To load the base version of the protocol pack that is present in the Cisco IOS image of the Cisco router and to remove all other protocol packs, use the
default
ip
nbar
protocol-pack command in global configuration mode.
defaultipnbarprotocol-pack [protocol-pack]
Syntax Description
protocol-pack
(Optional) Protocol pack file path and name.
Command Modes
Global configuration (config)
Command History
Release
Modification
Cisco IOS XE Release 3.3S
This command was introduced.
15.2(2)T
This command was integrated into Cisco IOS Release 15.2(2)T.
Usage Guidelines
The protocol pack is a single compressed file that contains multiple Protocol Description Language (PDL) files and a manifest file. Before the protocol pack was introduced, PDLs had to be loaded separately. With network-based application recognition (NBAR) protocol pack, a set of protocols can be loaded, which helps NBAR to recognize additional protocols for classification on your network.
When the
default
ip
nbar
protocol-pack command is used, all protocol packs are removed from the router, except the base version that is provided with the Cisco IOS image in the router.
Examples
The following example shows how to load the default protocol pack and remove all other protocol packs:
Router# configure terminal
Router(config)# default ip nbar protocol-pack
Related Commands
Command
Description
ipnbarprotocol-pack
Loads a protocol pack.
showipnbarprotocol-pack
Displays protocol pack information.
description (class-map)
To add a description to the class map or the policy map, use the descriptioncommand in class-map configuration or policy-map configuration mode. To remove the description from the class map or the policy map, use the no form of this command.
descriptioncharacter-string
nodescription
Syntax Description
character-string
Comment or a description that is added to the class map or the policy map. The character-string cannot exceed 161 characters.
Command Default
If this command is not issued, a description does not exist.
Command Modes
Class-map configuration (config-cmap)
Policy-map configuration (config-pmap)
Command History
Release
Modification
12.4(4)T
This command was introduced.
12.2(18)ZY
This command was
integrated into Cisco IOS Release 12.2(18)ZY on the Catalyst 6500 series of switches equipped with the Programmable Intelligent Services Accelerator (PISA).
Usage Guidelines
The description command is meant solely as a comment to be put in the configuration to help you remember information about the class map or policy map, such as which packets are included within the class map.
Examples
The following example shows how to specify a description within the class map “ip-udp” and the policy map “fpm-policy”:
class-map type stack match-all ip-udp
description “match UDP over IP packets”
match field ip protocol eq 0x11 next udp
!
policy-map type access-control fpm-policy
description “drop worms and malicious attacks”
class ip-udp
service-policy fpm-udp-policy
!
!
interface gigabitEthernet 0/1
service-policy type access-control input fpm-policy
Related Commands
Command
Description
class-map
Creates a class map to be used for matching packets to a specified class.
policy-map
Creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.
description (service group)
To add a service-group description, use the description command in service-group configuration mode. To remove a service-group description, use the no form of this command.
descriptiondescriptive-text
nodescription
Syntax Description
descriptive-text
Service-group description. Enter up to 240 characters to describe the service group.
Use the description (service group) command to provide additional information about the service group, such as the account number, location, or subscriber name.
Examples
The following example shows how to create service group 1 and how to add information that identifies the subscriber account number in the description:
Router> enable
Router# configure terminal
Router(config)# service-group 1
Router(config-service-group)# descriptionsubscriber account number 105AB1
Router(config-service-group)# end
df
To change the algorithm for computing the delay factor (DF), use the df command in monitor parameters mode. To use the default DF algorithm (rfc4445) use the no form of this command.
Use the df command to modify the delay factor algorithm. The configured algorithm is used for both IP-CBR and MDI flows in a class. The ipdv-based algorithm is independent of the flow rate and reports only the delay caused by the network. The rfc4445-based algorithm is rate dependent and uses the configured flow rate. The rfc4445 based algorithm reports the sum of inter packet delay and network introduced delay.
Examples
This example shows how to configure the delay factor to the ipdv-based algorithm:
router(config-pmap-c-monitor)# df ipdv
Related Commands
Command
Description
showpolicy-maptypeperformance-traffic
Displays the policy-map information with the DF algorithm used.
disconnect qdm
To disconnect a Quality of Service Device Manager (QDM) client, use the
disconnectqdm command in EXEC or privileged EXEC mode.
disconnectqdm
[ clientclient-id ]
Syntax Description
client
(Optional) Specifies that a specific QDM client will be disconnected.
client-id
(Optional) Specifies the specific QDM identification number to disconnect. A QDM identification number can be a number from 0 to 2,147,483,647.
Command Default
This command has no default settings.
Command Modes
EXEC
Privileged EXEC
Command History
Release
Modification
12.1(1)E
This command was introduced.
12.1(5)T
This command was integrated into Cisco IOS Release 12.1(5)T.
12.2(14)SX
Support for this command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
This command was implemented on the Supervisor Engine 2 and integrated into Cisco IOS Release 12.2(17d)SXB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
Usage Guidelines
Use the
disconnectqdm command to disconnect all QDM clients that are connected to the router.
Use the
disconnectqdm [clientclient-id] command to disconnect a specific QDM client connected to a router. For instance, using the
disconnectqdmclient42 command will disconnect the QDM client with the ID 42.
Note
For the Cisco 7600 series QDM is not supported on Cisco Optical Services Module (OSM) interfaces.
Examples
The following example shows how to disconnect all connected QDM clients:
Router# disconnect qdm
The following example shows how to disconnect a specific QDM client with client ID 9:
Router# disconnect qdm client 9
Related Commands
Command
Description
showqdmstatus
Displays the status of connected QDM clients.
drop
To configure a traffic class to discard packets belonging to a specific class, use the drop command in policy-map class configuration mode. To disable the packet discarding action in a traffic class, use the no form of this command.
drop
nodrop
Syntax Description
This command has no arguments or keywords.
Command Default
Disabled
Command Modes
Policy-map class configuration (config-pmap-c)
Command History
Release
Modification
12.2(13)T
This command was introduced.
Usage Guidelines
Note the following points when configuring the drop command to unconditionally discard packets in a traffic class:
Discarding packets is the only action that can be configured in a traffic class. That is, no other actions can be configured in the traffic class.
When a traffic class is configured with the drop command, a “child” (nested) policy cannot be configured for this specific traffic class through the servicepolicy command.
Discarding packets cannot be configured for the default class known as the class-default class.
Examples
The following example shows how to create a traffic class called “class1” and configure it for use in a policy map called “policy1”. The policy map (service policy) is attached to output serial interface 2/0. All packets that match access-group 101 are placed in class1. Packets that belong to this class are discarded:
Router(config)# class-map class1
Router(config-cmap)# match access-group 101
Router(config-cmap)# exit
Router(config)# policy-map policy1
Router(config-pmap)# class class1
Router(config-pmap-c)# drop
Router(config-pmap-c)# exit
Router(config-pmap)# exit
Router(config)# interface serial2/0
Router(config-if)# service-policy output policy1
Router(config-if)# end
Related Commands
Command
Description
showclass-map
Displays all class maps and their matching criteria.
showpolicy-map
Displays the configuration of all classes for a specified service policy map or all classes for all existing policy maps.
showpolicy-mapinterface
Displays the packet statistics of all classes that are configured for all service policies either on the specified interface or subinterface or on a specific PVC on the interface.
dscp
To change the minimum and maximum packet thresholds for the differentiated services code point (DSCP) value, use the
dscp command in random-detect-group configuration mode. To return the minimum and maximum packet thresholds to the default for the DSCP value, use the
no form of this command.
