Slope QoS Policy Command Reference

Command Hierarchies

Configuration Commands

config
— qos
[no] slope-policy name
description description-string
— no description
[no] exceed-slope
max-avg percent
— no max-avg
max-prob percent
— no max-prob
start-avg percent
— no start-avg
[no] shutdown
[no] high-slope
max-avg percent
— no max-avg
max-prob percent
— no max-prob
start-avg percent
— no start-avg
[no] shutdown
[no] low-slope
max-avg percent
— no max-avg
max-prob percent
— no max-prob
start-avg percent
— no start-avg
[no] shutdown

Operational Commands

config
— qos
copy slope-policy src-name dst-name [overwrite]

Show Commands

show
— qos
slope-policy [slope-policy-name] [detail]

Command Descriptions

Configuration Commands

Generic Commands

description

Syntax 
description description-string
no description
Context 
config>qos>slope-policy
Description 

This command creates a text description stored in the configuration file for a configuration context.

The description command associates a text string with a configuration context to help identify the context in the configuration file.

The no form of this command removes any description string from the context.

Default 

No description is associated with the configuration context.

Parameters 
description-string—
A text string describing the entity. Allowed values are any string up to 80 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (#, $, spaces, etc.), the entire string must be enclosed within double quotes.

Operational Commands

copy

Syntax 
copy slope-policy src-name dst-name [overwrite]
Context 
config>qos
Description 

This command copies existing QoS policy entries for a QoS policy-id to another QoS policy-id.

The copy command is a configuration level maintenance tool used to create new policies using existing policies. It also allows bulk modifications to an existing policy with the use of the overwrite keyword.

Parameters 
slope-policy—
Indicates that the source policy ID and the destination policy ID are slope policy IDs. Specify the source policy ID that the copy command will attempt to copy from and specify the destination policy ID to which the command will copy a duplicate of the policy.
overwrite—
Specifies to replace the existing destination policy. Everything in the existing destination policy will be overwritten with the contents of the source policy. If overwrite is not specified, an error will occur if the destination policy ID exists.
ALA-7>config>qos# copy slope-policy default sp1
MINOR: CLI Destination "sp1" exists - use {overwrite}.
ALA-7>config>qos#overwrite

Slope Policy QoS Commands

slope-policy

Syntax 
[no] slope-policy name
Context 
config>qos
Description 

This command enables the context to configure a QoS slope policy.

Default 

slope-policy “default”

Parameters 
name—
The name of the slope policy.
Values—
Valid names consist of any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (#, $, spaces, etc.), the entire string must be enclosed within double quotes.

time-average-factor

Syntax 
time-average-factor value
no time-average-factor
Context 
config>qos>slope-policy
Description 

This command sets a weighting factor to calculate the new shared buffer average utilization after assigning buffers for a packet entering a queue. To derive the new shared buffer average utilization, the buffer pool takes a portion of the previous shared buffer average and adds it to the inverse portion of the instantaneous shared buffer utilization.

The time-average-factor command sets the weighting factor between the old shared buffer average utilization and the current shared buffer instantaneous utilization when calculating the new shared buffer average utilization

The TAF value applies to all high and low priority RED slopes for ingress and egress access buffer pools controlled by the slope policy.

The no form of this command restores the default setting.

Default 

7 - Weighting instantaneous shared buffer utilization is 0.8%.

Parameters 
value—
Represents the Time Average Factor (TAF), expressed as a decimal integer. The value specified for TAF affects the speed at which the shared buffer average utilization tracks the instantaneous shared buffer utilization. A low value weights the new shared buffer average utilization calculation more to the shared buffer instantaneous utilization, zero using it exclusively. A high value weights the new shared buffer average utilization calculation more to the previous shared buffer average utilization value.
Values—
0 to 15

Slope Policy QoS Policy Commands

exceed-slope

Syntax 
[no] exceed-slope
Context 
config>qos>slope-policy
Description 

The exceed-slope context contains the commands and parameters for defining the exceed Random Early Detection (RED) slope graph. Each egress buffer pool supports an exceed RED slope for managing access to the shared portion of the buffer pool for exceed-profile packets.The exceed-slope parameters can be changed at any time and the affected buffer pool exceed RED slopes are adjusted appropriately.The no form of this command restores the exceed slope configuration commands to the default values. If the leaf commands within exceed-slope are set to the default parameters, the exceed-slope node will not appear in save config and show config output unless the detail parameter is present.

high-slope

Syntax 
[no] high-slope
Context 
config>qos>slope-policy
Description 

The high-slope context contains the commands and parameters for defining the high Random Early Detection (RED) slope graph. Each buffer pool supports a high RED slope for managing access to the shared portion of the buffer pool for in-profile packets.

