Quality of Service

bandwidth egress rate

To set the bandwidth limit on the outbound traffic on a port, use the bandwidth egress rate command in the interface configuration mode. To remove the configured bandwidth limit, use the no form of the command.

[ no] bandwidth egress target-rate [ target-burst-rate ]

Syntax Description

target-rate

Specifies the bandwidth limit in Kbps.

The target rate must be a multiple of 64K and should range between 2048 and 2608832 Kbps:

It should be 2048 to 1024000 Kbps for a GE port, 2048 to 2608832 Kbps for a PON port, and 2048 to 10240000 for a 10GE port.

target-burst-rate

Specifies the burst transmission rate.

Target burst rate (Kbps) must be a multiple of 64K

Values can range between 2048 through 2608832.

Command Default

None

Command Modes

Interface Configuration (config-if)

Examples

Device#configure terminal
Device(config)#interface e1/1

Device(config-if-ethernet-1/1)#bandwidth egress 2048

clear traffic-statistic

To remove the traffic statistics records, use the clear traffic-statistic command in the global configuration mode.

clear traffic-statistic { [ all | [ ip-group { num | name } [ subitem subitem ] ] [ link-group { num | name } [ subitem subitem ] ] ] }

ip-group { num | name }

Specifies a standard or extended ACL.

link-group { num | name }

Specifies a Layer 2 ACL.

subitem subitem

Specifies the sub item in the ACL.

Command Modes

Global Configuration (config)

Command Default

None

Usage Guidelines

Use the clear traffic-statistic all command to remove all traffic statistics records.

Use the clear traffic-statistic ip-group or clear traffic-statistic link-group command to remove the traffic statistics records that are generated for the specified access control list.

Examples

Device#configure terminal
Device(config)#clear traffic-statistic ip-group 3

queue-scheduler cos-map

To map the 802.1p priorities to the hardware queue, use the queue-scheduler cos-map command in the global configuration mode. To restore the default queue scheduler settings, use the no form of the command.

[ no ] queue-scheduler cos-map [ queue-class] [ priority]

Syntax Description

queue-class

Specifies the hardware queue value which ranges from 0 through 7.

priority

Specifies the 802.1p priority. The value ranges from 0 to 7.

Command Default

Strict Priority scheduling is followed by default.

Command Modes

Global configuration (config)

Usage Guidelines

802.1p is used to classify the outgoing traffic at the egress port based on the 802.1p priority. For each message that enters the switch, the system maps the specific hardware queue priority according to the 802.1p priority of the message.

Changing the mapping relation between 802.1p priority and hardware queues changes the mapping relation between 802.1p priorities and output queues.

If two 802.1p priorities are mapped to the same hardware priority queue, messages of the two 802.1p priorities cannot be forwarded with 1:1 forwarding.

Use the queue-scheduler cos-map command to set the 802.1p mapping with hardware queue priority.

Examples

The following example shows how to map packets with priority 0 to queue 1:


Device#configure terminal
Device(config)#queue-scheduler cos-map 1 0
Config successfully.

queue-scheduler strict-priority

To configure the strict priority queue scheduling algorithm on the queue scheduler, use the queue-scheduler strict-priority command in the global configuration mode. To restore the default queue scheduler settings, use the no form of the command.

[ no ] queue-scheduler strict-priority

Command Default

Strict Priority scheduling is followed by default.

Command Modes

Global configuration (config)

Usage Guidelines

Strict-Priority Queuing is designed for critical business applications wherein the services are prioritized in order to reduce the latency of response when a congestion occurs. The priority queue classifies all messages into eight class: 7,6,5,4,3,2,1, and 0, in the order of priority. The group of critical services is put into the higher priority queue and non-critical business group is put into the lower priority queue. The higher priority queue is first emptied before the messages in the lower priority queue are sent. Messages in the group of non-critical business are transmitted in the idle gap of handling critical business data.

Examples


Device#configure terminal
Device(config)#queue-scheduler strict-priority

queue-scheduler sp-wrr

To configure strict priority and weighted round robin (WRR) queue scheduling algorithm on the queue scheduler, use the queue-scheduler sp-wrr command in the global configuration mode. To restore the default queue scheduler settings, use the no form of the command.

[ no ] queue-scheduler sp-wrr { w1| w2| w3| w4| w5| w6 | w7| w8}

Syntax Description

wx

where x can be 1, 2, 3, 4, 5, 6, 7,8

Specifies the weight of the queue represented by x.

