Consolidated Platform Command Reference, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)

class

To define a traffic classification match criteria for the specified class-map name, use the class command in policy-map configuration mode. Use the no form of this command to delete an existing class map.

class { class-map-name | class-default }

no class { class-map-name | class-default }

Syntax Description

class-map-name	Assigns a name to the class map.
class-default	Refers to a system default class that matches unclassified packets.

Command Default

No policy map class-maps are defined.

Command Modes

Policy-map configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Before using the class command, you must use the policy-map global configuration command to identify the policy map and enter policy-map configuration mode. After specifying a policy map, you can configure a policy for new classes or modify a policy for any existing classes in that policy map. You attach the policy map to a port by using the service-policy interface configuration command.

After entering the class command, you enter policy-map class configuration mode. These configuration commands are available:

exit—Exits policy-map class configuration mode and returns to policy-map configuration mode.
no—Returns a command to its default setting.
police—Defines a policer or aggregate policer for the classified traffic. The policer specifies the bandwidth limitations and the action to take when the limits are exceeded. For more information, see police and police aggregate.
set—Specifies a value to be assigned to the classified traffic. For more information, see set.
trust—Defines a trust state for traffic classified with the class or the class-map command. For more information, see trust.

To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.

The class command performs the same function as the class-map global configuration command. Use the class command when a new classification, which is not shared with any other ports, is needed. Use the class-map command when the map is shared among many ports.

You can configure a default class by using the class class-default policy-map configuration command. Unclassified traffic (traffic that does not meet the match criteria specified in the traffic classes) is treated as default traffic.

Examples

This example shows how to configure a default traffic class to a policy map:

Switch# configure terminal 
Switch(config)# class-map cm-3
Switch(config-cmap)# match ip dscp 30
Switch(config-cmap)# match protocol ipv6
Switch(config-cmap)# exit
Switch(config)# class-map cm-4
Switch(config-cmap)# match ip dscp 40
Switch(config-cmap)# match protocol ip
Switch(config-cmap)# exit
Switch(config)# policy-map pm3
Switch(config-pmap)# class class-default
Switch(config-pmap-c)# set dscp 10
Switch(config-pmap-c)# exit
Switch(config-pmap)# class cm-3
Switch(config-pmap-c) set dscp 4
Switch(config-pmap-c)# exit
Switch(config-pmap)# class cm-4
Switch(config-pmap-c)# trust cos
Switch(config-pmap-c)# exit
Switch(config-pmap)# exit

You can verify your settings by entering the show policy-map privileged EXEC command.

This example shows how the default traffic class is automatically placed at the end of policy-map pm3 even though class-default was configured first:

Switch# show policy-map pm3
  Policy Map pm3
    Class cm-3
      set dscp 4
    Class cm-4
      trust cos
    Class class-default
      set dscp 10
Switch#

Related Commands

Command	Description
class-map	Creates a class map to be used for matching packets to the class whose name you specify.
police	Defines a policer for classified traffic.
policy map	Defines a policer for classified traffic.
set	Classifies IP traffic by setting a DSCP or IP-precedence value in the packet.
show policy-map	Displays quality of service (QoS) policy maps.
trust	Defines a trust state for the traffic classified through the class policy-map configuration command or the class-map global configuration command.

class-map

To create a class map to be used for matching packets to the class whose name you specify and to enter class-map configuration mode, use the class-map command in global configuration mode. Use the no form of this command to delete an existing class map and to return to global or policy map configuration mode.

class-map [ match-any | type] class-map-name

no class-map [ match-any | type] class-map-name

Syntax Description

match-any	(Optional) Performs a logical-OR of the matching statements under this class map. One or more criteria must be matched.
type	(Optional) Configures the CPL class map.
class-map-name	Name of the class for the class map. The class name is used for both the class map and to configure a policy for the class in the policy map.

Command Default

No class maps are defined.

Command Modes

Global configuration

Policy map configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

The class-map command and its subcommands are used to define packet classification, marking, and aggregate policing as part of a globally named service policy applied on a per-port basis.

After you are in quality of service (QoS) class-map configuration mode, these configuration commands are available:

description—Describes the class map (up to 200 characters). The show class-map privileged EXEC command displays the description and the name of the class map.
exit—Exits from QoS class-map configuration mode.
match—Configures classification criteria. For more information, see the match (class-map configuration) .
no—Removes a match statement from a class map.

If you enter the match-any keyword, you can only use it to specify an extended named access control list (ACL) with the match access-group class-map configuration command.

To define packet classification on a physical-port basis, only one match command per class map is supported.

Only one ACL can be configured in a class map. The ACL can have multiple access control entries (ACEs).

Examples

This example shows how to configure the class map called class1 with one match criterion, which is an access list called 103:

Switch(config)# access-list 103 permit ip any any dscp 10
Switch(config)# class-map class1
Switch(config-cmap)# match access-group 103
Switch(config-cmap)# exit

This example shows how to delete the class map class1:

Switch(config)# no class-map class1

You can verify your settings by entering the show class-map privileged EXEC command.

Related Commands

Command	Description
class	Defines a traffic classification match criteria (through the police, set, and trust policy-map class configuration commands) for the specified class-map name.
match (class-map configuration)	Defines the match criteria to classify traffic.
policy map	Creates or modifies a policy map that can be attached to multiple ports to specify a service policy.
show class-map	Displays QoS class maps.

debug qos

To enable debugging of the quality of service (QoS) software, use the debug qos in privileged EXEC mode. Use the no form of this command to disable QoS debugging.

debug qos { capability | command-installation-time | events | index | pre-classify | provision | service-policy | set | snmp | tunnel_marking }

no debug qos { capability | command-installation-time | events | index | pre-classify | provision | service-policy | set | snmp | tunnel_marking }

Syntax Description

capability	Displays all QoS capability debug messages.
command-installation-time	Displays the amount of time the QoS command takes to become effective.
events	Displays QoS MQC events.
index	Displays class-based QoS MIB index persistency.
pre-classify	Displays QoS pre-classify events for VPN.
provision	Displays QoS provisions.
service-policy	Displays QoS service policies.
set	Displays QoS packet marking.
snmp	Displays class-based QoS configuration and statistics information.
tunnel_marking	Displays QoS packet tunnel marking.

Command Default

Debugging is disabled.

Command Modes

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

The undebug qos command is the same as the no debug qos command.

When you enable debugging on a switch stack, it is enabled only on the stack master. To enable debugging on a stack member, you can start a session from the stack master by using the session switch-number privileged EXEC command, then enter the debug command at the command-line prompt of the stack member. You also can use the remote command stack-member-number LINE privileged EXEC command on the stack master switch to enable debugging on a member switch without first starting a session.

Related Commands

Command	Description
show debugging	Displays information about the types of debugging that are enabled.

match (class-map configuration)

To define the match criteria to classify traffic, use the match command in class-map configuration mode. Use the no form of this command to remove the match criteria.

match { access-group acl-index-or-name | ip { dscp dscp-list | precedence ip-precedence-list } | protocol { arp | cdp | http | ip | ipv6 } }

no match { access-group acl-index-or-name | ip { dscp dscp-list | precedence ip-precedence-list } | protocol { arp | cdp | http | ip | ipv6 } }

Syntax Description

access-group acl-index-or-name

Specifies the number or name of an access control list (ACL).

The range is from 1 to 2799.

ip

Sets IP specific values.

dscp dscp-list—Lists up to eight IP Differentiated Services Code Point (DSCP) values to match against incoming packets. Separate each value with a space. The range is 0 to 63. You also can enter a mnemonic name for a commonly used value.
precedence ip-precedence-list—Lists up to eight IP-precedence values to match against incoming packets. Separate each value with a space. The range is 0 to 7. You also can enter a mnemonic name for a commonly used value.

protocol

Specifies the name of a protocol to be used as the match criteria against which packets are checked to determine if they belong to the class specified by the class map.

The following protocols are supported: arp,cdp, http, ip, and ipv6.

Command Default

No match criteria are defined.

Command Modes

Class-map configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

The match command is used to specify which fields in the incoming packets are examined to classify the packets. Only the IP access group or the MAC access group matching to the Ether Type/Len are supported.

If you enter the class-map match-any class-map-name global configuration command, you can enter the following match commands:

match access-group name acl-name
match ip dscp dscp-list
match ip precedence ip-precedence-list

You cannot enter the match access-group acl-index command.

For the match ip dscp dscp-list or the match ip precedence ip-precedence-list command, you can enter a mnemonic name for a commonly used value. For example, you can enter the match ip dscp af11 command, which is the same as entering the match ip dscp 10 command. You can enter the match ip precedence critical command, which is the same as entering the match ip precedence 5 command. For a list of supported mnemonics, enter the match ip dscp ? or the match ip precedence ? command to see the command-line help strings.

You can verify your settings by entering the show class-map privileged EXEC command.

Examples

This example shows how to create a class map called class2, which matches all the incoming traffic with DSCP values of 10, 11, and 12:

Switch(config)# class-map class2
Switch(config-cmap)# match ip dscp 10 11 12
Switch(config-cmap)# exit

This example shows how to create a class map called class3, which matches all the incoming traffic with IP-precedence values of 5, 6, and 7:

Switch(config)# class-map class3
Switch(config-cmap)# match ip precedence 5 6 7 
Switch(config-cmap)# exit

This example shows how to delete the IP-precedence match criteria and to classify traffic using acl1:

Switch(config)# class-map class2
Switch(config-cmap)# match ip precedence 5 6 7 
Switch(config-cmap)# no match ip precedence
Switch(config-cmap)# match access-group acl1
Switch(config-cmap)# exit

Related Commands

Command	Description
class-map	Creates a class map to be used for matching packets to the class whose name you specify.
show class-map	Displays quality of service (QoS) class maps.

mls qos

To enable quality of service (QoS) for the entire switch, use the mls qos command in global configuration mode. Use the no form of this command to reset all the QoS-related statistics and to disable the QoS features for the entire switch.

mls qos

no mls qos

Syntax Description

This command has no arguments or keywords.

Command Default

QoS is disabled. There is no concept of trusted or untrusted ports because the packets are not modified (the CoS, DSCP, and IP precedence values in the packet are not changed). Traffic is switched in pass-through mode (packets are switched without any rewrites and classified as best effort without any policing).