Specifies the DSCP value. The DSCP value can be a number from 0 to 63, or it can be one of the following keywords:
ef,
af11,
af12,
af13,
af21,
af22,
af23,
af31,
af32,
af33,
af41,
af42,
af43,
cs1,
cs2,
cs3,
cs4,
cs5, or
cs7.
min-threshold
Minimum threshold in number of packets. The value range of this argument is from 1 to 4096. When the average queue length reaches the minimum threshold, Weighted Random Early Detection (WRED) randomly drops some packets with the specified DSCP value.
max-threshold
Maximum threshold in number of packets. The value range of this argument is the value of the
min-threshold argument to 4096. When the average queue length exceeds the maximum threshold, WRED drops all packets with the specified DSCP value.
mark-probability-denominator
(Optional) Denominator for the fraction of packets dropped when the average queue depth is at the maximum threshold. For example, if the denominator is 512, one out of every 512 packets is dropped when the average queue is at the maximum threshold. The value range is from 1 to 65536. The default is 10; one out of every ten packets is dropped at the maximum threshold.
Command Default
If WRED is using the DSCP value to calculate the drop probability of a packet, all entries of the DSCP table are initialized with the default settings shown in the table in the “Usage Guidelines” section.
Command Modes
Random-detect-group configuration
Command History
Release
Modification
12.1(5)T
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
This command must be used in conjunction with the
random-detect-group command.
Additionally, the
dscp command is available only if you specified the
dscp-based argument when using the
random-detect-group command.
The table below lists the DSCP default settings used by the
dscp command. The table below lists the DSCP value, and its corresponding minimum threshold, maximum threshold, and mark probability. The last row of the table (the row labeled “default”) shows the default settings used for any DSCP value not specifically shown in the table.
Table 1 dscp Default Settings
DSCP
(Precedence)
Minimum Threshold
Maximum Threshold
Mark Probability
af11
32
40
1/10
af12
28
40
1/10
af13
24
40
1/10
af21
32
40
1/10
af22
28
40
1/10
af23
24
40
1/10
af31
32
40
1/10
af32
28
40
1/10
af33
24
40
1/10
af41
32
40
1/10
af42
28
40
1/10
af43
24
40
1/10
cs1
22
40
1/10
cs2
24
40
1/10
cs3
26
40
1/10
cs4
28
40
1/10
cs5
30
40
1/10
cs6
32
40
1/10
cs7
34
40
1/10
ef
36
40
1/10
rsvp
36
40
1/10
default
20
40
1/10
Examples
The following example enables WRED to use the DSCP value af22. The minimum threshold for the DSCP value af22 is 28, the maximum threshold is 40, and the mark probability is 10.
Lists all or selected configured queueing strategies.
showqueueinginterface
Displays the queueing statistics of an interface or VC.
estimate bandwidth
To estimate the bandwidth needed per traffic class for given quality of service (QoS) targets based on traffic data, use the estimatebandwidth command in policy-map class configuration mode. To disable the estimated bandwidth processing, use the no form of this command.
(Optional) The packet loss rate; for example, a value of 999 means drop no more than one packet out of 999. The range forn is 50 to 1000000 packets.
delay-one-innmillisecondsn
(Optional) The packet delay time and probability; the range forn is 50 to 1000000 packets. The delay threshold; the range forn is 8 to 1000 milliseconds.
Command Default
Disabled
Command Modes
Policy-map class configuration (config-pmap-c)
Command History
Release
Modification
12.3(14)T
This command was introduced.
Usage Guidelines
Use the estimatebandwidthcommand to specify the target drop probability, the delay time and probability, and the timeframe.
If you specify a delay time, you must also specify a delay threshold.
If you issue the estimatebandwidth command with no keywords, the default target is drop less than 2 percent, which is the same as entering estimatebandwidthdrop-one-in500.
Examples
In the following example, the QoS targets are drop no more than one packet in 100, and delay no more than one packet in 100 by more than 50 milliseconds:
Specifies or modifies the bandwidth allocated for a class belonging to a policy map.
exponential-weighting-constant
To configure the exponential weight factor for the average queue size calculation for a Weighted Random Early Detection (WRED) parameter group, use the exponential-weighting-constantcommand in random-detect-group configuration mode. To return the exponential weight factor for the group to the default, use the no form of this command.
exponential-weighting-constantexponent
noexponential-weighting-constant
Syntax Description
exponent
Exponent from 1 to 16 used in the average queue size calculation.
Command Default
The default weight factor is 9.
Command Modes
Random-detect-group configuration (cfg-red-group)
Command History
Release
Modification
11.1(22)CC
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
When used, this command is issued after the random-detect-group command is entered.
Use this command to change the exponent used in the average queue size calculation for a WRED parameter group. The average queue size is based on the previous average and the current size of the queue. The formula is:
average = (old_average * (1-1/2^x)) + (current_queue_size * 1/2^x)
where x is the exponential weight factor specified in this command. Thus, the higher the factor, the more dependent the average is on the previous average.
Note
The default WRED parameter values are based on the best available data. We recommend that you do not change the parameters from their default values unless you have determined that your applications would benefit from the changed values.
For high values ofx, the previous average becomes more important. A large factor smooths out the peaks and lows in queue length. The average queue size is unlikely to change very quickly. The WRED process will be slow to start dropping packets, but it may continue dropping packets for a time after the actual queue size has fallen below the minimum threshold. The resulting slow-moving average will accommodate temporary bursts in traffic.
If the value ofxgets too high, WRED will not react to congestion. Packets will be sent or dropped as if WRED were not in effect.
For low values ofx, the average queue size closely tracks the current queue size. The resulting average may fluctuate with changes in the traffic levels. In this case, the WRED process will respond quickly to long queues. Once the queue falls below the minimum threshold, the process will stop dropping packets.
If the value ofxgets too low, WRED will overreact to temporary traffic bursts and drop traffic unnecessarily.
Examples
The following example shows how to configure the WRED group called sanjose with a weight factor of 10:
Configures a VC or PVC class with protected group or protected VC or PVC status for application to a VC or PVC bundle member.
random-detectexponential-weighting-constant
Configures the WRED and DWRED exponential weight factor for the average queue size calculation.
random-detect-group
Defines the WRED or DWRED parameter group.
showqueueing
Lists all or selected configured queueing strategies.
showqueueinginterface
Displays the queueing statistics of an interface or VC.
fair-queue (class-default)
To specify the number of dynamic queues to be reserved for use by the class-default class as part of the default class policy, use the
fair-queue command in policy-map class configuration mode. To delete the configured number of dynamic queues from the class-default policy, use the
no form of this command.
fair-queue [number-of-dynamic-queues]
nofair-queue [number-of-dynamic-queues]
Syntax Description
number-of-dynamic-queues
(Optional) A power of 2 that specifies the number of dynamic queues. Range is from 16 to 4096.