For example, w1 represents the weight of the first queue. w2 represents the weight of the second queue.

Command Default

Strict Priority scheduling is followed by default.

Command Modes

Global configuration (config)

Usage Guidelines

Strict-Priority and WRR queue scheduling combines the algorithms of strict-priority and Weighted round robin scheduling. If the weight of the queue is set to 0, the queue follows the Strict-Priority queuing algorithm to send messages. A non-zero value of the weight puts the queue to the WRR scheduling mechanism.

Examples


Device#configure terminal
Device(config)#queue-scheduler sp-wrr 1 2 3 4 5 6 7 8

queue-scheduler wrr

To configure the weighted round robin (WRR) queue scheduling algorithm on the queue scheduler, use the queue-scheduler wrr command in the global configuration mode. To restore the default queue scheduler settings, use the no form of the command.

[ no ] queue-scheduler wrr{ w1| w2| w3| w4| w5| w6 | w7| w8}

Syntax Description

wx

where x can be 1, 2, 3, 4, 5, 6, 7,8

Specifies the weight of the queue represented by x.

For example, w1 represents the weight of the first queue. w2 represents the weight of the second queue.

Command Default

Strict Priority scheduling is followed by default.

Command Modes

Global configuration (config)

Usage Guidelines

Weighted Round Robin (WRR) queue scheduling divides each port into eight output queues: 7, 6, 5, 4, 3, 2, 1, and 0, in the that order of priority, with 7 being the highest priority. All the queues are scheduled by turns and each queue gets a certain service time. Each queue of WRR can be configured with weighted values of w7, w6, w5, w4, w3, w2, w1, or w0. The weighted value represents the weight of the resource.

An advantage of WRR queuing is that although multiple queues are scheduled by polling, each queue is not assigned a fixed time slot. If a queue is empty, it immediately switches to the next queue schedule. So, the bandwidth and resources of that queue can be fully utilized

Examples


Device#configure terminal
Device(config)#queue-scheduler wrr 1 2 3 4 5 6 7 8

queue-scheduler dscp-map

To configure the strict priority queue scheduling algorithm on the queue scheduler, use the queue-scheduler dscp-map command in the global configuration mode. To restore the default queue scheduler settings, use the no form of the command.

[ no ] queue-scheduler dscp-map [ dscp-value] [ priority]

Syntax Description

dscp-value

Specifies the DSCP value whioch ranges from 0 through 63.

priority

Specifies the 802.1p priority. The value ranges from 0 to 7.

Command Default

Strict Priority scheduling is followed by default.

Command Modes

Global configuration (config)

Usage Guidelines

DSCP mapping is disable by default. To enable DSCP mapping use the queue-scheduler dscp-map command.

DSCP allows 64 priority values whereas 802.1p (hardware queue) allows only eight priority values. By default, the following is the mapping between DSCP and 802.1p:

DSCP

802.1p

0-7

0

8-15

1

16-23

2

24-31

3

32-39

4

40-47

5

48055

6

56-63

7

Examples

The following example shoes how to map DSCP 56 to 802.1p priority 6:


Device#configure terminal
Device(config)#queue-scheduler dscp-map
 
Device(config)#queue-scheduler dscp-map 56 6

rate-limit

To set the traffic rate limit in inbound or outbound direction, use the rate-limit command in the global configuration mode. To remove the rate limit, use the no form of the command.

[ no] rate-limit { input | output } { [ ip-group { num | name } [ subitem subitem ] ] [ link-group { num | name } [ subitem subitem ] ] } target-rate

input

Specifies the rate limit in inbound direction.

output

Specifies the rate limit in outbound direction.

ip-group { num | name }

Specifies a standard or extended ACL.

link-group { num | name }

Specifies a Layer 2 ACL.

subitem subitem

Specifies the sub item in the ACL.

target-rate

Specifies target rate which is the traffic rate limit in Kbps.

Target rate should be a multiple of 64, and can range from 64 to 1048512.

Command Modes

Global Configuration (config)

Command Default

None

Usage Guidelines

Use the rate-limit input command to limit the traffic rate in the inbound direction.

Use the rate-limit output command to limit the traffic rate in the outbound direction.

Use this command to monitor the rate of traffic that enters a device. If the traffic exceeds a certain threshold, you can define policies to take suitable measures.