When QoS is enabled with the mls qos global configuration command and all other QoS settings are set to their defaults, traffic is classified as best effort (the DSCP and CoS value is set to 0) without any policing. No policy maps are configured. The default port trust state on all ports is untrusted. The default egress queue settings are in effect.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

When the mls qos command is entered, QoS is enabled with the default parameters on all ports in the system.

QoS must be globally enabled to use QoS classification, policing, marking or dropping, queueing, and traffic shaping features. You can create a policy map and attach it to a port before entering the mls qos command. QoS processing is disabled until you enter the mls qos command.

When you enter the no mls qos command, policy maps and class maps that are used to configure QoS are not deleted from the configuration, but entries corresponding to policy maps are removed from the switch hardware to save system resources. To reenable QoS with the previous configurations, enter the mls qos command.

Toggling the QoS status of the switch with this command modifies (reallocates) the sizes of the queues. During the queue size modification, the queue is temporarily shut down during the hardware reconfiguration, and the switch drops newly arrived packets for this queue.

Examples

This example shows how to enable QoS on the switch:

Switch(config)# mls qos

You can verify your settings by entering the show mls qos privileged EXEC command.

Related Commands

Command	Description
show mls qos	Displays QoS information.

mls qos aggregate-policer

To define policer parameters that can be shared by multiple classes within the same policy map, use the mls qos aggregate-policer command in global configuration mode. Use the no form of this command to delete an aggregate policer.

mls qos aggregate-policer aggregate-policer-name rate-bps burst-byte exceed-action { drop | policed-dscp-transmit }

no mls qos aggregate-policer aggregate-policer-name rate-bps burst-byte { drop | policed-dscp-transmit }

Syntax Description

aggregate-policer-name	The name of the aggregate policer as referenced by the police aggregate policy-map class configuration command.
rate-bps	The average traffic rate in bits per second (b/s). The range is 8000 to 10000000000.
burst-byte	The normal burst size in bytes. The range is 8000 to 1000000.
exceed-action drop	Sets the traffic rate. If the rate is exceeded, the switch drops the packet.
exceed-action policed-dscp-transmit	Sets the traffic rate. If the rate is exceeded, the switch changes the Differentiated Services Code Point (DSCP) of the packet to that specified in the policed-DSCP map and then sends the packet.

Command Default

No aggregate policers are defined.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

A policer defines a maximum permissible rate of transmission, a maximum burst size for transmissions, and an action to take if either maximum is exceeded.

Define an aggregate policer if the policer is shared with multiple classes.

Policers for a port cannot be shared with other policers for another port; traffic from two different ports cannot be aggregated for policing purposes.

The port ASIC device, which controls more than one physical port, supports 256 policers on the switch (255 user-configurable policers plus 1 policer reserved for internal use). The maximum number of configurable policers supported per port is 63. Policers are allocated on demand by the software and are constrained by the hardware and ASIC boundaries. You cannot reserve policers per port (there is no guarantee that a port will be assigned to any policer).

You apply an aggregate policer to multiple classes in the same policy map; you cannot use an aggregate policer across different policy maps.

You cannot delete an aggregate policer if it is being used in a policy map. You must first use the no police aggregate aggregate-policer-name policy-map class configuration command to delete the aggregate policer from all policy maps before using the no mls qos aggregate-policer aggregate-policer-name command.

Policing uses a token-bucket algorithm. You configure the bucket depth (the maximum burst that is tolerated before the bucket overflows) by using the burst-byte option of the police policy-map class configuration command or the mls qos aggregate-policer global configuration command. You configure how fast (the average rate) that the tokens are removed from the bucket by using the rate-bps option of the police policy-map class configuration command or the mls qos aggregate-policer global configuration command. For more information, see the software configuration guide for this release.

Examples

This example shows how to define the aggregate policer parameters and how to apply the policer to multiple classes in a policy map:

Switch(config)# mls qos aggregate-policer agg_policer1 1000000 1000000 exceed-action drop
Switch(config)# policy-map policy2
Switch(config-pmap)# class class1
Switch(config-pmap-c)# police aggregate agg_policer1
Switch(config-pmap-c)# exit
Switch(config-pmap)# class class2 
Switch(config-pmap-c)# set dscp 10
Switch(config-pmap-c)# police aggregate agg_policer1
Switch(config-pmap-c)# exit
Switch(config-pmap)# class class3
Switch(config-pmap-c)# trust dscp
Switch(config-pmap-c)# police aggregate agg_policer2
Switch(config-pmap-c)# exit

You can verify your settings by entering the show mls qos aggregate-policer privileged EXEC command.

Related Commands

Command	Description
police aggregate	Creates a policer that is shared by different classes.
show mls qos aggregate-policer	Displays the quality of service (QoS) aggregate policer configuration.

mls qos cos

To define the default class of service (CoS) value of a port or to assign the default CoS to all incoming packets on the port, use the mls qos cos command in interface configuration mode. Use the no form of this command to return to the default setting.

mls qos cos { default-cos | override }

no qos mls cos { default-cos | override }

Syntax Description

default-cos	The default CoS value that is assigned to a port. If packets are untagged, the default CoS value becomes the packet CoS value. The CoS range is 0 to 7.
override	Overrides the CoS value of the incoming packets, and apply the default CoS value on the port to all incoming packets.

Command Default

The default CoS value for a port is 0.

CoS override is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

You can use the default value to assign a CoS and Differentiated Services Code Point (DSCP) value to all incoming packets that are untagged (if the incoming packet does not have a CoS value). You also can assign a default CoS and DSCP value to all incoming packets by using the override keyword.

Use the override keyword when all incoming packets on certain ports deserve higher or lower priority than packets entering from other ports. Even if a port is previously set to trust DSCP, CoS, or IP precedence, this command overrides the previously configured trust state, and all the incoming CoS values are assigned the default CoS value configured with the mls qos cos command. If an incoming packet is tagged, the CoS value of the packet is modified with the default CoS of the port at the ingress port.

Examples

This example shows how to configure the default port CoS to 4 on a port:

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# mls qos trust cos
Switch(config-if)# mls qos cos 4

This example shows how to assign all the packets entering a port to the default port CoS value of 4 on a port:

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# mls qos cos 4
Switch(config-if)# mls qos cos override

You can verify your settings by entering the show mls qos interface privileged EXEC command.

Related Commands

Command	Description
show mls qos interface	Displays quality of service (QoS) information.

mls qos dscp-mutation

To apply a Differentiated Services Code Point (DSCP)-to-DSCP-mutation map to a DSCP-trusted port, use the mls qos dscp-mutation command in interface configuration mode. Use the no form of this command to return the map to the default settings.

mls qos dscp-mutation dscp-mutation-name

no mls qos dscp-mutation dscp-mutation-name

Syntax Description

dscp-mutation-name

The name of the DSCP-to-DSCP-mutation map. This map was previously defined with the mls qos map dscp-mutation global configuration command.

Command Default

The default DSCP-to-DSCP-mutation map is a null map, which maps incoming DSCPs to the same DSCP values.

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

If two quality of service (QoS) domains have different DSCP definitions, use the DSCP-to-DSCP-mutation map to translate one set of DSCP values to match the definition of another domain. You apply the DSCP-to-DSCP-mutation map to the receiving port (ingress mutation) at the boundary of a QoS administrative domain.

With ingress mutation, the new DSCP value overwrites the one in the packet, and QoS handles the packet with this new value. The switch sends the packet out the port with the new DSCP value.

You can configure multiple DSCP-to-DSCP-mutation maps on ingress ports.

You apply the map only to DSCP-trusted ports. If you apply the DSCP mutation map to an untrusted port, to CoS or IP-precedence trusted port, the command has no immediate effect until the port becomes DSCP-trusted.

Examples

This example shows how to define the DSCP-to-DSCP mutation map named dscpmutation1 and to apply the map to a port:

Switch(config)# mls qos map dscp-mutation dscpmutation1 10 11 12 13 to 30
Switch(config)# interface gigabitethernet3/0/1
Switch(config-if)# mls qos trust dscp
Switch(config-if)# mls qos dscp-mutation dscpmutation1

This example shows how to remove the DSCP-to-DSCP mutation map name dscpmutation1 from the port and to reset the map to the default:

Switch(config-if)# no mls qos dscp-mutation dscpmutation1

You can verify your settings by entering the show mls qos maps privileged EXEC command.

Related Commands

Command	Description
mls qos map	Defines the DSCP-to-DSCP mutation map.
mls qos trust	Configures the port trust state.
show mls qos maps	Displays QoS mapping information.

mls qos map

To define the class of service (CoS)-to-Differentiated Services Code Point (DSCP) map, DSCP-to-CoS map, the DSCP-to-DSCP-mutation map, the IP-precedence-to-DSCP map, and the policed-DSCP map, use the mls qos map command in global configuration mode. Use the no form of this command to return to the default map.

mls qos map { cos-dscp dscp1 . .. dscp8 | dscp-cos dscp-list to cos | dscp-mutation dscp-mutation-name in-dscp to out-dscp | ip-prec-dscp dscp1 . .. dscp8 | policed-dscp dscp-list to mark-down-dscp }

no mls qos map { cos-dscp dscp1 . .. dscp8 | dscp-cos dscp-list to cos | dscp-mutation dscp-mutation-name in-dscp to out-dscp | ip-prec-dscp dscp1 . .. dscp8 | policed-dscp dscp-list to mark-down-dscp }

Syntax Description

cos-dscp dscp1...dscp8	Defines the CoS-to-DSCP map. For dscp1...dscp8, enter eight DSCP values that correspond to CoS values 0 to 7. Separate each DSCP value with a space. The range is 0 to 63.
dscp-cos dscp-list to cos	Defines the DSCP-to-CoS map. For dscp-list, enter up to eight DSCP values, with each value separated by a space, then enter the to keyword. The range is 0 to 63. For cos, enter a single CoS value to which the DSCP values correspond. The range is 0 to 7.
dscp-mutation dscp-mutation-name in-dscp to out-dscp	Defines the DSCP-to-DSCP-mutation map. For dscp-mutation-name, enter the mutation map name. For in-dscp, enter up to eight DSCP values, with each value separated by a space, then enter the to keyword. For out-dscp, enter a single DSCP value. The range is 0 to 63.
ip-prec-dscp dscp1...dscp8	Defines the IP-precedence-to-DSCP map. For dscp1...dscp8, enter eight DSCP values that correspond to the IP precedence values 0 to 7. Separate each DSCP value with a space. The range is 0 to 63.
policed-dscp dscp-list to mark-down-dscp	Defines the policed-DSCP map. For dscp-list, enter up to eight DSCP values, with each value separated by a space, then enter the to keyword. For mark-down-dscp, enter the corresponding policed (marked down) DSCP value. The range is 0 to 63.