Command Default
The number of dynamic queues is derived from the interface or ATM permanent virtual circuit (PVC) bandwidth. See the table in the “Usage Guidelines” section for the default number of dynamic queues that weighted fair queueing (WFQ) and class-based WFQ (CBWFQ) use when they are enabled on an interface. See the table in the “Usage Guidelines” section for the default number of dynamic queues used when WFQ or CBWFQ is enabled on an ATM PVC.
Command Modes
Policy-map class configuration (config-pmap-c)
Command History
Release
Modification
12.0(5)T
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
This command can be used for the default class (commonly known as the class-default class) only. You can use it in conjunction with either the
queue-limit command or the
random-detectcommand.
The class-default class is the default class to which traffic is directed if that traffic does not satisfy the match criteria of other classes whose policy is defined in the policy map.
The table below lists the default number of dynamic queues that weighted fair queueing (WFQ) and class-based WFQ (CBWFQ) use when they are enabled on an interface.
Table 2 Default Number of Dynamic Queues as a Function of Interface Bandwidth
Bandwidth Range
Number of Dynamic Queues
Less than or equal to 64 kbps
16
More than 64 kbps and less than or equal to 128 kbps
32
More than 128 kbps and less than or equal to 256 kbps
64
More than 256 kbps and less than or equal to 512 kbps
128
More than 512 kbps
256
The table below lists the default number of dynamic queues used when WFQ or CBWFQ is enabled on an ATM PVC.
Table 3 Default Number of Dynamic Queues as a Function of ATM PVC Bandwidth
Bandwidth Range
Number of Dynamic Queues
Less than or equal to 128 kbps
16
More than 128 kbps and less than or equal to 512 kbps
32
More than 512 kbps and less than or equal to 2000 kbps
64
More than 2000 kbps and less than or equal to 8000 kbps
128
More than 8000 kbps
256
Examples
The following example shows how to configure policy for the default class included in the policy map called policy9. Packets that do not satisfy match criteria specified for other classes whose policies are configured in the same service policy are directed to the default class, for which 16 dynamic queues have been reserved. Because the
queue-limit command is configured, tail drop is used for each dynamic queue when the maximum number of packets are enqueued and additional packets arrive:
policy-map policy9
class class-default
fair-queue 16
queue-limit 20
The following example shows how to configure policy for the default class included in the policy map called policy8. The
fair-queue command reserves 20 dynamic queues to be used for the default class. For congestion avoidance, Weighted Random Early Detection (WRED) packet drop is used, not tail drop:
policy-map policy8
class class-default
fair-queue 64
random-detect
Related Commands
Command
Description
queue-limit
Specifies or modifies the maximum number of packets the queue can hold for a class policy configured in a policy map.
random-detect(interface)
Enables WRED or DWRED.
fair-queue (DWFQ)
To enable Versatile Interface Processor (VIP) distributed weighted fair queueing (DWFQ), use the
fair-queuecommand in interface configuration mode. To disable DWFQ, use the
no form of this command.
fair-queue
nofair-queue
Syntax Description
This command has no arguments or keywords.
Command Default
DWFQ is enabled by default for physical interfaces whose bandwidth is less than or equal to 2.048.
See the table in the “Usage Guidelines” section of this command for a list of the default queue lengths and thresholds.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.1
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
The
fair-queue(DWFQ) command enables DWFQ on an interface using a VIP2-40 or greater interface processor.
With DWFQ, packets are classified by flow. Packets with the same source IP address, destination IP address, source TCP or User Datagram Protocol (UDP) port, destination TCP or UDP port, and protocol belong to the same flow.
DWFQ allocates an equal share of the bandwidth to each flow.
The table below lists the default queue lengths and thresholds.
Table 4 Default Fair Queue Lengths and Thresholds
Queue or Threshold
Default
Congestive discard threshold
64 messages
Dynamic queues
256 queues
Reservable queues
0 queues
DWFQ can be configured on interfaces but not subinterfaces. It is not supported on Fast EtherChannel, tunnel, or other logical or virtual interfaces such as Multilink PPP (MLP).
Note
The [no]
fair-queue interface configuration command is not a valid configuration for member links of a multilink PPP interface. The command is only valid when configured on the multilink interface itself. Configuring [no]
fair-queue on a member link interface while bidirectional traffic is flowing could result in the output queue becoming stuck on the multilink interface. If this occurs, a
shut/noshut of the interface or a reload of the router may be required to clear the problem. An example configuration is provided in the “Examples” section to demonstrate the cause of this problem.
Examples
The following example shows how to enable DWFQ on High-Speed Serial Interface (HSSI) interface 0/0/0:
interface Hssi0/0/0
description 45Mbps to R2
ip address 10.200.14.250 255.255.255.252
fair-queue
The following example shows a basic configuration of two serial interfaces that results in the output queue becoming stuck on the multilink interface because of the
nofair-queue command:
configure terminal
interface serial0/0/0:0
no fair-queue
no max-reserved-bandwidth 90
tx-queue-limit 19
!
interface serial0/0/1:0
no fair-queue
no max-reserved-bandwidth 90
tx-queue-limit 19
Note
This sample configuration is provided for demonstration of a problem. Do not use this configuration.
Related Commands
Command
Description
fair-queue(WFQ)
Enables WFQ for an interface.
fair-queueaggregate-limit
Sets the maximum number of packets in all queues combined for DWFQ.
fair-queueindividual-limit
Sets the maximum individual queue depth for DWFQ.
fair-queuelimit
Sets the maximum queue depth for a specific DWFQ class.
fair-queueqos-group
Enables DWFQ and classifies packets based on the internal QoS-group number.
fair-queuetos
Enables DWFQ and classifies packets using the ToS field of packets.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showinterfacesfair-queue
Displays information and statistics about WFQ for a VIP-based interface.
fair-queue (policy-map class)
To specify the number of queues to be reserved for use by a traffic class, use the fair-queue command in policy-map class configuration mode. To delete the configured number of queues from the traffic class, use the no form of this command.
fair-queue [dynamic-queues]
nofair-queue [dynamic-queues]
Syntax Description
dynamic-queues
(Optional) A number specifying the number of dynamic conversation queues. The number can be in the range of 16 to 4096.
Command Default
No queues are reserved.
Command Modes
Policy-map class configuration
Command History
Release
Modification
12.0(5)T
This command was introduced.
12.0(5)XE
This command was integrated into Cisco IOS Release 12.0(5)XE and implemented on Versatile Interface Processor (VIP)-enabled Cisco 7500 series routers.
12.1(5)T
This command was integrated into Cisco IOS Release 12.1(5)T and was implemented on VIP-enabled Cisco 7500 series routers.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
On a VIP, the fair-queue command can be used for any traffic class (as opposed to non-VIP platforms, which can only use the fair-queue command in the default traffic class). The fair-queuecommand can be used in conjunction with either the queue-limit command or the random-detectexponential-weighting-constant command.