Examples

The following example sets the inbound traffic rate limit to 100 Kbps:

Device#configure terminal
Device(config)#rate-limit input ip-group 3 100

show bandwidth egress

To display the rate limit and the burst rate that are set for the egress interface, use the show bandwidth egress command in privileged or global configuration mode.

show bandwidth egress[ interface { ethernet | gpon } port-num]

Command Default

None

Command Modes

Privileged (#)

Global Configuration (config)

Examples

The following is a sample output of the show bandwidth command. 

Device(config)#show bandwidth egress 
g0/1: bandwidth egress
  limit rate:  / Kbps     burst:   / Kbps
 
g0/2: bandwidth egress
  limit rate:  / Kbps     burst:   / Kbps
 
g0/3: bandwidth egress
  limit rate:  / Kbps     burst:   / Kbps
 .... 
 ...
e2/2: bandwidth egress
  limit rate:  / Kbps     burst:   / Kbps

Related Commands

Command

Description

bandwidth egress rate

Sets the bandwidth limit on the outbound traffic on a port.

show qos-info all

To display the parameters that are set for Quality of Service (QoS), use the show qos-info command in privileged or global configuration mode.

show qos-info { all| traffic-copy-to-cpu | mirrored-to | traffic-priority | traffic-redirect | traffic-statistic| statistic }

Command Default

None

Command Modes

Privileged (#)

Global Configuration (config)

Usage Guidelines

Use the show qos-info all command to display all the configured QoS parameters.

Use the show qos-info statistic command to display all the statistics for QoS parameters.

Use the show qos-info traffic-copy-to-cpu command to display the parameter settings for copying messages to the CPU.

Use the show qos-info mirrored-to command to display the parameter settings for traffic mirroring.

Use the show qos-info traffic-priority command to display the parameter settings for traffic priority.

Use the show qos-info traffic-redirect command to display the parameter settings for message redirection.

Examples

Device#show qos-info all 
mirrored-to(max 3 dest port):
traffic-priority:
traffic-redirect:
traffic-statistic:
traffic-copy-to-cpu:

Here is a sample ouput for the show qos-info statistic command: 

Device#show qos-info statistic
mirrored-to:
total mirrored-to rules         : 0 rules

traffic-priority:
total traffic-priority rules    : 0 rules

traffic-redirect:
total traffic-redirect rules    : 0 rules

traffic-statistic:
total traffic-statistic rules   : 0 rules

traffic-copy-to-cpu:
total traffic-copy-to-cpu rules : 0 rules

total mirrored-to rules         : 0 rules
total traffic-priority rules    : 0 rules
total traffic-redirect rules    : 0 rules
total traffic-statistic rules   : 0 rules
total traffic-copy-to-cpu rules : 0 rules
total qos-info rules            : 0 rules

Related Commands

Command

Description

traffic-copy-to-cpu

Copies all packets to the CPU.

traffic-statistic

Configures the system to collect the traffic statistics

traffic-redirect

Redirects the traffic to a specified interface or to the CPU.

show qos-interface

To display all the policies set for Quality of Service (QoS) on the interface, use the show qos-interface command in privileged or global configuration mode.

show qos-interface { all| rate-limit | statistic

Command Default

None

Command Modes

Privileged (#)

Global Configuration (config)

Usage Guidelines

Use the show qos-interface all command to display all the QoS parameters for the interface.

Use the show qos-interface rate-limit command to display the rate limit parameters for the interface.

Use the show qos-interface statistic command to display the statistics of rate limit for all interfaces.

Examples

The following is a sample output of the show qos-interface all command: 

Device#show qos-interface all 
total qos-interface rules : 0 rules

The following is a sample output of the show qos-interface rate-limit command: 

Device#show qos-interface rate-limit
total rate-limit rules : 0 rules

The following is a sample output of the show qos-interface statistic command: 

Device#show qos-interface satistic
total qos-interface rules : 0 rules

show queue-scheduler

To display information about the queue scheduler, use the show queue-scheduler command in privileged or global configuration mode.

show queue-scheduler [ cos-map | dscp-map ]

Syntax Description

cos-map

Specifies the 802.1p and hardware queue mapping.

dscp-map

Specifies the DSCP and 802.1p value mapping.

Command Default

None

Command Modes

Privileged (#)

Global Configuration (config)

Usage Guidelines

Use the show queue-scheduler command to display information about the queue scheduler parameters.

Use the show queue-scheduler cos-map command to display information about the mapping between 802.1p and hardware.

Use the show queue-scheduler dscp-map command to display information about the mapping between 802.1p values and DSCP.