Command Default

For the default CoS-to-DSCP map, see Table 1.
For the default DSCP-to-CoS map, see Table 2.
For the default IP-precedence-to-DSCP map, see Table 3.

When this command is disabled, the default maps are set.

The default DSCP-to-DSCP-mutation map is a null map, which maps an incoming DSCP value to the same DSCP value.

The default policed-DSCP map is a null map, which maps an incoming DSCP value to the same DSCP value.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

All the maps are globally defined. All the maps, except the DSCP-to-DSCP-mutation map, are applied to all ports. The DSCP-to-DSCP-mutation map is applied to a specific port.

Table 1 Default CoS-to-DSCP Map
CoS Value	DSCP Value
0	0
1	8
2	16
3	24
4	32
5	40
6	48
7	56

Table 2 Default DSCP-to-CoS Map
DSCP Value	CoS Value
0–7	0
8–15	1
16–23	2
24–31	3
32–39	4
40–47	5
48–55	6
56–63	7

Table 3 Default IP-Precedence-to-DSCP Map
IP Precedence Value	DSCP Value
0	0
1	8
2	16
3	24
4	32
5	40
6	48
7	56

Examples

This example shows how to define the IP-precedence-to-DSCP map and to map IP-precedence values 0 to 7 to DSCP values of 0, 10, 20, 30, 40, 50, 55, and 60:

Switch# configure terminal
Switch(config)# mls qos map ip-prec-dscp 0 10 20 30 40 50 55 60

This example shows how to define the policed-DSCP map. DSCP values 1, 2, 3, 4, 5, and 6 are marked down to DSCP value 0. Marked DSCP values that not explicitly configured are not modified:

Switch# configure terminal
Switch(config)# mls qos map policed-dscp 1 2 3 4 5 6 to 0

This example shows how to define the DSCP-to-CoS map. DSCP values 20, 21, 22, 23, and 24 are mapped to CoS 1. DSCP values 10, 11, 12, 13, 14, 15, 16, and 17 are mapped to CoS 0:

Switch# configure terminal
Switch(config)# mls qos map dscp-cos 20 21 22 23 24 to 1
Switch(config)# mls qos map dscp-cos 10 11 12 13 14 15 16 17 to 0

This example shows how to define the CoS-to-DSCP map. CoS values 0 to 7 are mapped to DSCP values 0, 5, 10, 15, 20, 25, 30, and 35:

Switch# configure terminal
Switch(config)# mls qos map cos-dscp 0 5 10 15 20 25 30 35

This example shows how to define the DSCP-to-DSCP-mutation map. All the entries that are not explicitly configured are not modified (remain as specified in the null map):

Switch# configure terminal
Switch(config)# mls qos map dscp-mutation mutation1 1 2 3 4 5 6 7 to 10
Switch(config)# mls qos map dscp-mutation mutation1 8 9 10 11 12 13 to 10
Switch(config)# mls qos map dscp-mutation mutation1 20 21 22 to 20
Switch(config)# mls qos map dscp-mutation mutation1 0 31 32 33 34 to 30

You can verify your settings by entering the show mls qos maps privileged EXEC command.

Related Commands

Command	Description
mls qos dscp-mutation	Applies a DSCP-to-DSCP-mutation map to a DSCP-trusted port.
show mls qos maps	Displays quality of service (QoS) mapping information.

mls qos queue-set output buffers

To allocate buffers to a queue set of four egress queues per port, use the mls qos queue-set output buffers command in global configuration mode. To return to the default setting, use the no form of this command.

mls qos queue-set output qset-id buffers allocation1 ... allocation4

no mls qos queue-set output qset-id buffers

Syntax Description

qset-id

Queue set ID. Each port belongs to a queue set, which defines all the characteristics of the four egress queues per port. The range is 1 to 2.

allocation1 ... allocation4

Buffer space allocation (percentage) for each queue (four values for queues 1 to 4).

For allocation1, allocation3, and allocation4, the range is 0 to 99.

For allocation2, the range is 1 to 100 (including the CPU buffer). Separate each value with a space.

Command Default

All allocation values are equally mapped among the four queues (25, 25, 25, 25). Each queue has 1/4^th of the buffer space.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Specify the allocation values, and separate each with a space.

Allocate buffers according to the importance of the traffic. For example, give a large percentage of the buffer to the queue with the highest-priority traffic.

Note

The egress queue default settings are suitable for most situations. Change them only when you have a thorough understanding of the egress queues and if these settings do not meet your QoS solution.

To configure different classes of traffic with different characteristics, use this command with the mls qos queue-set output qset-id threshold global configuration command.

Examples

This example shows how to map a port to queue set 2. It allocates 40 percent of the buffer space to egress queue 1 and 20 percent to egress queues 2, 3, and 4.

Switch(config)# mls qos queue-set output 2 buffers 40 20 20 20 
Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# queue-set 2

You can verify your settings by entering the show mls qos interface [interface-id buffers] or the show mls qos queue-set privileged EXEC command.

Related Commands

Command	Description
mls qos queue-set output threshold	Configures the weighted tail-drop (WTD) thresholds, guarantees the availability of buffers, and configures the maximum memory allocation to a queue set.
queue-set	Maps a port to a queue set.
show mls qos interface	Displays quality of service (QoS) information at the port level
show mls qos queue-set	Displays egress queue settings for the queue set.

mls qos queue-set output threshold

To configure the weighted tail-drop (WTD) thresholds, to guarantee the availability of buffers, and to configure the maximum memory allocation to a queue set (four egress queues per port), use the mls qos queue-set output threshold command in global configuration mode. Use the no form of this command to return to the default setting.

mls qos queue-set output qset-id threshold [ queue-id ] drop-threshold1 drop-threshold2 reserved-threshold maximum-threshold

no mls qos queue-set output qset-id threshold [ queue-id ]

Syntax Description

qset-id	Queue set ID. Each port belongs to a queue set, which defines all the characteristics of the four egress queues per port. The range is 1 to 2.
queue-id	(Optional) The queue in the queue set on which the command is performed. The range is 1 to 4.
drop-threshold1 drop-threshold2	Two WTD thresholds expressed as a percentage of the allocated memory of the queue. The range is 1 to 3200 percent.
reserved-threshold	The amount of memory to be guaranteed (reserved) for the queue and expressed as a percentage of the allocated memory. The range is 1 to 100 percent.
maximum-threshold	Queue in the full condition that is enabled to get more buffers than are reserved for it. This is the maximum memory the queue can have before the packets are dropped. The range is 1 to 3200 percent.

Command Default

When quality of service (QoS) is enabled, WTD is enabled.

For default egress queue WTD threshold values , see Table 1.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Use the mls qos queue-set output qset-id buffers global configuration command to allocate a fixed number of buffers to the four queues in a queue set.

Table 4 Default Egress Queue WTD Threshold Settings
Feature	Queue 1	Queue 2	Queue 3	Queue 4
WTD drop threshold 1	100 percent	200 percent	100 percent	100 percent
WTD drop threshold 2	100 percent	200 percent	100 percent	100 percent
Reserved threshold	50 percent	100 percent	50 percent	50 percent
Maximum threshold	400 percent	400 percent	400 percent	400 percent

The drop-threshold percentages can exceed 100 percent and can be up to the maximum (if the maximum threshold exceeds 100 percent).

While buffer ranges allow individual queues in the queue set to use more of the common pool when available, the maximum user-configurable number of packets for each queue is still internally limited to 3200 percent, or 32 times the allocated number of buffers. One packet can use one 1 or more buffers.

Note

The egress queue default settings are suitable for most situations. Change them only when you have a thorough understanding of the egress queues and if these settings do not meet your QoS solution.

The switch uses a buffer allocation scheme to reserve a minimum amount of buffers for each egress queue, to prevent any queue or port from consuming all the buffers and depriving other queues, and to decide whether to grant buffer space to a requesting queue. The switch decides whether the target queue has not consumed more buffers than its reserved amount (under-limit), whether it has consumed all of its maximum buffers (over-limit), and whether the common pool is empty (no free buffers) or not empty (free buffers). If the queue is not over-limit, the switch can allocate buffer space from the reserved pool or from the common pool (if it is not empty). If there are no free buffers in the common pool or if the queue is over-limit, the switch drops the frame.

Examples

This example shows how to map a port to queue set 2. It configures the drop thresholds for queue 2 to 40 and 60 percent of the allocated memory, guarantees (reserves) 100 percent of the allocated memory, and configures 200 percent as the maximum memory this queue can have before packets are dropped:

Switch(config)# mls qos queue-set output 2 threshold 2 40 60 100 200
Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# queue-set 2

You can verify your settings by entering the show mls qos interface [interface-id] buffers or the show mls qos queue-set privileged EXEC command.

Related Commands

Command	Description
mls qos queue-set output buffers	Allocates buffers to a queue set.
queue-set	Maps a port to a queue set.
show mls qos interface	Displays quality of service (QoS) information at the port level.
show mls qos queue-set	Displays egress queue settings for the queue-set.

mls qos rewrite ip dscp

To configure the switch to change or rewrite the Differentiated Services Code Point (DSCP) field of an incoming IP packet, use the mls qos rewrite ip dscp command in global configuration mode. Use the no form of this command to configure the switch to not modify or rewrite the DSCP field of the packet and to enable DSCP transparency.

mls qos rewrite ip dscp

no mls qos rewrite ip dscp

Syntax Description

This command has no arguments or keywords.

Command Default

DSCP transparency is disabled. The switch changes the DSCP field of the incoming IP packet.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

DSCP transparency affects only the DSCP field of a packet at the egress. If DSCP transparency is enabled by using the no mls qos rewrite ip dscp command, the switch does not modify the DSCP field in the incoming packet, and the DSCP field in the outgoing packet is the same as that in the incoming packet.

