Quality of Service Commands: queue-limit Through set ip precedence

This chapter explains the function and syntax of the quality of service commands from queue-limit through set ip precedence . For more information about defaults and usage guidelines, see the corresponding chapter of the Cisco IOS Quality of Service Solutions Command Reference, Release 12.1.

queue-limit

To specify or modify the maximum number of packets the queue can hold for a class policy configured in a policy map, use the queue-limit policy-map class configuration command. To remove the queue packet limit from a class, use the no form of this command.

queue-limit number-of-packets

no queue-limit number-of-packets

Syntax Description

number-of-packets

A number in the range of 1 to 64 specifying the maximum number of packets that the queue for this class can accumulate.

number-of-packets	A number in the range of 1 to 64 specifying the maximum number of packets that the queue for this class can accumulate.

queue-list default

To assign a priority queue for those packets that do not match any other rule in the queue list, use the queue-list default global configuration command. To restore the default value, use the no form of this command.

queue-list list-number default queue-number

no queue-list list-number default queue-number

Syntax Description

list-number

Number of the queue list. Any number from 1 to 16.

queue-number

Number of the queue. Any number from 1 to 16. The default number of the queue list is queue number 1.

list-number	Number of the queue list. Any number from 1 to 16.
queue-number	Number of the queue. Any number from 1 to 16. The default number of the queue list is queue number 1.

queue-list interface

To establish queueing priorities on packets entering on an interface, use the queue-list interface global configuration command. To remove an entry from the list, use the no form of this command.

queue-list list-number interface interface-type interface-number queue-number

no queue-list list-number interface interface-type interface-number queue-number

Syntax Description

list-number

Number of the queue list. Any number from 1 to 16.

interface-type

Type of the interface.

interface-number

Number of the interface.

queue-number

Number of the queue. Any number from 1 to 16.

list-number	Number of the queue list. Any number from 1 to 16.
interface-type	Type of the interface.
interface-number	Number of the interface.
queue-number	Number of the queue. Any number from 1 to 16.

queue-list protocol

To establish queueing priority based upon the protocol type, use the queue-list protocol global configuration command. To remove an entry from the list, use the no form of this command with the appropriate list number.

queue-list list-number protocol protocol-name queue-number queue-keyword keyword-value

no queue-list list-number protocol protocol-name queue-number queue-keyword keyword-value

Syntax Description

list-number

Number of the queue list. Any number from 1 to 16.

protocol-name

Required argument that specifies the protocol type: aarp, apollo, appletalk, arp, bridge (transparent), clns, clns_es, clns_is, cmns, compressedtcp, decnet, decnet_node, decnet_routerl1, decnet_routerl2, dlsw, ip, ipx, pad, rsrb, stun, vines, xns, and x25.

queue-number

Number of the queue. Any number from 1 to 16.

queue-keyword keyword-value

Possible keywords are fragments, gt, list, lt, tcp, and udp.

list-number	Number of the queue list. Any number from 1 to 16.
protocol-name	Required argument that specifies the protocol type: aarp, apollo, appletalk, arp, bridge (transparent), clns, clns_es, clns_is, cmns, compressedtcp, decnet, decnet_node, decnet_routerl1, decnet_routerl2, dlsw, ip, ipx, pad, rsrb, stun, vines, xns, and x25.
queue-number	Number of the queue. Any number from 1 to 16.
queue-keyword keyword-value	Possible keywords are fragments, gt, list, lt, tcp, and udp.

queue-list queue byte-count

To specify how many bytes the system allows to be delivered from a given queue during a particular cycle, use the queue-list queue byte-count global configuration command. To return the byte count to the default value, use the no form of this command.

queue-list list-number queue queue-number byte-count byte-count-number

no queue-list list-number queue queue-number byte-count byte-count-number

Syntax Description

list-number

Number of the queue list. Any number from 1 to 16.

queue-number

Number of the queue. Any number from 1 to 16.

byte-count-number

The average number of bytes the system allows to be delivered from a given queue during a particular cycle. The default byte count is 1500 bytes.

list-number	Number of the queue list. Any number from 1 to 16.
queue-number	Number of the queue. Any number from 1 to 16.
byte-count-number	The average number of bytes the system allows to be delivered from a given queue during a particular cycle. The default byte count is 1500 bytes.

queue-list queue limit

To designate the queue length limit for a queue, use the queue-list queue limit global configuration command. To return the queue length to the default value, use the no form of this command.

queue-list list-number queue queue-number limit limit-number

no queue-list list-number queue queue-number limit limit-number

Syntax Description

list-number

Number of the queue list. Any number from 1 to 16.

queue-number

Number of the queue. Any number from 1 to 16.

limit-number

Maximum number of packets that can be enqueued at any time. The range is 0 to 32767 queue entries. A value of 0 means that the queue can be of unlimited size. The default queue is 20 entries.

list-number	Number of the queue list. Any number from 1 to 16.
queue-number	Number of the queue. Any number from 1 to 16.
limit-number	Maximum number of packets that can be enqueued at any time. The range is 0 to 32767 queue entries. A value of 0 means that the queue can be of unlimited size. The default queue is 20 entries.

random-detect (interface)

To enable Weighted Random Early Detection (WRED) or VIP-Distributed WRED (DWRED), use the random-detect interface configuration command. To configure WRED as class policy in a policy map, use the random-detect policy-map class configuration command.