The high-slope parameters can be changed at any time and the affected buffer pool high RED slopes will be adjusted appropriately.

The no form of this command restores the high slope configuration commands to the default values. If the commands within high-slope are set to the default parameters, the high-slope node will not appear in save config and show config output unless the detail parameter is present.

low-slope

Syntax 
[no] low-slope
Context 
config>qos>slope-policy
Description 

The low-slope context contains the commands and parameters for defining the low Random Early Detection (RED) slope graph. Each buffer pool supports a low RED slope for managing access to the shared portion of the buffer pool for low out-of-profile packets.

The low-slope parameters can be changed at any time and the affected buffer pool low RED slopes must be adjusted appropriately.

The no form of this command restores the low slope configuration commands to the default values. If the leaf commands within low-slope are set to the default parameters, the low-slope node will not appear in save config and show config output unless the detail parameter is present.

RED Slope Commands

max-avg

Syntax 
max-avg percent
no max-avg
Context 
config>qos>slope-policy>exceed-slope
config>qos>slope-policy>high-slope
config>qos>slope-policy>low-slope
Description 

Sets the exceed, low, or high Random Early Detection (RED) slope position for the shared buffer average utilization value where the packet discard probability rises directly to one. The percent parameter is expressed as a percentage of the shared buffer size.

The no form of this command restores the max-avg value to the default setting. If the current start-avg setting is larger than the default, an error will occur and the max-avg setting will not be changed to the default.

Default 

max-avg 90 — High slope default is 90% buffer utilization before discard probability is 1.

max-avg 75 — Low slope default is 75% buffer utilization before discard probability is 1.

max-avg 55 — Exceed slope default is 55% buffer utilization before discard probability is 1.

Parameters 
percent—
The percentage of the shared buffer space for the buffer pool at which point the drop probability becomes 1. The value entered must be greater or equal to the current setting of start-avg. If the entered value is smaller than the current value of start-avg, an error will occur and no change will take place.
Values—
0 to 100

max-prob

Syntax 
max-prob percent
no max-prob
Context 
config>qos>slope-policy>exceed-slope
config>qos>slope-policy>high-slope
config>qos>slope-policy>low-slope
Description 

Sets the exceed, low, or high Random Early Detection (RED) slope position for the maximum non-one packet discard probability value before the packet discard probability rises directly to one. The percent parameter is expressed as a percentage of packet discard probability where always discard is a probability of 1. A max-prob value of 80 represents 80% of 1, or a packet discard probability of 0.8.

The no form of this command restores the max-prob value to the default setting.

Default 

max-prob 80 to 80% maximum drop probability corresponding to the max-avg.

Parameters 
percent—
The maximum drop probability percentage corresponding to the max-avg, expressed as a decimal integer.
Values—
0 to 100

shutdown

Syntax 
[no] shutdown
Context 
config>qos>slope-policy>exceed-slope
config>qos>slope-policy>high-slope
config>qos>slope-policy>low-slope
Description 

This command enables or disables the administrative status of the Random Early Detection slope.

By default, all slopes are shutdown and have to be explicitly enabled (no shutdown).

The no form of this command administratively enables the RED slope.

Default 

shutdown - RED slope disabled implying a zero (0) drop probability

start-avg

Syntax 
start-avg percent
no start-avg
Context 
config>qos>slope-policy>exceed-slope
config>qos>slope-policy>high-slope
config>qos>slope-policy>low-slope
Description 

This command sets the exceed, low, or high Random Early Detection (RED) slope position for the shared buffer average utilization value where the packet discard probability starts to increase above zero. The percent parameter is expressed as a percentage of the shared buffer size.

The no form of this command restores the start-avg value to the default setting. If the max-avg setting is smaller than the default, an error will occur and the start-avg setting will not be changed to the default.