Note

Enabling DSCP transparency does not affect the port trust settings on IEEE 802.1Q tunneling ports.

By default, DSCP transparency is disabled. The switch modifies the DSCP field in an incoming packet, and the DSCP field in the outgoing packet is based on the quality of service (QoS) configuration, including the port trust setting, policing and marking, and the DSCP-to-DSCP mutation map.

Regardless of the DSCP transparency configuration, the switch modifies the internal DSCP value of the packet that the switch uses to generate a class of service (CoS) value representing the priority of the traffic. The switch also uses the internal DSCP value to select an egress queue and threshold.

For example, if QoS is enabled and an incoming packet has a DSCP value of 32, the switch might modify the internal DSCP value based on the policy-map configuration and change the internal DSCP value to 16. If DSCP transparency is enabled, the outgoing DSCP value is 32 (same as the incoming value). If DSCP transparency is disabled, the outgoing DSCP value is 16 because it is based on the internal DSCP value.

Examples

This example shows how to enable DSCP transparency and configure the switch to not change the DSCP value of the incoming IP packet:

Switch(config)# mls qos
Switch(config)# no mls qos rewrite ip dscp

This example shows how to disable DSCP transparency and configure the switch to change the DSCP value of the incoming IP packet:

Switch(config)# mls qos
Switch(config)# mls qos rewrite ip dscp

You can verify your settings by entering the show running config include rewrite privileged EXEC command.

Related Commands

Command	Description
mls qos	Enables QoS globally.
show mls qos	Displays QoS information.
show running-config \| include rewrite	Displays the DSCP transparency setting.

mls qos srr-queue output cos-map

To map class of service (CoS) values to an egress queue or to map CoS values to a queue and to a threshold ID, use the mls qos srr-queue output cos-map command global configuration mode. Use the no form of this command to return to the default setting.

mls qos srr-queue output cos-map queue queue-id { cos1 ... cos8 | threshold threshold-id cos1 ... cos8 }

no mls qos srr-queue output cos-map

Syntax Description

queue queue-id

Specifies a queue number.

For queue-id, the range is 1 to 4.

cos1 ... cos8

CoS values that are mapped to an egress queue.

For cos1...cos8, enter up to eight values, and separate each value with a space. The range is 0 to 7.

threshold threshold-id cos1...cos8

Maps CoS values to a queue threshold ID.

For threshold-id, the range is 1 to 3.

For cos1...cos8, enter up to eight values, and separate each value with a space. The range is 0 to 7.

Command Default

For default CoS output queue thresholds values, see Table 1.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

The drop-threshold percentage for threshold 3 is predefined. It is set to the queue-full state.

Note

The egress queue default settings are suitable for most situations. Change them only when you have a thorough understanding of the egress queues and if these settings do not meet your quality of service (QoS) solution.

You can assign two weighted tail-drop (WTD) threshold percentages to an egress queue by using the mls qos queue-set output qset-id threshold global configuration command.

You can map each CoS value to a different queue and threshold combination, allowing the frame to follow different behavior.

Table 5 Default Cos Output Queue Threshold Map
CoS Value	0	1	2	3	4	5	6	7
Queue ID–Threshold ID	2–1	2–1	3–1	3–1	4–1	1–1	4–1	4–1

Examples

This example shows how to map a port to queue set 1. It maps CoS values 0 to 3 to egress queue 1 and to threshold ID 1. It configures the drop thresholds for queue 1 to 50 and 70 percent of the allocated memory, guarantees (reserves) 100 percent of the allocated memory, and configures 200 percent as the maximum memory that this queue can have before packets are dropped.

Switch(config)# mls qos srr-queue output cos-map queue 1 threshold 1 0 1 2 3
Switch(config)# mls qos queue-set output 1 threshold 1 50 70 100 200
Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# queue-set 1

You can verify your settings by entering the show mls qos maps, the show mls qos interface [interface-id] buffers, or the show mls qos queue-set privileged EXEC command.

Related Commands

Command	Description
mls qos queue-set output threshold	Configures the WTD thresholds, guarantees the availability of buffers, and configures the maximum memory allocation to a queue-set.
mls qos srr-queue output dscp-map	Maps Differentiated Services Code Point (DSCP) values to an egress queue or maps DSCP values to a queue and to a threshold ID.
queue-set	Maps a port to a queue set.

show mls qos interface	Displays quality of service (QoS) information at the port level
show mls qos maps	Displays QoS mapping information.
show mls qos queue-set	Displays egress queue settings for the queue-set.

mls qos srr-queue output dscp-map

To map Differentiated Services Code Point (DSCP) values to an egress queue or to map DSCP values to a queue and to a threshold ID, use the mls qos srr-queue output dscp-map command in global configuration mode. Use the no form of this command to return to the default setting.

mls qos srr-queue output dscp-map queue queue-id { dscp1 ... dscp8 | threshold threshold-id dscp1 ... dscp8 }

no mls qos srr-queue output dscp-map

Syntax Description

queue queue-id

Specifies a queue number.

For queue-id, the range is 1 to 4.

dscp1 ... dscp8

DSCP values that are mapped to an egress queue.

For dscp1...dscp8, enter up to eight values, and separate each value with a space. The range is 0 to 63.

threshold threshold-id dscp1...dscp8

Maps DSCP values to a queue threshold ID.

For threshold-id, the range is 1 to 3.

For dscp1...dscp8, enter up to eight values, and separate each value with a space. The range is 0 to 63.

Command Default

The default DSCP output queue thresholds are set.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

The drop-threshold percentage for threshold 3 is predefined. It is set to the queue-full state.

For default DSCP output queue-threshold map values, see Table 1.

Note

The egress queue default settings are suitable for most situations. Change them only when you have a thorough understanding of the egress queues and if these settings do not meet your QoS solution.

You can assign two weighted tail-drop (WTD) threshold percentages to an egress queue by using the mls qos queue-set output qset-id threshold global configuration command.

You can map each DSCP value to a different queue and threshold combination, allowing the frame to follow different behavior.

You can map up to eight DSCP values per command.

Table 6 Default DSCP Output Queue Threshold Map
DSCP Value	0-7	8-15	16-23	24-31	32-39	40-47	48-55	56-63
Queue ID–Threshold ID	2–1	2–1	3–1	3–1	4–1	1–1	4–1	4–1

Examples

This example shows how to map a port to queue set 1. It maps DSCP values 0 to 3 to egress queue 1 and to threshold ID 1. It configures the drop thresholds for queue 1 to 50 and 70 percent of the allocated memory, guarantees (reserves) 100 percent of the allocated memory, and configures 200 percent as the maximum memory that this queue can have before packets are dropped.

Switch(config)# mls qos srr-queue output dscp-map queue 1 threshold 1 0 1 2 3
Switch(config)# mls qos queue-set output 1 threshold 1 50 70 100 200
Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# queue-set 1

You can verify your settings by entering the show mls qos maps, the show mls qos interface [interface-id] buffers or the show mls qos queue-set privileged EXEC command.

Related Commands

Command	Description
mls qos srr-queue output cos-map	Maps class of service (CoS) values to an egress queue or maps CoS values to a queue and to a threshold ID.
mls qos queue-set output threshold	Configures the WTD thresholds, guarantees the availability of buffers, and configures the maximum memory allocation to a queue-set.
queue-set	Maps a port to a queue set.
show mls qos interface	Displays quality of service (QoS) information at the port level
show mls qos maps	Displays QoS mapping information.
show mls qos queue-set	Displays egress queue settings for the queue set.

mls qos trust

To configure the port trust state, use the mls qos trust command in interface configuration mode. Use the no form of this command to return a port to its untrusted state.

mls qos trust [ cos | device { cisco-phone | cts | ip-camera | media-player } | dscp | ip-precedence ]

no mls qos trust [ cos | device { cisco-phone | cts | ip-camera | media-player } | dscp | ip-precedence ]

Syntax Description

cos	(Optional) Classifies an ingress packet by using the packet CoS value. For an untagged packet, use the port default CoS value.
device cisco-phone	(Optional) Classifies an ingress packet by trusting the CoS or DSCP value sent from the Cisco IP Phone (trusted boundary), depending on the trust setting.
device {cts \| ip-camera \| media-player}	(Optional) Classifies an ingress packet by trusting the CoS or DSCP value for these video devices: cts—Cisco TelePresence System ip-camera—Cisco IP camera media-player—Cisco digital media player For an untagged packet, use the port default CoS value.
dscp	(Optional) Classifies an ingress packet by using the packet DSCP value (most significant 6 bits of 8-bit service-type field). For a non-IP packet, the packet CoS is used if the packet is tagged. For an untagged packet, the default port CoS value is used.
ip-precedence	(Optional) Classifies an ingress packet by using the packet IP-precedence value (most significant 3 bits of 8-bit service-type field). For a non-IP packet, the packet CoS is used if the packet is tagged. For an untagged packet, the port default CoS value is used.

Command Default

The port is not trusted. If no keyword is specified when you enter the command, the default is dscp.

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Packets entering a quality of service (QoS) domain are classified at the edge of the domain. When the packets are classified at the edge, the switch port within the QoS domain can be configured to one of the trusted states because there is no need to classify the packets at every switch within the domain. Use this command to specify whether the port is trusted and which fields of the packet to use to classify traffic.

When a port is configured with trust DSCP or trust IP precedence and the incoming packet is a non-IP packet, the CoS-to-DSCP map is used to derive the corresponding DSCP value from the CoS value. The CoS can be the packet CoS for trunk ports or the port default CoS for nontrunk ports.

If the DSCP is trusted, the DSCP field of the IP packet is not modified. However, it is still possible that the CoS value of the packet is modified (according to DSCP-to-CoS map).

If the CoS is trusted, the CoS field of the packet is not modified, but the DSCP can be modified (according to CoS-to-DSCP map) if the packet is an IP packet.

The trusted boundary feature prevents security problems if users disconnect their PCs from networked Cisco IP Phones and connect them to the switch port to take advantage of trusted CoS or DSCP settings. You must globally enable the Cisco Discovery Protocol (CDP) on the switch and on the port connected to the IP phone. If the telephone is not detected, trusted boundary disables the trusted setting on the switch or routed port and prevents misuse of a high-priority queue.