To disable WRED or DWRED, use the no form of this command.

random-detect

no random-detect

Syntax Description

This command has no arguments or keywords.

random-detect (per VC)

To enable per-virtual circuit (VC) Weighted Random Early Detection (WRED) or per-VC VIP-Distributed WRED (DWRED), use the random-detect VC submode command. To disable per-VC WRED and per-VC DWRED, use the no form of this command.

random-detect [attach group-name]

no random-detect [attach group-name]

Syntax Description

attach group-name

(Optional) The name of the WRED/DWRED group.

attach group-name	(Optional) The name of the WRED/DWRED group.

random-detect exponential-weighting-constant

To configure the Weighted Random Early Detection (WRED) and VIP-Distributed WRED (DWRED) exponential weight factor for the average queue size calculation for the queue, use the random-detect exponential-weighting-constant interface configuration command.

To configure the exponential weight factor for the average queue size calculation for the queue reserved for a class, use the random-detect exponential-weighting-constant policy-map class configuration command.

To return the value to the default, use the no form of this command.

random-detect exponential-weighting-constant exponent

no random-detect exponential-weighting-constant

Syntax Description

exponent

Exponent from 1 to 16 used in the average queue size calculation.

exponent	Exponent from 1 to 16 used in the average queue size calculation.

random-detect flow

To enable flow-based Weighted Random Early Detection (WRED), use the random-detect flow interface configuration command. To disable flow-based WRED, use the no form of this command.

random-detect flow

no random-detect flow

Syntax Description

This command has no arguments or keywords.

random-detect flow average-depth-factor

To set the multiplier to be used in determining the average depth factor for a flow when flow-based Weighted Random Early Detection (WRED) is enabled, use the random-detect flow average-depth-factor interface configuration command. To remove the current flow average depth factor value, use the no form of this command.

random-detect flow average-depth-factor scaling-factor

no random-detect flow average-depth-factor scaling-factor

Syntax Description

scaling-factor

The number 2, 4, 8 or 16. The default value is 4.

scaling-factor	The number 2, 4, 8 or 16. The default value is 4.

random-detect flow count

To set the flow count for flow-based Weighted Random Early Detection (WRED), use the random-detect flow count interface configuration command. To remove the current flow count value, use the no form of this command.

random-detect flow count number

no random-detect flow count number

Syntax Description

number

Specify a value from 16 to 2¹⁵ (32768).

number	Specify a value from 16 to 2¹⁵ (32768).

random-detect-group

To define the Weighted Random Early Detection (WRED) or VIP-Distributed WRED (DWRED) parameter group, use the random-detect group global configuration command. To delete the WRED/DWRED parameter group, use the no form of this command.

random-detect-group group-name

no random-detect-group group-name

Syntax Description

group-name

Name for the WRED/DWRED parameter group.

group-name	Name for the WRED/DWRED parameter group.

random-detect precedence

To configure Weighted Random Early Detection (WRED) and VIP-Distributed WRED (DWRED) parameters for a particular IP precedence, use the random-detect precedence interface configuration command.

To configure WRED parameters for a particular IP precedence for a class policy in a policy map, use the random-detect precedence policy-map class configuration command.

To return the values to the default for the precedence, use the no form of this command.

random-detect precedence precedence min-threshold max-threshold mark-prob-denominator

no random-detect precedence precedence min-threshold max-threshold mark-prob-denominator

Syntax Description

precedence

IP precedence number. The value range is 0 to 7 and RSVP. For Cisco 7000 series routers with an RSP7000 interface processor and Cisco 7500 series routers with a VIP2-40 interface processor (VIP2-50 interface processor strongly recommended), the precedence value ranges from 0 to 7 only.

min-threshold

Minimum threshold in number of packets. The value range of this argument is 1 to 4096. When the average queue length reaches the minimum threshold, WRED randomly drops some packets with the specified IP precedence.

max-threshold

Maximum threshold in number of packets. The value range of this argument is the value of the min-threshold argument to 4096. When the average queue length exceeds the maximum threshold, WRED drops all packets with the specified IP precedence.

mark-prob-denominator

Denominator for the fraction of packets dropped when the average queue depth is at the maximum threshold. For example, if the denominator is 512, one out of every 512 packets is dropped when the average queue is at the maximum threshold. The value range is 1 to 65536. The default is 10; one out of every ten packets is dropped at the maximum threshold.