Examples
The following example shows how to configure the default traffic class for the policy map called policy9 to reserve ten queues for packets that do not satisfy match criteria specified for other traffic classes whose policy is configured in the same service policy. Because the queue-limit command is configured, tail drop is used for each queue when the maximum number of packets is enqueued and additional packets arrive:
policy-map policy9
class class-default
fair-queue 10
queue-limit 20
The following example shows how to configure a service policy called policy8 that is associated with a user-defined traffic class called class1. The fair-queue command reserves 20 queues to be used for the service policy. For congestion avoidance, Weighted Random Early Detection (WRED) or distributed WRED (DWRED) packet drop is used, not tail drop:
policy-map policy8
class class1
fair-queue 20
random-detect exponential-weighting-constant 14
Related Commands
Command
Description
classclass-default
Specifies the default traffic class for a service policy map.
queue-limit
Specifies or modifies the maximum number of packets the queue can hold for a class policy configured in a policy map.
random-detectexponential-weighting-constant
Configures the WRED and DWRED exponential weight factor for the average queue size calculation.
fair-queue (WFQ)
Note
Effective with Cisco IOS XE Release 2.6, Cisco IOS Release 15.0(1)S, and Cisco IOS Release 15.1(3)T, the
fair-queuecommand is hidden in interface configuration mode. Although this command is still available in Cisco IOS software, the CLI interactive Help does not display it if you attempt to view it by entering a question mark at the command line. This command will be completely removed in a future release, which means that you will need to use the appropriate replacement command (or sequence of commands). For more information (including a list of replacement commands), see the "Legacy QoS Command Deprecation" feature document in the
Cisco IOS XE Quality of Service Solutions Configuration Guide or the "Legacy QoS Command Deprecation" feature document in the
Cisco IOS Quality of Service Solutions Configuration Guide.
Note
Effective with Cisco IOS XE Release 3.2S, the
fair-queuecommand is replaced by a modular QoS CLI (MQC) command (or sequence of MQC commands). For the appropriate replacement command (or sequence of commands), see the "Legacy QoS Command Deprecation" feature document in the
Cisco IOS XE Quality of Service Solutions Configuration Guide.
To enable weighted fair queueing (WFQ), use the
fair-queue command in interface configuration or policy-map class configuration mode. To disable WFQ, use the
noform of this command.
(Optional) Number of messages allowed in each queue. The range is 1 to 4096 and the default is 64 messages. When a conversation reaches this threshold, new message packets are discarded.
Note
If you have hierarchical queueing framework (HQF) configured, then the values are 16 to 4096.
dynamic-queues
(Optional) Number of dynamic queues used for best-effort conversations (that is, a normal conversation not requiring any special network services). Values are
16,32,64,128,256,512,1024,2048, and
4096. See the tables in the
fair-queue(class-default) command for the default number of dynamic queues.
reservable-queues
(Optional) Number of reservable queues used for reserved conversations in the range 0 to 1000. The default is 0. Reservable queues are used for interfaces configured for features such as Resource Reservation Protocol (RSVP).
Command Default
Fair queueing is enabled by default for physical interfaces whose bandwidth is less than or equal to 2.048 Mbps and that do not use the following:
X.25 and Synchronous Data Link Control (SDLC) encapsulations
Link Access Procedure, Balanced (LAPB)
Tunnels
Loopbacks
Dialer
Bridges
Virtual interfaces
Fair queueing is not an option for the protocols listed above. However, if you enable custom queueing or priority queueing for a qualifying link, it overrides fair queueing, effectively disabling it. Additionally, fair queueing is automatically disabled if you enable the autonomous or silicon switching engine mechanisms.
Note
A variety of queueing mechanisms can be configured using multilink; for example, Multichassis Multilink PPP (MMP). However, if only PPP is used on a tunneled interface--for example, virtual private dialup network (VPND), PPP over Ethernet (PPPoE), or PPP over Frame Relay (PPPoFR)--no queueing can be configured on the virtual interface.
The number of dynamic queues is derived from the interface or ATM permanent virtual circuit (PVC) bandwidth. See the table in the
fair-queue(class-default) command for the default number of dynamic queues that WFQ and class-based WFQ (CBWFQ) use when they are enabled on an interface. See the table in the
fair-queue(class-default) command for the default number of dynamic queues used when WFQ and CBWFQ are enabled on an ATM PVC.
Command Modes
Interface configuration (config-if)
Policy-map class configuration (config-pmap-c)
Command History
Release
Modification
11.0
This command was introduced.
12.2(13)T
This command was modified to remove Apollo, VINES, and XNS from the list of protocols and traffic stream discrimination fields. These protocols were removed because Apollo Domain, Banyan VINES, and Xerox Network Systems (XNS) were removed in this release.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
12.2(31)SB
This command was integrated into Cisco IOS Release 12.2(31)SB.
12.2(33)SB
This command’s behavior was modified on the Cisco 10000 series router for the PRE3 and PRE4.
12.4(20)T
Support was added for HQF and user-defined classes using the Modular Quality of Service (QoS) Command-Line Interface (CLI) (MQC).
Cisco IOS XE Release 2.6
This command was modified. This command was hidden.
15.0(1)S
This command was modified. This command was hidden.
15.1(3)T
This command was modified. This command was hidden.
Cisco IOS XE Release 3.2S
This command was replaced by an MQC command (or sequence of MQC commands).
Usage Guidelines
High-Level Overview
This command enables WFQ. With WFQ, packets are classified by flow. For example, packets with the same source IP address, destination IP address, source TCP or User Datagram Protocol (UDP) port, destination TCP or UDP port, and protocol belong to the same flow; see the table below for a full list of protocols and traffic stream discrimination fields.
When you enable WFQ on an interface, WFQ provides traffic priority management that automatically sorts among individual traffic streams without requiring that you first define access lists. Enabling WFQ requires use of this command only.
When you enable WFQ on an interface, new messages for high-bandwidth traffic streams are discarded after the configured or default congestive discard threshold has been met. However, low-bandwidth conversations, which include control message conversations, continue to enqueue data. As a result, the fair queue may occasionally contain more messages than its configured threshold number specifies.
WFQ uses a traffic data stream discrimination registry service to determine which traffic stream a message belongs to. For each forwarding protocol, the table below shows the message attributes that are used to classify traffic into data streams.
Destination IP address (if message is not fragmented)
Source TCP/UDP port
Destination TCP/UDP port
Transparent bridging
Unicast: source MAC, destination MAC
Ethertype Service Advertising Protocol (SAP)/Subnetwork Access Protocol (SNAP) multicast: destination MAC address
Source-route bridging
Unicast: source MAC, destination MAC
SAP/SNAP multicast: destination MAC address
Novell NetWare
Source/destination network/host/socket
Level 2 protocol
All others (default)
Control protocols (one queue per protocol)
IP Precedence
IP Precedence, congestion in Frame Relay switching, and discard eligible (DE) flags affect the weights used for queueing.
IP Precedence, which is set by the host or by policy maps, is a number in the range from 0 to 7. Data streams of precedence
number are weighted so that they are given an effective bit rate of
number+1 times as fast as a data stream of precedence 0, which is normal.
FECN and BECN
In Frame Relay switching, message flags for forward explicit congestion notification (FECN), backward explicit congestion notification (BECN), and DE message flags cause the algorithm to select weights that effectively impose reduced queue priority. The reduced queue priority provides the application with “slow down” feedback and sorts traffic, giving the best service to applications within their committed information rate (CIR).