If you configure the trust setting for DSCP or IP precedence, the DSCP or IP precedence values in the incoming packets are trusted. If you configure the mls qos cos override interface configuration command on the switch port connected to the IP phone, the switch overrides the CoS of the incoming voice and data packets and assigns the default CoS value to them.

For an inter-QoS domain boundary, you can configure the port to the DSCP-trusted state and apply the DSCP-to-DSCP-mutation map if the DSCP values are different between the QoS domains.

Classification using a port trust state (for example, mls qos trust [cos | dscp | ip-precedence] and a policy map (for example, service-policy input policy-map-name) are mutually exclusive. The last one configured overwrites the previous configuration.

Related Commands

This example shows how to configure a port to trust the IP precedence field in the incoming packet:

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# mls qos trust ip-precedence

This example shows how to specify that the Cisco IP Phone connected on a port is a trusted device:

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# mls qos trust device cisco-phone

You can verify your settings by entering the show mls qos interface privileged EXEC command.

Related Commands

Command	Description
mls qos cos	Defines the default CoS value of a port or assigns the default CoS to all incoming packets on the port.
mls qos dscp-mutation	Applies a DSCP-to DSCP-mutation map to a DSCP-trusted port.
mls qos map	Defines the CoS-to-DSCP map, DSCP-to-CoS map, the DSCP-to-DSCP-mutation map, the IP-precedence-to-DSCP map, and the policed-DSCP map.
show mls qos interface	Displays QoS information.

police

To define a policer for classified traffic, use the police command in policy-map class configuration mode. Use the no form of this command to remove an existing policer.

police rate-bps burst-byte [ exceed-action [ drop | policed-dscp-transmit ] ]

no police rate-bps burst-byte [ exceed-action [ drop | policed-dscp-transmit ] ]

Syntax Description

rate-bps	Specifies the average traffic rate in bits per second (b/s). The range is 8000 to 10000000000.
burst-byte	Specifies the normal burst size in bytes. The range is 8000 to 1000000.
exceed-action drop	(Optional) Sets the traffic rate. If the rate is exceeded, the switch drops the packet .
exceed-action policed-dscp-transmit	(Optional) Sets the traffic rate. If the rate is exceeded, the switch changes the Differentiated Services Code Point (DSCP) of the packet to that specified in the policed-DSCP map and then sends the packet.
aggregate	Chooses the aggregate policer for the current class.

Command Default

No policers are defined.

Command Modes

Policy-map class configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

A policer defines a maximum permissible rate of transmission, a maximum burst size for transmissions, and an action to take if either maximum is exceeded.

The port ASIC device, which controls more than one physical port, supports 256 policers on the switch (255 user-configurable policers plus 1 policer reserved for internal use). The maximum number of configurable policers supported per port is 63. Policers are allocated on demand by the software and are constrained by the hardware and ASIC boundaries. You cannot reserve policers per port. There is no guarantee that a port will be assigned to any policer.

To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.

Policing uses a token-bucket algorithm. You configure the bucket depth (the maximum burst that is tolerated before the bucket overflows) by using the burst-byte option of the police policy-map class configuration command or the mls qos aggregate-policer global configuration command. You configure how quickly (the average rate) the tokens are removed from the bucket by using the rate-bps option of the police policy-map class configuration command or the mls qos aggregate-policer global configuration command. For more information, see the software configuration guide for this release.

Examples

This example shows how to configure a policer that drops packets if traffic exceeds 1 Mb/s average rate with a burst size of 20 KB. The DSCPs of incoming packets are trusted, and there is no packet modification.

Switch(config)# policy-map policy1
Switch(config-pmap)# class class1
Switch(config-pmap-c)# trust dscp
Switch(config-pmap-c)# police 1000000 20000 exceed-action drop
Switch(config-pmap-c)# exit

This example shows how to configure a policer, which marks down the DSCP values with the values defined in policed-DSCP map and sends the packet:

Switch(config)# policy-map policy2
Switch(config-pmap)# class class2
Switch(config-pmap-c)# police 1000000 20000 exceed-action policed-dscp-transmit
Switch(config-pmap-c)# exit

You can verify your settings by entering the show policy-map privileged EXEC command.

Related Commands

Command	Description
class	Defines a traffic classification match criteria (through the police, set, and trust policy-map class configuration commands) for the specified class-map name.
class-map	Create a class map to be used for matching packets to the class whose name you specify with the class command.
mls qos map policed-dscp	Applies a policed-DSCP map to a DSCP-trusted port.
policy map	Creates or modifies a policy map that can be attached to multiple ports to specify a service policy.
set	Classifies IP traffic by setting a DSCP or IP-precedence value in the packet.
show policy-map	Displays QoS policy maps.
trust	Defines a trust state for traffic classified through the class policy-map configuration or the class-map global configuration command.

police aggregate

To apply an aggregate policer to multiple classes in the same policy map, use the police aggregate command in policy-map class configuration mode. Use the no form of this command to remove the specified policer.

police aggregate aggregate-policer-name

no police aggregate aggregate-policer-name

Syntax Description

aggregate-policer-name

The name of the aggregate policer.

Command Default

No aggregate policers are defined.

Command Modes

Policy-map class configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

A policer defines a maximum permissible rate of transmission, a maximum burst size for transmissions, and an action to take if either maximum is exceeded.

The port ASIC device, which controls more than one physical port, supports 256 policers on the switch (255 user-configurable policers plus 1 policer reserved for internal use). The maximum number of configurable policers supported per port is 63. Policers are allocated on demand by the software and are constrained by the hardware and ASIC boundaries. You cannot reserve policers per port. There is no guarantee that a port will be assigned to any policer.

You set aggregate policer parameters by using the mls qos aggregate-policer global configuration command. You apply an aggregate policer to multiple classes in the same policy map; you cannot use an aggregate policer across different policy maps.

To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.

You cannot configure aggregate policers in hierarchical policy maps.

Examples

This example shows how to define the aggregate policer parameters and to apply the policer to multiple classes in a policy map:

Switch(config)# mls qos aggregate-policer agg_policer1 10000 1000000 exceed-action drop
Switch(config)# policy-map policy2
Switch(config-pmap)# class class1
Switch(config-pmap-c)# police aggregate agg_policer1
Switch(config-pmap-c)# exit
Switch(config-pmap)# class class2
Switch(config-pmap-c)# set dscp 10
Switch(config-pmap-c)# police aggregate agg_policer1
Switch(config-pmap-c)# exit
Switch(config-pmap)# class class3
Switch(config-pmap-c)# trust dscp
Switch(config-pmap-c)# police aggregate agg_policer2
Switch(config-pmap-c)# exit

You can verify your settings by entering the show mls qos aggregate-policer privileged EXEC command.

Related Commands

Command	Description
mls qos aggregate-policer	Defines policer parameters, which can be shared by multiple classes within a policy map.
show mls qos aggregate-policer	Displays the quality of service (QoS) aggregate policer configuration.

policy map

To create or modify a policy map that can be attached to multiple physical ports and to enter policy-map configuration mode, use the policy-map command in global configuration mode. Use the no form of this command to delete an existing policy map and to return to global configuration mode.

policy-map policy-map-name

no policy-map policy-map-name

Syntax Description

policy-map-name

The name of the policy map.

Command Default

No policy maps are defined.

The default behavior is to set the Differentiated Services Code Point (DSCP) to 0 if the packet is an IP packet and to set the class of service (CoS) to 0 if the packet is tagged. No policing is performed.

Command Modes

Global configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

After entering the policy-map command, you enter policy-map configuration mode, and these configuration commands are available:

class—Defines the classification match criteria for the specified class map.
description—Describes the policy map (up to 200 characters).
exit—Exits policy-map configuration mode and returns you to global configuration mode.
no—Removes a previously defined policy map.

To return to global configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.

Before configuring policies for classes whose match criteria are defined in a class map, use the policy-map command to specify the name of the policy map to be created, added to, or modified. Entering the policy-map command also enables the policy-map configuration mode in which you can configure or modify the class policies for that policy map.

You can configure class policies in a policy map only if the classes have match criteria defined for them. To configure the match criteria for a class, use the class-map global configuration and match class-map configuration commands. You define packet classification on a physical-port basis.

You can configure QoS only on physical ports. Configure the QoS settings, such as classification, queueing, and scheduling, and apply the policy map to a port. When configuring QoS on a physical port, you apply a nonhierarchical policy map to a port. A nonhierarchical policy map is the same as the port-based policy maps in the switch.

Examples

This example shows how to create a policy map called policy1.

Switch(config)# policy-map policy1

This example shows how to delete policymap2:

Switch(config)# no policy-map policymap2

You can verify your settings by entering the show policy-map privileged EXEC command.

Related Commands

Command	Description
class	Defines a traffic classification match criteria (through the police, set, and trust policy-map class configuration command) for the specified class-map name.
class-map	Creates a class map to be used for matching packets to the class whose name you specify.
service-policy	Applies a policy map to a physical port.
show policy-map	Displays QoS policy maps.

queue-set

To map a port to a queue set, use the queue-set command in interface configuration mode. Use the no form of this command to return to the default setting.

queue-set qset-id

no queue-set qset-id

Syntax Description

qset-id

Queue-set ID. Each port belongs to a queue set, which defines all the characteristics of the four egress queues per port. The range is 1 to 2.

Command Default

The queue set ID is 1.

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

For information about automatic generation of the queue-set ID with the auto qos voip command, see the “Usage Guidelines” section for the auto qos voip command.

Examples

This example shows how to map a port to queue-set 2:

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# queue-set 2

You can verify your settings by entering the show mls qos interface [interface-id] buffers privileged EXEC command.

Related Commands

Command	Description
mls qos queue-set output buffers	Allocates buffers to a queue set.
mls qos queue-set output threshold	Configures the weighted tail-drop (WTD) thresholds, guarantees the availability of buffers, and configures the maximum memory allocation to a queue set.
show mls qos interface	Displays quality of service (QoS) information.

service-policy

To apply a policy map to the input of a physical port, use the service-policy command in interface configuration mode. Use the no form of this command to remove the policy map and port association.

service-policy { input | output} policy-map-name

no service-policy { input | output} policy-map-name

Syntax Description

input policy-map-name

Applies the specified policy map to the input of a physical port.

Command Default

No policy maps are attached to the port.

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Though visible in the command-line help strings, the output keyword is not supported.