precedence	IP precedence number. The value range is 0 to 7 and RSVP. For Cisco 7000 series routers with an RSP7000 interface processor and Cisco 7500 series routers with a VIP2-40 interface processor (VIP2-50 interface processor strongly recommended), the precedence value ranges from 0 to 7 only.
min-threshold	Minimum threshold in number of packets. The value range of this argument is 1 to 4096. When the average queue length reaches the minimum threshold, WRED randomly drops some packets with the specified IP precedence.
max-threshold	Maximum threshold in number of packets. The value range of this argument is the value of the min-threshold argument to 4096. When the average queue length exceeds the maximum threshold, WRED drops all packets with the specified IP precedence.
mark-prob-denominator	Denominator for the fraction of packets dropped when the average queue depth is at the maximum threshold. For example, if the denominator is 512, one out of every 512 packets is dropped when the average queue is at the maximum threshold. The value range is 1 to 65536. The default is 10; one out of every ten packets is dropped at the maximum threshold.

rate-limit

To configure committed access rate (CAR) and Distributed CAR (DCAR) policies, use the rate-limit interface configuration command. To remove the rate limit from the configuration, use the no form of this command.

rate-limit {input | output} [access-group [rate-limit] acl-index] bps burst-normal burst-max conform-action action exceed-action action

no rate-limit {input | output} [access-group [rate-limit] acl-index] bps burst-normal burst-max conform-action action exceed-action action

Syntax Description

input

Applies this CAR traffic policy to packets received on this interface.

output

Applies this CAR traffic policy to packets sent on this interface.

access-group

(Optional) Applies this CAR traffic policy to the specified access list.

rate-limit

(Optional) The access list is a rate-limit access list.

acl-index

(Optional) Access list number.

bps

Average rate in bits per second. The value must be in increments of
8 kbps.

burst-normal

Normal burst size in bytes. The minimum value is bps divided by 2000.

burst-max

Excess burst size in bytes.

conform-action

Action to take on packets that conform to the rate limit.

action

Action to take on packets. Specify one of the following keywords:

continue---Evaluate the next rate-limit command.

drop---Drop the packet.

set-prec-continue new-prec---Set the IP precedence and evaluate the next rate-limit command.

set-prec-transmit new-prec---Set the IP precedence and transmit the packet.

transmit---Transmit the packet.

exceed-action

Action to take on packets that exceed the rate limit.

input	Applies this CAR traffic policy to packets received on this interface.
output	Applies this CAR traffic policy to packets sent on this interface.
access-group	(Optional) Applies this CAR traffic policy to the specified access list.
rate-limit	(Optional) The access list is a rate-limit access list.
acl-index	(Optional) Access list number.
bps	Average rate in bits per second. The value must be in increments of 8 kbps.
burst-normal	Normal burst size in bytes. The minimum value is bps divided by 2000.
burst-max	Excess burst size in bytes.
conform-action	Action to take on packets that conform to the rate limit.
action	Action to take on packets. Specify one of the following keywords: continue---Evaluate the next rate-limit command. drop---Drop the packet. set-prec-continue new-prec---Set the IP precedence and evaluate the next rate-limit command. set-prec-transmit new-prec---Set the IP precedence and transmit the packet. transmit---Transmit the packet.
exceed-action	Action to take on packets that exceed the rate limit.

service-policy

To attach a policy map to an input interface or virtual circuit (VC), or an output interface or VC to be used as the service policy for that interface or VC, use the service-policy global configuration command. To remove a service policy from an input or output interface or input or output VC, use the no form of this command.

service-policy {input | output} policy-map

no service-policy {input | output}

Syntax Description

input

Attaches the specified policy map to the input interface or input VC.

output

Attaches the specified policy map to the output interface or output VC.

policy-map

The name of a service policy map (created using the policy-map command) to be attached.

input	Attaches the specified policy map to the input interface or input VC.
output	Attaches the specified policy map to the output interface or output VC.
policy-map	The name of a service policy map (created using the policy-map command) to be attached.

set ip precedence

To set the precedence value in the IP header, use the set ip precedence route-map configuration command. To leave the precedence value alone, use the no form of this command.

set ip precedence [number | name]

no set ip precedence

Syntax Description

number | name

(Optional) A number or name that sets the precedence bits in the IP header.

number \| name	(Optional) A number or name that sets the precedence bits in the IP header.

set ip qos-group

To set a group ID that can be used later to classify packets, use the set ip qos-group route-map configuration command. To remove the group ID, use the no form of this command.

set ip qos-group group-id

no set ip qos-group group-id

Syntax Description

group-id

Group ID number in the range 0 to 99.

Table of Contents

Quality of Service Commands: queue-limit Through set ip precedence