
congested, they´re only guaranteed 1/8th of the speed, and even if
the link is empty, can only expand to 80% of link bandwidth just as
a precaution in case there are upstream queues we didn´t account
for. This is the last class to get additional bandwidth and the
last to get serviced by the scheduler because of the low priority.
#INTERFACE MARK RATE CEIL PRIORITY OPTIONS
ppp0 1 100kbit 180kbit 1 tos=0x68/0xfc,tos=0xb8/0xfc
ppp0 2 full/4 full 2 tcp-ack,tos-minimize-delay
ppp0 3 full/4 full 3 default
ppp0 4 full/8 full*8/10 4
FILES
/etc/shorewall/tcclasses
SEE ALSO
http://shorewall.net/traffic_shaping.htm
shorewall(8), shorewall-accounting(5), shorewall-actions(5),
shorewall-blacklist(5), shorewall-hosts(5), shorewall-interfaces(5),
shorewall-ipsec(5), shorewall-maclist(5), shorewall-masq(5),
shorewall-nat(5), shorewall-netmap(5), shorewall-params(5),
shorewall-policy(5), shorewall-providers(5), shorewall-proxyarp(5),
shorewall-route_rules(5), shorewall-routestopped(5),
shorewall-rules(5), shorewall.conf(5), shorewall-tcdevices(5),
shorewall-tcrules(5), shorewall-tos(5), shorewall-tunnels(5),
shorewall-zones(5)NOTES
1. shorewall-tcdevices
shorewall-tcdevices.html
2. shorewall-tcrules
shorewall-tcrules.html
09/05/2009 SHOREWALL-TCCLASSES(5)