Policy maps can be configured on physical ports. A policy map is defined by the policy map command.

Only one policy map is supported per port, per direction. In other words, only one input policy and one output policy is allowed on any one port.

You can apply a policy map to incoming traffic on a physical port. .

Classification using a port trust state (for example, mls qos trust [cos | dscp | ip-precedence] and a policy map (for example, service-policy input policy-map-name) are mutually exclusive. The last one configured overwrites the previous configuration.

Examples

This example shows how to remove plcmap2 from a physical port:

Switch(config)# interface gigabitethernet2/0/2
Switch(config-if)# no service-policy input plcmap2

You can verify your settings by entering the show running-config privileged EXEC command.

Related Commands

Command	Description
policy map	Creates or modifies a policy map that can be attached to multiple ports to specify a service policy.
show policy-map	Displays QoS policy maps.
show running-config	Displays the operating configuration.

set

To classify IP traffic by setting a Differentiated Services Code Point (DSCP) or an IP-precedence value in the packet, use the set command in policy-map class configuration mode. Use the no form of this command to remove traffic classification.

set { dscp new-dscp | ip { dscp | precedence } | precedence precedence }

no set { dscp new-dscp | ip { dscp | precedence } | precedence precedence }

Syntax Description

dscp new-dscp

Sets the DSCP value in IPv4 and IPv6 packets.

The range is 0 to 63.

ip {dscp | precedence }

Sets the IP values.

dscp—Sets the IP DSCP value.
precedence—Sets the IP precedence value.

precedence new-precedence

Sets the precedence in IPv4 and IPv6 packets.

The range is 0 to 7.

Command Default

No traffic classification is defined.

Command Modes

Policy-map class configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

If you have used the set ip dscp policy-map class configuration command, the switch changes this command to set dscp in the switch configuration. If you enter the set ip dscp policy-map class configuration command, this setting appears as set dscp in the switch configuration.

You can use the set ip precedence policy-map class configuration command or the set precedence policy-map class configuration command. This setting appears as set ip precedence in the switch configuration.

The set command is mutually exclusive with the trust policy-map class configuration command within the same policy map.

For the set dscp new-dscp or the set ip precedence new-precedence command, you can enter a mnemonic name for a commonly used value. For example, you can enter the set dscp af11 command, which is the same as entering the set dscp 10 command. You can enter the set ip precedence critical command, which is the same as entering the set ip precedence 5 command. For a list of supported mnemonics, enter the set dscp ? or the set ip precedence ? command to see the command-line help strings.

To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.

Examples

This example shows how to assign DSCP 10 to all FTP traffic without any policers:

Switch(config)# policy-map policy_ftp
Switch(config-pmap)# class-map ftp_class
Switch(config-cmap)# exit
Switch(config)# policy-map policy_ftp
Switch(config-pmap)# class ftp_class
Switch(config-pmap-c)# set dscp 10
Switch(config-pmap)# exit

You can verify your settings by entering the show policy-map privileged EXEC command.

Related Commands

Command	Description
class	Defines a traffic classification match criteria (through the police, set, and trust policy-map class configuration commands) for the specified class-map name.
police	Defines a policer for classified traffic.
policy map	Creates or modifies a policy map that can be attached to multiple ports to specify a service policy.
police	Defines a policer for classified traffic.
policy-map	Creates or modifies a policy map that can be attached to multiple ports to specify a service policy.
show policy-map	Displays QoS policy maps.
trust	Defines a trust state for traffic classified through the class policy-map configuration command or the class-map global configuration command.

show class-map

To display quality of service (QoS) class maps, which define the match criteria to classify traffic, use the show class-map command in EXEC mode.

show class-map [ class-map-name | type control subscriber {all | class-map-name}]

Syntax Description

class-map-name	(Optional) Class map name.
type control subscriber	(Optional) Displays information about control class maps.
all	(Optional) Displays information about all control class maps.

Command Modes

User EXEC

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

This command is supported only on the LAN Base image.

Examples

This is an example of output from the show class-map command:

Switch# show class-map
 Class Map match-any videowizard_10-10-10-10 (id 2)
   Match access-group name videowizard_10-10-10-10

 Class Map match-any class-default (id 0)
   Match any
 Class Map match-any dscp5 (id 3)
   Match ip dscp 5

Related Commands

Command	Description
class-map	Creates a class map to be used for matching packets to the class whose name you specify.
match (class-map configuration)	Defines the match criteria to classify traffic.

show mls qos

To display global quality of service (QoS) configuration information, use the show mls qos command in EXEC mode.

show mls qos

Syntax Description

This command has no arguments or keywords.

Command Modes

User EXEC

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Examples

This is an example of output from the show mls qos command when QoS is enabled and Differentiated Services Code Point (DSCP) transparency is disabled:

Switch# show mls qos
QoS is enabled
QoS ip packet dscp rewrite is disabled

This is an example of output from the show mls qos command when QoS is enabled and DSCP transparency is enabled:

Switch# show mls qos
QoS is enabled
QoS ip packet dscp rewrite is enabled

Related Commands

Command	Description
mls qos	Enables QoS on the entire switch.

show mls qos aggregate-policer

To display the quality of service (QoS) aggregate policer configuration, use the show mls qos aggregate-policer command in EXEC mode.

show mls qos aggregate-policer [ aggregate-policer-name]

Syntax Description

aggregate-policer-name

(Optional) Displays the policer configuration for the specified name.

Command Modes

User EXEC

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

A policer defines a maximum permissible rate of transmission, a maximum burst size for transmissions, and an action to take if either maximum is exceeded.

This command is supported only on the LAN Base image.

Examples

This is an example of output from the show mls qos aggregate-policer command:


Switch# show mls qos aggregate-policer policer1

aggregate-policer policer1 1000000 2000000 exceed-action drop
Not used by any policy map

Related Commands

Command	Description
mls qos aggregate-policer	Defines policer parameters that can be shared by multiple classes within a policy map.

show mls qos interface

To display quality of service (QoS) information at the port level, use the show mls qos interface command in EXEC mode.

show mls qos interface [ interface-id] [ buffers | queueing | statistics ]

Syntax Description

interface-id	(Optional) The QoS information for the specified port. Valid interfaces include physical ports.
buffers	(Optional) Displays the buffer allocation among the queues.
queueing	(Optional) Displays the queueing strategy (shared or shaped) and the weights corresponding to the queues.
statistics	(Optional) Displays statistics for sent and received Differentiated Services Code Points (DSCPs) and class of service (CoS) values, the number of packets enqueued or dropped per egress queue, and the number of in-profile and out-of-profile packets for each policer.

Command Modes

User EXEC

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Though visible in the command-line help string, the policers keyword is not supported.

This command is supported only on the LAN Base image.

Examples

This is an example of output from the show mls qos interface interface-id command when port-based QoS is enabled:

Switch# show mls qos interface gigabitethernet1/0/1
GigabitEthernet1/0/1
trust state: trust cos
trust mode: trust cos
trust enabled flag: ena
COS override: dis
default COS: 0
DSCP Mutation Map: Default DSCP Mutation Map
Trust device: none
qos mode: port-based

This is an example of output from the show mls qos interface interface-id command when port-based QoS is disabled:

Switch# show mls qos interface  gigabitethernet1/0/1
GigabitEthernet1/0/1
QoS is disabled. When QoS is enabled, following settings will be applied
trust state: trust cos
trust mode: trust cos
trust enabled flag: ena
COS override: dis
default COS: 0
DSCP Mutation Map: Default DSCP Mutation Map
Trust device: none
qos mode: port-based

This is an example of output from the show mls qos interface interface-id buffers command:

Switch# show mls qos interface gigabitethernet1/0/2 buffers
GigabitEthernet1/0/2
The port is mapped to qset : 1
The allocations between the queues are : 25 25 25 25

This is an example of output from the show mls qos interface interface-id queueing command. The egress expedite queue overrides the configured shaped round robin (SRR) weights.

Switch# show mls qos interface gigabitethernet1/0/2 queueing
GigabitEthernet1/0/2
Egress Priority Queue :enabled
Shaped queue weights (absolute) :  25 0 0 0
Shared queue weights  :  25 25 25 25
The port bandwidth limit : 100  (Operational Bandwidth:100.0)
The port is mapped to qset : 1

This is an example of output from the show mls qos interface interface-id statistics command:

Switch# show mls qos interface gigabitethernet1/0/1 statistics
GigabitEthernet1/0/1 (All statistics are in packets)

  dscp: incoming
-------------------------------

  0 -  4 :       15233            0            0            0            0
  5 -  9 :           0            0            0            0            0
 10 - 14 :           0            0            0            0            0
 15 - 19 :           0            0            0            0            0
 20 - 24 :           0            0            0            0            0
 25 - 29 :           0            0            0            0            0
 30 - 34 :           0            0            0            0            0
 35 - 39 :           0            0            0            0            0
 40 - 44 :           0            0            0            0            0
 45 - 49 :           0            0            0       406417            0
 50 - 54 :           0            0            0            0            0
 55 - 59 :           0            0            0            0            0
 60 - 64 :           0            0            0            0
  dscp: outgoing
-------------------------------

  0 -  4 :         337            0            0            0            0
  5 -  9 :           0            0            0            0            0
 10 - 14 :           0            0            0            0            0
 15 - 19 :           0            0            0            0            0
 20 - 24 :           0            0            0            0            0
 25 - 29 :           0            0            0            0            0
 30 - 34 :           0            0            0            0            0
 35 - 39 :           0            0            0            0            0
 40 - 44 :           0            0            0            0            0
 45 - 49 :           0            0            0        13866            0
 50 - 54 :           0            0            0            0            0
 55 - 59 :           0            0            0            0            0
 60 - 64 :           0            0            0            0
  cos: incoming
-------------------------------

  0 -  4 :     1426270            0            0            0            0
  5 -  7 :           0            0            0
  cos: outgoing
-------------------------------

  0 -  4 :      131687           12            0            0         7478
  5 -  7 :        1993        25483       275213
  output queues enqueued:
 queue:    threshold1   threshold2   threshold3
-----------------------------------------------
 queue 0:           0           0           0
 queue 1:           0         341      441525
 queue 2:           0           0           0
 queue 3:           0           0           0

  output queues dropped:
 queue:    threshold1   threshold2   threshold3
-----------------------------------------------
 queue 0:           0           0           0
 queue 1:           0           0           0
 queue 2:           0           0           0
 queue 3:           0           0           0

Policer: Inprofile:            0 OutofProfile:            0

This table describes the fields in this display.