Fair Queueing, Custom Queueing, and Priority Queueing
Fair queueing is supported for all LAN and line (WAN) protocols except X.25, including LAPB and SDLC; see the notes in the section “Command Default.” Because tunnels are software interfaces that are themselves routed over physical interfaces, fair queueing is not supported for tunnels. Fair queueing is on by default for interfaces with bandwidth less than or equal to 2 Mbps.
Note
For Release 10.3 and earlier releases for the Cisco 7000 and 7500 routers with a Route Switch Processor (RSP) card, if you used the
tx-queue-limit command to set the transmit limit available to an interface on a Multiport Communications Interface (MCI) or serial port communications interface (SCI) card and you configured custom queueing or priority queueing for that interface, the configured transmit limit was automatically overridden and set to 1. With Cisco IOS Release 12.0 and later releases, for WFQ, custom queueing, and priority queueing, the configured transmit limit is derived from the bandwidth value set for the interface using the
bandwidth(interface)command. Bandwidth value divided by 512 rounded up yields the effective transmit limit. However, the derived value only applies in the absence of a
tx-queue-limit command; that is, a configured transmit limit overrides this derivation.
RSVP
When you configure Resource Reservation Protocol (RSVP) on an interface that supports fair queueing or on an interface that is configured for fair queueing with the reservable queues set to 0 (the default), the reservable queue size is automatically configured using the following method: interface bandwidth divided by 32 kbps. You can override this default by specifying a reservable queue other than 0. For more information on RSVP, refer to the chapter “Configuring RSVP” in the
Cisco IOS Quality of Service Solutions Configuration Guide .
Cisco 10000 Series Routers
In Cisco IOS Release 12.2(33)SB, the router removes the no fair-queue command from serial interfaces.
HQF
Beginning with Cisco IOS Release 12.4(20)T, if your image has HQF support, thefair-queue command is not enabled automatically under class default. You should enable the fair-queue command and any other supported queueing features before using an HQF-capable image.
Examples
The following example enables WFQ on serial interface 0, with a congestive threshold of 300. This threshold means that messages are discarded from the queueing system only when 300 or more messages have been queued and the message is in a data stream that has more than one message in the queue. The transmit queue limit is set to 2, based on the 384-kilobit (Kb) line set by the
bandwidth command:
interface serial 0
bandwidth 384
fair-queue 300
Unspecified parameters take the default values.
The following example requests a fair queue with a congestive discard threshold of 64 messages, 512 dynamic queues, and 18 RSVP queues:
interface serial 3/0
ip unnumbered ethernet 0/0
fair-queue 64 512 18
You can apply the
fair-queue command to a user-defined class as shown in the following example:
policy-map p1
class c1
bandwidth 1000
fair-queue
Related Commands
Command
Description
bandwidth(interface)
Sets a bandwidth value for an interface.
custom-queue-list
Assigns a custom queue list to an interface.
fair-queue(class-default)
Specifies the number of dynamic queues to be reserved for use by the class-default class as part of the default class policy.
fair-queue(DWFQ)
Enables DWFQ.
priority-group
Assigns the specified priority list to an interface.
priority-listdefault
Assigns a priority queue for those packets that do not match any other rule in the priority list.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showqueue
Displays the contents of packets inside a queue for a particular interface or VC.
showqueueing
Lists all or selected configured queueing strategies.
tx-queue-limit
Controls the number of transmit buffers available to a specified interface on the MCI and SCI cards.
air-queue aggregate-limit
To set the maximum number of packets in all queues combined for Versatile Interface Processor (VIP)-distributed weighted fair queueing (DWFQ), use the fair-queueaggregate-limitcommand in interface configuration mode. To return the value to the default, use the no form of this command.
fair-queueaggregate-limitaggregate-packets
nofair-queueaggregate-limit
Syntax Description
aggregate-packets
Total number of buffered packets allowed before some packets may be dropped. Below this limit, packets will not be dropped.
Command Default
The total number of packets allowed is based on the transmission rate of the interface and the available buffer space on the VIP.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.1 CC
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
In general, you should not change the maximum number of packets allows in all queues from the default. Use this command only if you have determined that you would benefit from using a different value, based on your particular situation.
DWFQ keeps track of the number of packets in each queue and the total number of packets in all queues.
When the total number of packets is below the aggregate limit, queues can buffer more packets than the individual queue limit.
When the total number of packets reaches the aggregate limit, the interface starts enforcing the individual queue limits. Any new packets that arrive for a queue that is over its individual queue limit are dropped. Packets that are already in the queue will not be dropped, even if the queue is over the individual limit.
In some cases, the total number of packets in all queues put together may exceed the aggregate limit.
Examples
The following example shows how to set the aggregate limit to 54 packets:
interface Fddi9/0/0
fair-queue tos
fair-queue aggregate-limit 54
Related Commands
Command
Description
fair-queuelimit
Sets the maximum queue depth for a specific DWFQ class.
fair-queueqos-group
Enables DWFQ and classifies packets based on the internal QoS-group number.
fair-queuetos
Enables DWFQ and classifies packets using the ToS field of packets.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showinterfacesfair-queue
Displays information and statistics about WFQ for a VIP-based interface.
fair-queue individual-limit
To set the maximum individual queue depth for Versatile Interface Processor (VIP)-distributed weighted fair queueing (DWFQ), use the fair-queueindividual-limitcommand in interface configuration mode. To return the value to the default, use the no form of this command.
fair-queueindividual-limitindividual-packet
nofair-queueindividual-limit
Syntax Description
individual-packet
Maximum number of packets allowed in each per-flow or per-class queue during periods of congestion.
Command Default
Half of the aggregate queue limit
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.1 CC
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
In general, you should not change the maximum individual queue depth from the default. Use this command only if you have determined that you would benefit from using a different value, based on your particular situation.
DWFQ keeps track of the number of packets in each queue and the total number of packets in all queues.
When the total number of packets is below the aggregate limit, queues can buffer more packets than the individual queue limit.
When the total number of packets reaches the aggregate limit, the interface starts enforcing the individual queue limits. Any new packets that arrive for a queue that is over its individual queue limit are dropped. Packets that are already in the queue will not be dropped, even if the queue is over the individual limit.
In some cases, the total number of packets in all queues put together may exceed the aggregate limit.
Examples
The following example shows how to set the individual queue limit to 27:
interface Fddi9/0/0
mac-address 0000.0c0c.2222
ip address 10.1.1.1 255.0.0.0
fair-queue tos
fair-queue individual-limit 27
Related Commands
Command
Description
fair-queue(class-default)
Sets the maximum number of packets in all queues combined for DWFQ.
fair-queuelimit
Sets the maximum queue depth for a specific DWFQ class.
fair-queueqos-group
Enables DWFQ and classifies packets based on the internal QoS-group number.
fair-queuetos
Enables DWFQ and classifies packets using the ToS field of packets.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showinterfacesfair-queue
Displays information and statistics about WFQ for a VIP-based interface.
fair-queue limit
To set the maximum queue depth for a specific Versatile Interface Processor (VIP)-distributed weighted fair queueing (DWFQ) class, use the fair-queuelimitcommand in interface configuration mode. To return the value to the default, use the no form of this command.
