Provided by: fireqos-doc_3.1.7+ds-3_all 
NAME
fireqos-params-class - optional class parameters
SYNOPSIS
rate | commit | min speed
ceil | max speed
minrate speed
{ qdisc qdisc-name | pfifo|bfifo|sfq|fq_codel|codel|none } [options “qdisc-options”]
prio { 0..7 | keep | last }
{ linklayer linklayer-name } | { adsl {local|remote} encapsulation } | ethernet | atm
mtu bytes
mpu bytes
tsize size
overhead bytes
r2q factor
burst bytes
cburst bytes
quantum bytes
priority | balanced
input | output
DESCRIPTION
All of the options apply to interface and class statements.
Units for speeds are defined in fireqos.conf(5).
input, output
For bidirectional interfaces, input and output define the direction for which the
parameters following it are applied.
Only the following parameters are affected (all the others are applied to both input and
output):
• minrate
• rate, min, commit
• ceil, max
If one of the above is not defined for either input or output, its default will be used.
rate, commit, min
When a committed rate of speed is provided to a class, it means that the bandwidth will be
given to the class when it needs it. If the class does not need the bandwidth, it will be
available for any other class to use.
For interfaces, a rate must be defined.
For classes the rate defaults to 1/100 of the interface capacity.
ceil, max
Defines the maximum speed a class can use. Even there is available bandwidth, a class
will not exceed its ceil speed.
For interfaces, the default is the rate speed of the interface.
For classes, the defaults is the ceil of the their interfaces.
minrate
Defines the default committed speed for all classes not specifically given a rate in the
config file. It forces a recalculation of tc(8) r2q.
When minrate is not given, FireQOS assigns a default value of 1/100 of the interface rate.
qdisc qdisc-name, pfifo, bfifo, sfq, fq_codel, codel, none
The qdisc defines the method to distribute class bandwidth to its sockets. It is applied
within the class itself and is useful in cases where a class gets saturated. For
information about these, see the Traffic Control Howto (http://www.tldp.org/HOWTO/Traffic-
Control-HOWTO/classless-qdiscs.html)
A qdisc is only useful when applied to a class. It can be specified at the interface
level in order to set the default for all of the included classes.
To pass options to a qdisc, you can specify them through an environment variable or
explicitly on each class.
Set the variable FIREQOS_DEFAULT_QDISC_OPTIONS_qdiscname in the config file. For example,
for sfq:
FIREQOS_DEFAULT_QDISC_OPTIONS_sfq="perturb 10 quantum 2000".
Using this variable each sfq will get these options by default. You can still override
this by specifying explicit options for individual qdiscs, for example to add some sfq
options you would write:
class classname sfq options "perturb 10 quantum 2000"
The options keyword must appear just after the qdisc name.
prio (class)
Note
There is also a match parameter called prio, see fireqos-params-match(5).
HTB supports 8 priorities, from 0 to 7. Any number less than 0 will give priority 0. Any
number above 7 will give priority 7.
By default, FireQOS gives the first class priority 0, and increases this number by 1 for
each class it encounters in the config file. If there are more than 8 classes, all
classes after the 8th will get priority 7. In balanced mode (see balanced, below), all
classes will get priority 4 by default.
FireQOS restarts priorities for each interface and class group.
The class priority defines how the spare bandwidth is spread among the classes. Classes
with higher priorities (lower prio) will get all spare bandwidth. Classes with the same
priority will get a percentage of the spare bandwidth, proportional to their committed
rates.
The keywords keep and last will make a class use the priority of the class just above /
before it. So to make two consecutive classes have the same prio, just add prio keep to
the second one.
linklayer linklayer-name, ethernet, atm
The linklayer can only be given on interfaces. It is used by the kernel to calculate the
overheads in the packets.
adsl
adsl is a special linklayer that automatically calculates ATM overheads for the link.
local is used when linux is running PPPoE.
remote is used when PPPoE is running on the router.
Note
This special case has not yet been demonstrated for sure. Experiment a bit and if
you find out, let us know to update this page. In practice, this parameter lets
the kernel know that the packets it sees, have already an ethernet header on them.
encapsulation can be one of (all the labels on the same line are aliases):
• IPoA-VC/Mux or ipoa-vcmux or ipoa-vc or ipoa-mux,
• IPoA-LLC/SNAP or ipoa-llcsnap or ipoa-llc or ipoa-snap
• Bridged-VC/Mux or bridged-vcmux or bridged-vc or bridged-mux
• Bridged-LLC/SNAP or bridged-llcsnap or bridged-llc or bridged-snap
• PPPoA-VC/Mux or pppoa-vcmux or pppoa-vc or pppoa-mux
• PPPoA-LLC/SNAP or pppoa-llcsnap or pppoa-llc or pppoa-snap
• PPPoE-VC/Mux or pppoe-vcmux or pppoe-vc or pppoe-mux
• PPPoE-LLC/SNAP or pppoe-llcsnap or pppoe-llc or pppoe-snap
If your adsl router can give you the mtu, it would be nice to add an mtu parameter too.