Table 7 show mls qos interface statistics Field Descriptions
Field		Description
DSCP	incoming	Number of packets received for each DSCP value.
DSCP	outgoing	Number of packets sent for each DSCP value.
CoS	incoming	Number of packets received for each CoS value.
CoS	outgoing	Number of packets sent for each CoS value.
Output queues	enqueued	Number of packets in the egress queue.
Output queues	dropped	Number of packets in the egress queue that are dropped.
Policer	Inprofile	Number of in-profile packets for each policer.
Policer	Outofprofile	Number of out-of-profile packets for each policer.

Related Commands

Command	Description
mls qos queue-set output buffers	Allocates buffers to a queue set.
mls qos queue-set output threshold	Configures the weighted tail-drop (WTD) thresholds, guarantees the availability of buffers, and configures the maximum memory allocation to a queue set.
mls qos srr-queue output cos-map	Maps CoS values to an egress queue or maps CoS values to a queue and to a threshold ID.
mls qos srr-queue output dscp-map	Maps DSCP values to an egress queue or maps DSCP values to a queue and to a threshold ID.
policy map	Creates or modifies a policy map.
priority-queue	Enables the egress expedite queue on a port.
queue-set	Maps a port to a queue set.
srr-queue bandwidth limit	Limits the maximum output on a port.
srr-queue bandwidth shape	Assigns the shaped weights and enables bandwidth shaping on the four egress queues mapped to a port.
srr-queue bandwidth share	Assigns the shared weights and enables bandwidth sharing on the four egress queues mapped to a port.

show mls qos maps

To display quality of service (QoS) mapping information, use the show mls qos maps command in EXEC mode.

Syntax Description

cos-dscp	(Optional) Displays class of service (CoS)-to-DSCP map.
cos-output-q	(Optional) Displays the CoS output queue threshold map.
dscp-cos	(Optional) Displays DSCP-to-CoS map.
dscp-mutation dscp-mutation-name	(Optional) Displays the specified DSCP-to-DSCP-mutation map.
dscp-output-q	(Optional) Displays the DSCP output queue threshold map.
ip-prec-dscp	(Optional) Displays the IP-precedence-to-DSCP map.
policed-dscp	(Optional) Displays the policed-DSCP map.

Command Default

None

Command Modes

User EXEC

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

During classification, QoS uses the mapping tables to represent the priority of the traffic and to derive a corresponding class of service (CoS) or Differentiated Services Code Point (DSCP) value from the received CoS, DSCP, or IP precedence value.

The policed-DSCP, DSCP-to-CoS, and the DSCP-to-DSCP-mutation maps appear as a matrix. The d1 column specifies the most-significant digit in the DSCP. The d2 row specifies the least-significant digit in the DSCP. The intersection of the d1 and d2 values provides the policed-DSCP, the CoS, or the mutated-DSCP value. For example, in the DSCP-to-CoS map, a DSCP value of 43 corresponds to a CoS value of 5.

The DSCP output queue threshold maps appear as a matrix. The d1 column specifies the most-significant digit of the DSCP number. The d2 row specifies the least-significant digit in the DSCP number. The intersection of the d1 and the d2 values provides the queue ID and threshold ID. For example, in the DSCP output queue threshold map, a DSCP value of 43 corresponds to queue 1 and threshold 3 (01-03).

The CoS output queue threshold maps show the CoS value in the top row and the corresponding queue ID and threshold ID in the second row. For example, in the CoS output queue threshold map, a CoS value of 5 corresponds to queue 1 and threshold 3 (1-3).

Examples

This is an example of output from the show mls qos maps command:

Switch# show mls qos maps
   Policed-dscp map:
     d1 :  d2 0  1  2  3  4  5  6  7  8  9
     ---------------------------------------
      0 :    00 01 02 03 04 05 06 07 08 09
      1 :    10 11 12 13 14 15 16 17 18 19
      2 :    20 21 22 23 24 25 26 27 28 29
      3 :    30 31 32 33 34 35 36 37 38 39
      4 :    40 41 42 43 44 45 46 47 48 49
      5 :    50 51 52 53 54 55 56 57 58 59
      6 :    60 61 62 63

   Dscp-cos map:
     d1 :  d2 0  1  2  3  4  5  6  7  8  9
     ---------------------------------------
      0 :    00 00 00 00 00 00 00 00 01 01
      1 :    01 01 01 01 01 01 02 02 02 02
      2 :    02 02 02 02 03 03 03 03 03 03
      3 :    03 03 04 04 04 04 04 04 04 04
      4 :    05 05 05 05 05 05 05 05 06 06
      5 :    06 06 06 06 06 06 07 07 07 07
      6 :    07 07 07 07

   Cos-dscp map:
        cos:   0  1  2  3  4  5  6  7
     --------------------------------
       dscp:   0  8 16 24 32 46 48 56

   IpPrecedence-dscp map:
     ipprec:   0  1  2  3  4  5  6  7
     --------------------------------
       dscp:   0  8 16 24 32 40 48 56

   Dscp-outputq-threshold map:
     d1 :d2    0     1     2     3     4     5     6     7     8     9
     ------------------------------------------------------------
      0 :    03-03 03-03 03-03 03-03 03-03 03-03 03-03 03-03 04-01 04-01
      1 :    04-02 04-01 04-02 04-01 04-02 04-01 02-01 02-01 02-01 02-01
      2 :    02-01 02-01 02-01 02-01 02-02 03-01 02-01 02-01 02-01 02-01
      3 :    02-01 02-01 01-03 01-03 02-01 02-01 02-01 02-01 02-01 02-01
      4 :    01-03 01-03 01-03 01-03 01-03 01-03 01-03 01-03 02-03 02-03
      5 :    02-03 02-03 02-03 02-03 02-03 02-03 02-03 02-03 02-03 02-03
      6 :    02-03 02-03 02-03 02-03

   Cos-outputq-threshold map:
              cos:  0   1   2   3   4   5   6   7
              ------------------------------------
  queue-threshold: 3-3 4-3 2-1 2-2 1-3 1-3 2-3 2-3


   Dscp-dscp mutation map:
   Default DSCP Mutation Map:
     d1 :  d2 0  1  2  3  4  5  6  7  8  9
     ---------------------------------------
      0 :    00 01 02 03 04 05 06 07 08 09
      1 :    10 11 12 13 14 15 16 17 18 19
      2 :    20 21 22 23 24 25 26 27 28 29
      3 :    30 31 32 33 34 35 36 37 38 39
      4 :    40 41 42 43 44 45 46 47 48 49
      5 :    50 51 52 53 54 55 56 57 58 59
      6 :    60 61 62 63

Related Commands

Command	Description
mls qos map	Defines the CoS-to-DSCP map, DSCP-to-CoS map, DSCP-to-DSCP-mutation map, IP-precedence-to-DSCP map, and the policed-DSCP map.
mls qos srr-queue output cos-map	Maps CoS values to an egress queue or maps CoS values to a queue and to a threshold ID.
mls qos srr-queue output dscp-map	Maps DSCP values to an egress queue or maps DSCP values to a queue and to a threshold ID.

show mls qos queue-set

To display quality of service (QoS) settings for the egress queues, use the show mls qos queue-set command in EXEC mode.

show mls qos queue-set [ gset-id]

Syntax Description

qset-id

(Optional) Queue set ID. Each port belongs to a queue set, which defines all the characteristics of the four egress queues per port. The range is 1 to 2.

Command Modes

User EXEC

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Examples

This is an example of output from the show mls qos queue-set command:

Switch# show mls qos queue-set
Queueset: 1
Queue   :        1       2       3       4
----------------------------------------------
buffers   :      25      25      25      25
threshold1:      100     200     100     100
threshold2:      100     200     100     100
reserved  :      50      50      50      50
maximum   :      400     400     400     400
Queueset: 2
Queue   :        1       2       3       4
----------------------------------------------
buffers   :      25      25      25      25
threshold1:      100     200     100     100
threshold2:      100     200     100     100
reserved  :      50      50      50      50
maximum   :      400     400     400     400

Related Commands

Command	Description
mls qos queue-set output buffers	Allocates buffers to the queue set.
mls qos queue-set output threshold	Configures the WTD thresholds, guarantees the availability of buffers, and configures the maximum memory allocation of the queue set.

show policy-map

To display quality of service (QoS) policy maps, which define classification criteria for incoming traffic, use the show policy-map command in EXEC mode.

show policy-map [ policy-map-name ]

Syntax Description

policy-map-name

(Optional) The policy map name.

Command Modes

User EXEC

Privileged EXEC

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Policy maps can include policers that specify the bandwidth limitations and the action to take if the limits are exceeded.

Note

Though visible in the command-line help string, the session,type,control-plane, and interface keywords are not supported; statistics shown in the display should be ignored.

Examples

This is an example of output from the show policy-map command:

Switch# show policy-map
Policy Map videowizard_policy2
  class  videowizard_10-10-10-10
   set dscp 34
   police 100000000 2000000 exceed-action drop

 Policy Map mypolicy
  class  dscp5
   set dscp 6

Related Commands

Command	Description
policy map	Creates or modifies a policy map that can be attached to multiple ports to specify a service policy.

srr-queue bandwidth limit

To limit the maximum output on a port, use the srr-queue bandwidth limit command in interface configuration mode. Use the no form of this command to return to the default setting.

srr-queue bandwidth limit weight1

no srr-queue bandwidth limit

Syntax Description

weight1

The port speed limit in percentage terms. The range is 10 to 90.

Command Default

The port is not rate limited and is set to 100 percent.

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

If you configure this command to 80 percent, the port is idle 20 percent of the time. The line rate drops to 80 percent of the connected speed. These values are not exact because the hardware adjusts the line rate in increments of six.

Examples

This example shows how to limit a port to 800 Mb/s:

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# srr-queue bandwidth limit 80

You can verify your settings by entering the show mls qos interface [interface-id] queueing privileged EXEC command.