Number of the QoS group, as assigned by a committed access rate (CAR) policy or the Policy Propagation via Border Gateway Protocol (BGP) feature. The value can range from 1 to 99.
tosnumber
Two low-order IP Precedence bits of the type of service (ToS) field.
class-packet
Maximum number of packets allowed in the queue for the class during periods of congestion.
Command Default
The individual queue depth, as specified by the fair-queueindividual-limit command. If the fair-queueindividual-limit command is not configured, the default is half of the aggregate queue limit.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.1 CC
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
Use this command to specify the number queue depth for a particular class for class-based DWFQ. This command overrides the global individual limit specified by the fair-queueindividual-limit command.
In general, you should not change this value from the default. Use this command only if you have determined that you would benefit from using a different value, based on your particular situation.
Examples
The following example shows how to set the individual queue limit for ToS group 3 to 20:
interface Fddi9/0/0
mac-address 0000.0c0c.2222
ip address 10.1.1.1 255.0.0.0
fair-queue tos
fair-queue tos 3 limit 20
Related Commands
Command
Description
fair-queue(class-default)
Sets the maximum number of packets in all queues combined for DWFQ.
fair-queueqos-group
Enables DWFQ and classifies packets based on the internal QoS-group number.
fair-queuetos
Enables DWFQ and classifies packets using the ToS field of packets.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showinterfacesfair-queue
Displays information and statistics about WFQ for a VIP-based interface.
fair-queue qos-group
To enable Versatile Interface Processor (VIP)-distributed weighted fair queueing (DWFQ) and classify packets based on the internal QoS-group number, use the fair-queueqos-groupcommand in interface configuration mode. To disable QoS-group-based DWFQ, use the no form of this command.
fair-queueqos-group
nofair-queueqos-group
Syntax Description
This command has no arguments or keywords.
Command Default
QoS-group-based DWFQ is disabled.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.1CC
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
Use this command to enable QoS-group-based DWFQ, a type of class-based DWFQ. Class-based DWFQ overrides flow-based DWFQ. Therefore, this command overrides the fair-queue (DWFQ) command.
When this command is enabled, packets are assigned to different queues based on their QoS group. A QoS group is an internal classification of packets used by the router to determine how packets are treated by certain QoS features, such as DWFQ and committed access rate (CAR). Use a CAR policy or the QoS Policy Propagation via Border Gateway Protocol (BGP) feature to assign packets to QoS groups.
Specify a weight for each class. In periods of congestion, each group is allocated a percentage of the output bandwidth equal to the weight of the class. For example, if a class is assigned a weight of 50, packets from this class are allocated at least 50 percent of the outgoing bandwidth during periods of congestion.
Examples
The following example enables QoS-based DWFQ and allocates bandwidth for nine QoS groups (QoS groups 0 through 8):
Sets the maximum number of packets in all queues combined for DWFQ.
fair-queuelimit
Sets the maximum queue depth for a specific DWFQ class.
fair-queuetos
Enables DWFQ and classifies packets using the ToS field of packets.
fair-queueweight
Assigns a weight to a class for DWFQ.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showinterfacesfair-queue
Displays information and statistics about WFQ for a VIP-based interface.
fair-queue tos
To enable Versatile Interface Processor (VIP)-distributed weighted fair queueing (DWFQ) and classify packets using the type of service (ToS) field of packets, use the fair-queuetoscommand in interface configuration command. To disable ToS-based DWFQ, use the no form of this command.
fair-queuetos
nofair-queuetos
Syntax Description
This command has no arguments or keywords.
Command Default
Disabled
By default, class 0 is assigned a weight of 10; class 1 is assigned a weight of 20; class 2 is assigned a weight of 30; and class 3 is assigned a weight of 40.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.1CC
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
Use this command to enable ToS-based DWFQ, a type of class-based DWFQ. Class-based DWFQ overrides flow-based DWFQ. Therefore, this command overrides the fair-queue (DWFQ) command.
When this command is enabled, packets are assigned to different queues based on the two low-order IP Precedence bits in the ToS field of the packet header.
In periods of congestion, each group is allocated a percentage of the output bandwidth equal to the weight of the class. For example, if a class is assigned a weight of 50, packets from this class are allocated at least 50 percent of the outgoing bandwidth during periods of congestion.
If you wish to change the weights, use the fair-queueweightcommand.
Examples
The following example shows how to enable ToS-based DWFQ on the High-Speed Serial Interface (HSSI) interface 0/0/0:
interface Hssi0/0/0
description 45Mbps to R2
ip address 10.200.14.250 255.255.255.252
fair-queue
fair-queue tos
Related Commands
Command
Description
fair-queue(class-default)
Sets the maximum number of packets in all queues combined for DWFQ.
fair-queuelimit
Sets the maximum queue depth for a specific DWFQ class.
fair-queueqos-group
Enables DWFQ and classifies packets based on the internal QoS-group number.
fair-queueweight
Assigns a weight to a class for DWFQ.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showinterfacesfair-queue
Displays information and statistics about WFQ for a VIP-based interface.
fair-queue weight
To assign a weight to a class for Versatile Interface Processor (VIP)-distributed weighted fair queueing (DWFQ), use the fair-queueweightcommand in interface configuration mode. To remove the bandwidth allocated for the class, use the no form of this command.
Number of the quality of service (QoS) group, as assigned by a committed access rate (CAR) policy or the Policy Propagation via Border Gateway Protocol (BGP) feature. The value range is from 1 to 99.
tosnumber
Two low-order IP Precedence bits of the type of service (ToS) field. The value range is from 1 to 3.
weight
Percentage of the output link bandwidth allocated to this class. The sum of weights for all classes cannot exceed 99.
Command Default
For QoS DWFQ, unallocated bandwidth is assigned to QoS group 0.
For ToS-based DWFQ, class 0 is assigned a weight of 10; class 1 is assigned a weight of 20; class 2 is assigned a weight of 30; and class 3 is assigned a weight of 40.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.1CC
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
Use this command to allocate percentages of bandwidth for specific DWFQ classes. You must also enable class-based DWFQ on the interface with either the fair-queueqos-group or fair-queuetoscommand.
Enter this command once for every class to allocate bandwidth to the class.
For QoS-group-based DWFQ, packets that are not assigned to any QoS groups are assigned to QoS group 0. When assigning weights to QoS group class, remember the following guidelines:
One percent of the available bandwidth is automatically allocated to QoS group 0.
The total weight for all the other QoS groups combined cannot exceed 99.
Any unallocated bandwidth is assigned to QoS group 0.
For ToS-based DWFQ, remember the following guidelines:
One percent of the available bandwidth is automatically allocated to ToS class 0.
The total weight for all the other ToS classes combined cannot exceed 99.
Any unallocated bandwidth is assigned to ToS class 0.
Examples
The following example allocates bandwidth to different QoS groups. The remaining bandwidth (5 percent) is allocated to QoS group 0.
Enables DWFQ and classifies packets based on the internal QoS-group number.
fair-queuetos
Enables DWFQ and classifies packets using the ToS field of packets.
showinterfaces
Displays statistics for all interfaces configured on the router or access server.
showinterfacesfair-queue
Displays information and statistics about WFQ for a VIP-based interface.
feedback
To enable the context-status feedback messages from the interface or link, use the feedback command in IP Header Compression (IPHC)-profile configuration mode. To disable the context-status feedback messages, use the no form of this command.
feedback
nofeedback
Syntax Description
This command has no arguments or keywords.