For detailed info, see here (http://ace-host.stuart.id.au/russell/files/tc/tc-atm/).
mtu
Defines the MTU of the interface in bytes.
FireQOS will query the interface to find its MTU. You can overwrite this behaviour by
giving this parameter to a class or interface.
mpu
Defines the MPU of the interface in bytes.
FireQOS does not set a default value. You can set your own using this parameter.
tsize
FireQOS does not set a default size. You can set your own using this parameter.
overhead
FireQOS automatically calculates the bytes overhead for ADSL. For all other technologies,
you can specify the overhead in the config file.
r2q
FireQOS calculates the proper r2q factor, so that you can control speeds in steps of
1/100th of the interface speed (if that is possible).
Note
The HTB manual states that this parameter is ignored when a quantum have been set.
By default, FireQOS sets quantum to interface MTU, so r2q is probably is ignored by
the kernel.
burst
burst specifies the number of bytes that will be sent at once, at ceiling speed, when a
class is allowed to send traffic. It is like a `traffic unit'. A class is allowed to
send at least burst bytes before trying to serve any other class.
burst should never be lower that the interface mtu and class groups and interfaces should
never have a smaller burst value than their children. If you do specify a higher burst
for a child class, its parent may get stuck sometimes (the child will drain the parent).
By default, FireQOS lets the kernel decide this parameter, which calculates the lowest
possible value (the minimum value depends on the rate of the interface and the clock speed
of the CPU).
burst is inherited from interfaces to classes and from group classes to their subclasses.
FireQOS will not allow you to set a burst at a subclass, higher than its parent. Setting
a burst of a subclass higher than its parent will drain the parent class, which may be
stuck for up to a minute when this happens. For this check to work, FireQOS uses just its
configuration (it does not query the kernel to check how the value specified in the config
file for a subclass relates to the actual value of its parent).
cburst
cburst is like burst, but at hardware speed (not just ceiling speed).
By default, FireQOS lets the kernel decide this parameter.
cburst is inherited from interfaces to classes and from group classes to their subclasses.
FireQOS will not allow you to set a cburst at a subclass, higher to its parent. Setting a
cburst of a subclass higher than its parent, will drain the parent class, which may be
stuck for up to a minute when this happens. For this check to work, FireQOS uses just its
configuration (it does not query the kernel to check how the value specified in the config
file for a subclass relates to the actual value of its parent).
quantum
quantum specifies the number of bytes a class is allowed to send at once, when it is
borrowing spare bandwidth from other classes.
By default, FireQOS sets quantum to the interface mtu.
quantum is inherited from interfaces to classes and from group classes to their
subclasses.
priority, balanced
These parameters set the priority mode of the child classes.
priority
priority is the default mode, where FireQOS assigns an incremental priority to each
class. In this mode, the first class takes prio 0, the second prio 1, etc. When a
class has a higher prio than the others (higher = smaller number), this high
priority class will get all the spare bandwidth available, when it needs it. Spare
bandwidth will be allocate to lower priority classes only when the higher priority
ones do not need it.
balanced
balanced mode gives prio 4 to all child classes. When multiple classes have the
same prio, the spare bandwidth available is spread among them, proportionally to
their committed rate. The value 4 can be overwritten by setting
FIREQOS_BALANCED_PRIO at the top of the config file to the prio you want the
balanced mode to assign for all classes.
The priority mode can be set in interfaces and class groups. The effect is the same. The
classes that are defined as child classes, will get by default the calculated class prio
based on the priority mode given.
These options affect only the default prio that will be assigned by FireQOS. The default
is used only if you don’t explicitly use a prio parameter on a class.
Note
There is also a match parameter called priority, see fireqos-params-match(5).
SEE ALSO
• fireqos(1) - FireQOS program
• fireqos.conf(5) - FireQOS configuration file
• fireqos-interface(5) - QOS interface definition
• fireqos-class(5) - QOS class definition
• FireHOL Website (http://firehol.org/)
• FireQOS Online PDF Manual (http://firehol.org/fireqos-manual.pdf)
• FireQOS Online Documentation (http://firehol.org/documentation/)
AUTHORS
FireHOL Team.