Examples

Following are sample outputs for the show queue-scheduler commands. 

Device#show queue-scheduler 
Queue scheduler status : enable
Queue scheduler mode   : SP (Strict Priority) 



Device#show queue-scheduler cos-map
Information about map of cos:
802.1P Priority  Queue of class   
-------------------------------
0                0                
1                1                
2                2                
3                3                
4                4                
5                5                
6                6                
7                7      

Device#show queue-scheduler dscp-map
dscp-pri has been disabled.

Related Commands

Command

Description

queue-scheduler wrr

Configures the weighted round robin scheduling mode.

queue-scheduler strict-priority

Configures the strict priority scheduling mode.

queue-scheduler dscp-map

Maps DSCP values to hardware priority values.

queue-scheduler cos-map

Maps 802.1p values to hardware queue map.

storm-control

To enable traffic storm control on an interface and to configure a threshold for the number of packets on the port, use thestorm-control command in the interface configuration mode. To remove the storm control configuration on an interface, use the no form of the command.

[ no] storm-control { broadcast | multicast | unicast } target-rate

Syntax Description

broadcast

Specifies broadcast traffic for storm control.

multicast

Specifies multicast traffic for storm control.

unicast

Specifies unicast traffic for storm control.

target-rate

Specifies a threshold limit for the number of packets on the port.

Value can range from 64 to 32000000 packets per second (pps)

Default value is 49984 pps

Command Default

None

Command Modes

Interface Configuration (config-if)

Examples

Device#configure terminal
Device(config)#interface e1/1

Device(config-if-ethernet-1/1)#storm-control unicast 512
Device(config-if-ethernet-1/1)#storm-control multicast 256
Device(config-if-ethernet-1/1)#storm-control broadcast 128

traffic-copy-to-cpu

To copy the packets that match an ACL to CPU, use the traffic-copy-to-cpu command in the global configuration mode. To remove the traffic copy configuration, use the no form of the command.

[ no] traffic-copy-to-cpu { [ ip-group { num | name } [ subitem subitem ] ] [ link-group { num | name } [ subitem subitem ] ] }

ip-group { num | name }

Specifies a standard or extended ACL.

link-group { num | name }

Specifies a Layer 2 ACL.

subitem subitem

Specifies the sub item in the ACL.

Command Modes

Global Configuration (config)

Command Default

None

Examples

The following example shows how to copy packets that match the subitem number 2 of ACL numbered 3 to CPU:

Device#configure terminal
Device(config)#traffic-copy-to-cpu ip-group 3 subitem 2

traffic-redirect

To redirect the messages sent to a port, use the traffic-redirect command in the global configuration mode. To remove the redirect configuration, use the no form of the command.

[ no] traffic-redirect { [ ip-group { num | name } [ subitem subitem ] ] [ link-group { num | name } [ subitem subitem ] ] [ interface interface-num | cpu] }

ip-group { num | name }

Specifies a standard or extended ACL.

link-group { num | name }

Specifies a Layer 2 ACL.

subitem subitem

Specifies the sub item in the ACL.

interface interface-num

Specifies the interface to which the traffic is redirected.

cpu

Specifies that the traffic is redirected to the CPU.

Command Modes

Global Configuration (config)

Command Default

None

Usage Guidelines

Use the traffic-redirect command to forward the traffic to an egress port or a CPU, using the specified access control list (ACL) sub items.

Examples

The following example shows how to redirect traffic to the ethernet 1/1 interface:

Device#configure terminal
Device(config)#traffic-redirect link-group link1 interface ethernet 1/1

traffic-statistic

To configure a device to collect traffic statistics, use the traffic-statistic command in in global configuration mode. To remove the traffic statistic configuration, use the no form of the command.

[ no] traffic-statistic { [ ip-group { num | name } [ subitem subitem ] ] [ link-group { num | name } [ subitem subitem ] ] }

ip-group { num | name }

Specifies a standard or extended ACL.

link-group { num | name }

Specifies a Layer 2 ACL.

subitem subitem

Specifies the sub item in the ACL.

Command Modes

Global Configuration (config)

Command Default

None

Usage Guidelines

Use this command to configure the device to collect traffic statistics. This command displays a cumulative value of the count of the number of packets that matched the ACL rule.

If you reconfigure traffic statistics, the previous information is lost.

Examples

Device#configure terminal
Device(config)#traffic-statistic ip-group 3