Command Default
Context-status feedback messages are enabled.
Command Modes
IPHC-profile configuration (config-iphcp)
Command History
Release
Modification
12.4(9)T
This command was introduced.
Usage Guidelines
Intended for Use with IPHC Profiles
The feedback command is intended for use as part of an IPHC profile. An IPHC profile is used to enable and configure header compression on your network. For more information about using IPHC profiles to configure header compression, see the “Header Compression” module and the “Configuring Header Compression Using IPHC Profiles” module of the Cisco IOS Quality of Service Solutions Configuration Guide
, Release 12.4T.
Restriction
There are two types of IPHC profiles: Internet Engineering Task Force (IETF) profiles and van-jacobson profiles. The feedbackcommand is supported for IETF IPHC profiles only. The feedback command is not supported for van-jacobson IPHC profiles. For more information about IPHC profile types, see the “Header Compression” section of the Cisco IOS Quality of Service Solutions Configuration Guide
, Release 12.4T.
Prerequisite
Before using the feedback command, you must enable either TCP header compression or non-TCP header compression. To enable TCP header compression, use the tcp command. To enable non-TCP header compression, use the non-tcp command.
Disabling of Context-Status Messages
During header compression, a session context is defined. For each context, the session state is established and shared between the compressor and the decompressor. The context state consists of the full IP/UDP/RTP, IP/UDP, or IP/TCP headers, a few first-order differential values, a link sequence number, a generation number, and a delta encoding table.
When the decompressor loses synchronization with the compressor, the decompressor sends a context status message to the compressor with a list of context IDs to invalidate. The compressor then sends a full-header packet to the decompressor to reestablish a consistent state. Note that all packets for the invalid context IDs are discarded until a full-header packet is received for that context ID.
You can disable the sending of context-status messages either when the time it takes for the packet to traverse the uplink and the downlink portions of the data path is greater than the refresh period (in which case, the sending of the context-status message would not be useful) or when a feedback path does not exist.
Examples
The following is an example of an IPHC profile called profile2. In this example, context-status feedback messages have been disabled.
Enables non-TCP header compression within an IPHC profile.
tcp
Enables TCP header compression within an IPHC profile.
frame-relay interface-queue priority
To enable the Frame Relay PVC Interface Priority Queueing (FR PIPQ)
feature, use the
frame-relayinterface-queuepriority command in interface configuration mode.
To disable FR PIPQ, use the
no form of this command.To assign priority to
a permanent virtual circuit (PVC) within a Frame Relay map class, use the
frame-relayinterface-queuepriority command in map-class configuration mode.
To remove priority from a PVC within a Frame Relay map class, use the
no form of this command.
This command was integrated into Cisco IOS Release
12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX
train. Support in a specific 12.2SX release of this train depends on your
feature set, platform, and platform hardware.
Usage Guidelines
FR PIPQ must be enabled on the interface in order for the map-class
configuration of PVC priority to be effective.
Before you configure FR PIPQ using the
frame-relayinterface-queueprioritycommand, the following conditions must be met:
PVCs should be configured
to carry a single type of traffic.
The network should be
configured with adequate call admission control to prevent starvation of any of
the priority queues.
You will not be able to configure FR PIPQ if any queueing other than
first-in first out (FIFO) queueing is already configured at the interface
level. You will be able to configure FR PIPQ when weighted fair queueing (WFQ)
is in use, as long as WFQ is the default interface queueing method. Disabling
FR PIPQ will restore the interface to dual FIFO queueing if FRF.12 is enabled,
FIFO queueing if Frame Relay Traffic Shaping (FRTS) is enabled, or the default
queueing method for the interface.
Examples
The following example shows how to enable FR PIPQ on serial interface
0, and set the limits of the high, medium, normal, and low priority queues to
10, 20, 30, and 40 packets, respectively. PVC 100 is assigned high priority, so
all traffic destined for PVC 100 will be sent to the high priority interface
queue.
Displays statistics about PVCs for Frame Relay interfaces.
showinterfaces
Displays statistics for all interfaces configured on the
router or access server.
showqueue
Displays the contents of packets inside a queue for a
particular interface or VC.
showqueueing
Lists all or selected configured queueing strategies.
frame-relay ip rtp compression-connections
To
specify the maximum number of Real-Time Transport Protocol (RTP) header compression connections that can exist on a Frame Relay interface, use the frame-relayiprtpcompression-connections command in interface configuration mode. To restore the default, use the no form of this command.
frame-relayiprtpcompression-connectionsnumber
noframe-relayiprtpcompression-connections
Syntax Description
number
Maximum number of RTP header compression connections. The range is from 3 to 256.
Command Default
256 header compression connections
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
12.1(2)T
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
Before you can configure the maximum number of connections, RTP header compression must be configured on the interface using the frame-relayiprtpheader-compression command.
The number of RTP header compression connections must be set to the same value at each end of the connection.
Examples
The following example shows the configuration of a maximum of 150 RTP header compression connections on serial interface 0:
interface serial 0
encapsulation frame-relay
frame-relay ip rtp header-compression
frame-relay ip rtp compression-connections 150
Related Commands
Command
Description
frame-relayiprtpheader-compression
Enables RTP header compression for all Frame Relay maps on a physical interface.
frame-relaymapipcompress
Enables both RTP and TCP header compression on a link.
frame-relaymapiprtpheader-compression
Enables RTP header compression per DLCI.
showframe-relayiprtpheader-compression
Displays RTP header compression statistics for Frame Relay.
frame-relay ip rtp header-compression
To enable Real-Time Transport Protocol (RTP) header compression for all Frame Relay maps on a physical interface, use the frame-relayiprtpheader-compressioncommand in interface configuration mode. To disable the compression, use the no form of this command.
frame-relayiprtpheader-compression
[ active | passive ]
[periodic-refresh]
noframe-relayiprtpheader-compression
[ active | passive ]
[periodic-refresh]
Syntax Description
active
(Optional) Compresses all outgoing RTP packets.
passive
(Optional) Compresses the outgoing RTP/User Datagram Protocol (UDP)/IP header only if an incoming packet had a compressed header.
periodic-refresh
(Optional) Indicates that the compressed IP header will be refreshed periodically.
Command Default
Disabled.
By default, whatever type of header compression is configured on the interface will be inherited. If header compression is not configured on the interface, the active keyword will be used, but no header-compressionkeyword will appear on the showrunning-config command output.
Command Modes
Interface configuration
Command History
Release
Modification
11.3
This command was introduced.
12.3(2)T
This command was integrated into Cisco IOS Release 12.3(2)T. This command was modified to include the periodic-refresh keyword.
12.2(25)S
This command was integrated into Cisco IOS Release 12.2(25)S.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
When the frame-relayiprtpheader-compression command is used on the physical interface, all the interface maps inherit the command; that is, all maps will perform UDP and RTP IP header compression.