Default 

start-avg 70 — High slope default is 70% buffer utilization before discard probability starts to increase above zero.

start-avg 50 — Low slope default is 50% buffer utilization before discard probability starts to increase above zero.

start-avg 30 — Exceed slope default is 30% buffer utilization before discard probability starts to increase above zero

Parameters 
percent—
The percentage of the shared buffer space for the buffer pool at which point the drop probability starts to increase above zero. The value entered must be less than or equal to the current setting of max-avg. If the entered value is greater than the current value of max-avg, an error will occur and no change will take place.
Values—
0 to 100

Show Commands

slope-policy

Syntax 
slope-policy [slope-policy-name] [detail]
Context 
show>qos
Description 

This command displays slope policy information.

Parameters 
slope-policy-name—
The name of the slope policy.
detail—
Displays detailed information about the slope policy.
Output 
Slope QoS Policy Output Fields

The following table describes slope QoS policy output fields.

Table 42:  Show QoS Slope Policy Output Fields   

Label

Description

Policy

The ID that uniquely identifies the policy.

Description

A string that identifies the policy’s context in the configuration file.

Time Avg

The weighting between the previous shared buffer average utilization result and the new shared buffer utilization.

Slope Parameters

Start Avg

Specifies the RED slope position for the shared buffer average utilization value where the packet discard probability starts to increase above zero.

Max Avg

Specifies the percentage of the shared buffer space for the buffer pool at which point the drop probability becomes 1, expressed as a decimal integer

Admin State

Enabled

The administrative status of the RED slope is enabled.

Disabled

The administrative status of the RED slope is disabled.

Max Prob.

Specifies the RED slope position for the maximum non-one packet discard probability value before the packet discard probability rises directly to one.

Sample Output
A:C# show qos slope-policy “2”
===============================================================================
QoS Slope Policy
===============================================================================
Policy : 2
Time Avg : 7
-------------------------------------------------------------------------------
High Slope Parameters
-------------------------------------------------------------------------------
Start Avg : 70 Admin State : Enabled
Max Avg : 90 Max Prob. : 100
-------------------------------------------------------------------------------
Low Slope Parameters
-------------------------------------------------------------------------------
Start Avg : 30 Admin State : Enabled
Max Avg : 40 Max Prob. : 100
-------------------------------------------------------------------------------
Exceed Slope Parameters
-------------------------------------------------------------------------------
Start Avg : 10 Admin State : Disabled
Max Avg : 25 Max Prob. : 100
===============================================================================
A:C# show qos slope-policy 2 detail
===============================================================================
QoS Slope Policy
===============================================================================
Policy : 2
Time Avg : 7
-------------------------------------------------------------------------------
High Slope Parameters
-------------------------------------------------------------------------------
Start Avg : 70 Admin State : Enabled
Max Avg : 90 Max Prob. : 100
-------------------------------------------------------------------------------
Low Slope Parameters
-------------------------------------------------------------------------------
Start Avg : 30 Admin State : Enabled
Max Avg : 40 Max Prob. : 100
-------------------------------------------------------------------------------
Exceed Slope Parameters
-------------------------------------------------------------------------------
Start Avg : 10 Admin State : Disabled
Max Avg : 25 Max Prob. : 100
-------------------------------------------------------------------------------
Associations
-------------------------------------------------------------------------------
Object Type Object Id Application Pool
-------------------------------------------------------------------------------
Port 1/1/1 Acc-Egr default
-------------------------------------------------------------------------------
Named-Pool Associations
-------------------------------------------------------------------------------
Policy-Name Pool-Name
-------------------------------------------------------------------------------
No Matching Entries
-------------------------------------------------------------------------------
WRED Slot/FP Associations
-------------------------------------------------------------------------------
Slot FP
-------------------------------------------------------------------------------
No Matching Entries
-------------------------------------------------------------------------------
WRED SAP Queue Associations
-------------------------------------------------------------------------------
Policy-Id Queue-Id
-------------------------------------------------------------------------------
No Matching Entries
-------------------------------------------------------------------------------
WRED QoS Queue-Group Associations
-------------------------------------------------------------------------------
Queue-Group Queue-Id
-------------------------------------------------------------------------------
No Matching Entries
===============================================================================
A:C#