Related Commands

Command	Description
mls qos queue-set output buffers	Allocates buffers to the queue set.
mls qos srr-queue input cos-map	Maps CoS values to egress queue or maps CoS values to a queue and to a threshold ID.
mls qos srr-queue output dscp-map	Maps DSCP values to an egress queue or maps DSCP values to a queue and to a threshold ID.
mls qos queue-set output threshold	Configures the WTD thresholds, guarantees the availability of buffers, and configures the maximum memory allocation for the queue set.
queue-set	Maps a port to a queue set.
show mls qos interface	Displays QoS information.
srr-queue bandwidth shape	Assigns the shaped weights and enables bandwidth shaping on the four egress queues mapped to a port.
srr-queue bandwidth share	Assigns the shared weights and enables bandwidth sharing on the four egress queues mapped to a port.

srr-queue bandwidth shape

To assign the shaped weights and to enable bandwidth shaping on the four egress queues mapped to a port, use the srr-queue bandwidth shape command in interface configuration mode. Use the no form of this command to return to the default setting.

srr-queue bandwidth shape weight1 weight2 weight3 weight4

no srr-queue bandwidth shape

Syntax Description

weight1 weight2 weight3 weight4

The weights that specify the percentage of the port that is shaped. The inverse ratio (1/weight) specifies the shaping bandwidth for this queue. Separate each value with a space. The range is 0 to 65535.

Command Default

Weight1 is set to 25; weight2, weight3, and weight4 are set to 0, and these queues are in shared mode.

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

In shaped mode, the queues are guaranteed a percentage of the bandwidth, and they are rate-limited to that amount. Shaped traffic does not use more than the allocated bandwidth even if the link is idle. Use shaping to smooth bursty traffic or to provide a smoother output over time.

The shaped mode overrides the shared mode.

If you configure a shaped queue weight to 0 by using the srr-queue bandwidth shape interface configuration command, this queue participates in shared mode. The weight specified with the srr-queue bandwidth shape command is ignored, and the weights specified with the srr-queue bandwidth share interface configuration command for a queue come into effect.

When configuring queues for the same port for both shaping and sharing, make sure that you configure the lowest numbered queue for shaping.

Note

The egress queue default settings are suitable for most situations. You should change them only when you have a thorough understanding of the egress queues and if these settings do not meet your QoS solution.

Examples

This example shows how to configure the queues for the same port for both shaping and sharing. Queues 2, 3, and 4 operate in the shared mode, because the weight ratios for these queues are set to 0. The bandwidth weight for queue 1 is 1/8, which is 12.5 percent. Queue 1 is guaranteed this bandwidth and limited to it; it does not extend its slot to the other queues even if the other queues have no traffic and are idle. Queues 2, 3, and 4 are in shared mode, and the setting for queue 1 is ignored. The bandwidth ratio allocated for the queues in shared mode is 4/(4+4+4), which is 33 percent:

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# srr-queue bandwidth shape 8 0 0 0
Switch(config-if)# srr-queue bandwidth share 4 4 4 4

You can verify your settings by entering the show mls qos interface [interface-id] queueing privileged EXEC command.

Related Commands

Command	Description
mls qos queue-set output buffers	Allocates buffers to a queue set.
mls qos srr-queue input cos-map	Maps CoS values to an egress queue or maps CoS values to a queue and to a threshold ID.
mls qos srr-queue output dscp-map	Maps DSCP values to an egress queue or maps DSCP values to a queue and to a threshold ID.
mls qos queue-set output threshold	Configures the WTD thresholds, guarantees the availability of buffers, and configures the maximum memory allocation to a queue set.
priority-queue	Enables the egress expedite queue on a port.
queue-set	Maps a port to a queue set.
show mls qos interface	Displays QoS information.
srr-queue bandwidth share	Assigns the shared weights and enables bandwidth sharing on the four egress queues mapped to a port.

srr-queue bandwidth share

To assign the shared weights and to enable bandwidth sharing on the four egress queues mapped to a port, use the srr-queue bandwidth share command in interface configuration mode. Use the no form of this command to return to the default setting.

srr-queue bandwidth share weight1 weight2 weight3 weight4

no srr-queue bandwidth share

Syntax Description

weight1 weight2 weight3 weight4

The ratios of weight1, weight2, weight3, and weight4 specify the ratio of the frequency in which the SRR scheduler dequeues packets. Separate each value with a space. The range is 1 to 255.

Command Default

Equal bandwidth is allocated to each queue (Equal bandwidth for weight1, weight2, weight3, and weight4).

Command Modes

Interface configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

The ratio of the weights is the ratio of frequency in which the shaped round-robin (SRR) scheduler dequeues packets from each queue.

The absolute value of each weight is meaningless, and only the ratio of parameters is used.

In shared mode, the queues share the bandwidth among them according to the configured weights. The bandwidth is guaranteed at this level but not limited to it. For example, if a queue empties and does not require a share of the link, the remaining queues can expand into the unused bandwidth and share it among themselves.

If you configure a shaped queue weight to 0 by using the srr-queue bandwidth shape interface configuration command, this queue participates in SRR shared mode. The weight specified with the srr-queue bandwidth shape command is ignored, and the weights specified with the srr-queue bandwidth share interface configuration command for a queue take effect.

When configuring queues for the same port for both shaping and sharing, make sure that you configure the lowest numbered queue for shaping.

Note

The egress queue default settings are suitable for most situations. Change them only when you have a thorough understanding of the egress queues and if these settings do not meet your QoS solution.

Examples

This example shows how to configure the weight ratio of the SRR scheduler running on an egress port. Four queues are used. The bandwidth ratio allocated for each queue in shared mode is 1/(1+2+3+4), 2/(1+2+3+4), 3/(1+2+3+4), and 4/(1+2+3+4), which is 10 percent, 20 percent, 30 percent, and 40 percent for queues 1, 2, 3, and 4. This means that queue 4 has four times the bandwidth of queue 1, twice the bandwidth of queue 2, and one-and-a-third times the bandwidth of queue 3.

Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# srr-queue bandwidth share 1 2 3 4

You can verify your settings by entering the show mls qos interface [interface-id queueing] privileged EXEC command.

Related Commands

Command	Description
mls qos queue-set output buffers	Allocates buffers to a queue set.
mls qos queue-set output threshold	Configures the weighted tail-drop (WTD) thresholds, guarantees the availability of buffers, and configures the maximum memory allocation to a queue set.
mls qos srr-queue input cos-map	Maps class of service (CoS) values to an egress queue or maps CoS values to a queue and to a threshold ID.
mls qos srr-queue output dscp-map	Maps Differentiated Services Code Point (DSCP) values to an egress queue or maps DSCP values to a queue and to a threshold ID.
priority-queue	Enables the egress expedite queue on a port.
queue-set	Maps a port to a queue set.
show mls qos interface	Displays quality of service (QoS) information.
srr-queue bandwidth shape	Assigns the shaped weights and enables bandwidth shaping on the four egress queues mapped to a port.

trust

To define a trust state for traffic classified through the class policy-map configuration or the class-map global configuration command, use the trust command in policy-map class configuration mode. Use the no form of this command to return to the default setting.

trust [ cos | dscp | ip-precedence ]

no trust [ cos | dscp | ip-precedence ]

Syntax Description

cos	(Optional) Classifies an ingress packet by using the packet class of service (CoS) value. For an untagged packet, the port default CoS value is used.
dscp	(Optional) Classifies an ingress packet by using the packet Differentiated Services Code Point (DSCP) values (most significant 6 bits of 8-bit service-type field). For a non-IP packet, the packet CoS value is used if the packet is tagged. If the packet is untagged, the default port CoS value is used to map CoS to DSCP.
ip-precedence	(Optional) Classifies an ingress packet by using the packet IP-precedence value (most significant 3 bits of 8-bit service-type field). For a non-IP packet, the packet CoS value is used if the packet is tagged. If the packet is untagged, the port default CoS value is used to map CoS to DSCP.

Command Default

The action is not trusted. If no keyword is specified when the command is entered, the default is dscp.

Command Modes

Policy-map class configuration

Command History

Release	Modification
Cisco IOS 15.0(2)EX	This command was introduced.

Usage Guidelines

Use this command to distinguish the quality of service (QoS) trust behavior for certain traffic from other traffic. For example, incoming traffic with certain DSCP values can be trusted. You can configure a class map to match and trust the DSCP values in the incoming traffic.

Trust values set with this command supersede trust values set with the mls qos trust interface configuration command.

The trust command is mutually exclusive with set policy-map class configuration command within the same policy map.

If you specify trust cos, QoS uses the received or default port CoS value and the CoS-to-DSCP map to generate a DSCP value for the packet.

If you specify trust dscp, QoS uses the DSCP value from the ingress packet. For non-IP packets that are tagged, QoS uses the received CoS value; for non-IP packets that are untagged, QoS uses the default port CoS value. In either case, the DSCP value for the packet is derived from the CoS-to-DSCP map.

If you specify trust ip-precedence, QoS uses the IP precedence value from the ingress packet and the IP-precedence-to-DSCP map. For non-IP packets that are tagged, QoS uses the received CoS value; for non-IP packets that are untagged, QoS uses the default port CoS value. In either case, the DSCP for the packet is derived from the CoS-to-DSCP map.

To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.

Examples

This example shows how to define a port trust state to trust incoming DSCP values for traffic classified with a default class:

Switch(config)# policy-map policy1
Switch(config-pmap)# class class-default
Switch(config-pmap-c)# trust dscp
Switch(config-pmap-c)# police 1000000 20000 exceed-action policed-dscp-transmit
Switch(config-pmap-c)# exit

You can verify your settings by entering the show policy-map privileged EXEC command.

Related Commands

Command	Description
class	Defines a traffic classification match criteria (through the police, set, and trust policy-map class configuration command) for the specified class-map name.
police	Defines a policer for classified traffic.
policy map	Creates or modifies a policy map that can be attached to multiple ports to specify a service policy.
set	Classifies IP traffic by setting a DSCP or IP-precedence value in the packet.
show policy-map	Displays QoS policy maps.

Bias-Free Language

Results

Chapter: QoS Commands

QoS Commands

class

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

class-map

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

debug qos

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Related Commands

match (class-map configuration)

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

mls qos

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

mls qos aggregate-policer

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

mls qos cos

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

mls qos dscp-mutation

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

mls qos map

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

Related Commands

mls qos queue-set output buffers

Syntax Description

Command Default

Command Modes