Examples
The following example shows how to enable RTP header compression for all Frame Relay maps on a physical interface:
Router> enable
Router# configure terminal
Router(config)# interface Serial2/0.1
Router(config-if)# frame-relay ip rtp header-compression
Router(config-if)# end
The following example shows how to enable RTP header compression, and the optionalperiodic-refresh keyword is specified:
Router> enable
Router# configure terminal
Router(config)# interface Serial2/0.2
Router(config-if)# frame-relay ip rtp header-compression periodic-refresh
Router(config-if)# end
Related Commands
Command
Description
frame-relayiprtpcompression-connections
Specifies maximum number of RTP header compression connections on a Frame Relay interface.
frame-relaymapipnocompress
Disables both RTP and TCP header compression on a link.
showframe-relayiprtpheader-compression
Displays RTP header compression statistics for Frame Relay.
frame-relay ip rtp priority
Note
Effective with Cisco IOS XE Release 2.6, Cisco IOS Release 15.0(1)S, and Cisco IOS Release 15.1(3)T, the
frame-relayiprtpprioritycommand is hidden. Although this command is still available in Cisco IOS software, the CLI interactive Help does not display it if you attempt to view it by entering a question mark at the command line. This command will be completely removed in a future release, which means that you will need to use the appropriate replacement command (or sequence of commands). For more information (including a list of replacement commands), see the "Legacy QoS Command Deprecation" feature document in the
Cisco IOS XE Quality of Service Solutions Configuration Guide or the "Legacy QoS Command Deprecation" feature document in the
Cisco IOS Quality of Service Solutions Configuration Guide.
Note
Effective with Cisco IOS XE Release 3.2S, the
frame-relayiprtpprioritycommand is replaced by a modular QoS CLI (MQC) command (or sequence of MQC commands). For the appropriate replacement command (or sequence of commands), see the "Legacy QoS Command Deprecation" feature document in the
Cisco IOS XE Quality of Service Solutions Configuration Guide .
To reserve a strict priority queue on a Frame Relay permanent virtual circuit (PVC) for a set of Real-Time Transport Protocol (RTP) packet flows belonging to a range of User Datagram Protocol (UDP) destination ports, use the
frame-relayiprtppriority command in map-class configuration mode. To disable the strict priority queue, use the
no form of this command.
The starting UDP port number. The lowest port number to which the packets are sent. A port number can be a number from 2000 to 65535.
port-number-range
The range of UDP destination ports. Number, which added to the
starting-rtp-port-number argument, yields the highest UDP port number. The range can be from 0 to 16383.
bandwidth
Maximum allowed bandwidth, in kbps. The bandwidth can range from 0 to 2000 kbps.
Command Default
No default behavior or values
Command Modes
Map-class configuration
Command History
Release
Modification
12.0(7)T
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Cisco IOS XE Release 2.6
This command was modified. This command was hidden.
15.0(1)S
This command was modified. This command was hidden.
15.1(3)T
This command was modified. This command was hidden.
Cisco IOS XE Release 3.2S
This command was replaced by an MQC command (or sequence of MQC commands).
Usage Guidelines
This command is most useful for voice applications, or other applications that are delay-sensitive. To use this command, you must first enter the
map-classframe-relay command. After the Frame Relay map class has been configured, it must then be applied to a PVC.
This command extends the functionality offered by the
iprtppriority command by supporting Frame Relay PVCs. The command allows you to specify a range of UDP ports whose voice traffic is guaranteed strict priority service over any other queues or classes using the same output interface. Strict priority means that if packets exist in the priority queue, they are dequeued and sent first--that is, before packets in other queues are dequeued.
Frame Relay Traffic Shaping (FRTS) and Frame Relay Fragmentation (FRF.12) must be configured before the
frame-relayiprtppriority command is used.
Compressed RTP (CRTP) can be used to reduce the bandwidth required per voice call. When using CRTP with Frame Relay, you must use the
encapsulationframe-relaycisco command instead of the
encapsulationframe-relayietfcommand.
Remember the following guidelines when configuring the
bandwidth parameter:
It is always safest to allocate to the priority queue slightly more than the known required amount of bandwidth, to allow room for network bursts.
The IP RTP Priority admission control policy takes RTP header compression into account. Therefore, while configuring the
bandwidth parameter of the
iprtppriority command you need to configure only for the bandwidth of the compressed call. Because the
bandwidth parameter is the maximum total bandwidth, you need to allocate enough bandwidth for all calls if there will be more than one call.
Configure a bandwidth that allows room for Layer 2 headers. The bandwidth allocation takes into account the payload plus the IP, UDP, and RTP headers but does not account for Layer 2 headers. Allowing 25 percent bandwidth for other overhead is conservative and safe.
The sum of all bandwidth allocation for voice and data flows on an interface cannot exceed 75 percent of the total available bandwidth, unless you change the default maximum reservable bandwidth. To change the maximum reservable bandwidth, use the
max-reserved-bandwidth command on the interface.
For more information on IP RTP Priority bandwidth allocation, refer to the section “IP RTP Priority” in the chapter “Congestion Management Overview” in the
Cisco IOS Quality of Service Solutions Configuration Guide.
Examples
The following example first configures the Frame Relay map class called voip and then applies the map class to PVC 100 to provide strict priority service to matching RTP packets:
map-class frame-relay voip
frame-relay cir 256000
frame-relay bc 2560
frame-relay be 600
frame-relay mincir 256000
no frame-relay adaptive-shaping
frame-relay fair-queue
frame-relay fragment 250
frame-relay ip rtp priority 16384 16380 210
interface Serial5/0
ip address 10.10.10.10 255.0.0.0
no ip directed-broadcast
encapsulation frame-relay
no ip mroute-cache
load-interval 30
clockrate 1007616
frame-relay traffic-shaping
frame-relay interface-dlci 100
class voip
frame-relay ip rtp header-compression
frame-relay intf-type dce
In this example, RTP packets on PVC 100 with UDP ports in the range from 16384 to 32764 (32764 = 16384 + 16380) will be matched and given strict priority service.
Related Commands
Command
Description
encapsulationframe-relay
Enables Frame Relay encapsulation.
iprtppriority
Reserves a strict priority queue for a set of RTP packet flows belonging to a range of UDP destination ports.
map-classframe-relay
Specifies a map class to define QoS values for an SVC.
max-reserved-bandwidth
Changes the percent of interface bandwidth allocated for CBWFQ, LLQ, and IP RTP Priority.
priority
Gives priority to a class of traffic belonging to a policy map.
showframe-relaypvc
Displays statistics about PVCs for Frame Relay interfaces.
showqueue
Displays the contents of packets inside a queue for a particular interface or VC.
showtraffic-shapequeue
Displays information about the elements queued by traffic shaping at the interface level or the DLCI level.
frame-relay ip tcp compression-connections
To specify the maximum number of TCP header compression connections that can exist on a Frame Relay interface, use the frame-relayiptcpcompression-connectionscommand in interface configuration mode. To restore the default, use the no form of this command.
frame-relayiptcpcompression-connectionsnumber
noframe-relayiptcpcompression-connections
Syntax Description
number
Maximum number of TCP header compression connections. The range is from 3 to 256.
Command Default
256 header compression connections
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
12.1(2)T
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
Before you can configure the maximum number of connections, TCP header compression must be configured on the interface using the frame-relayiptcpheader-compression command.
The number of TCP header compression connections must be set to the same value at each end of the connection.
Examples
The following example shows the configuration of a maximum of 150 TCP header compression connections on serial interface 0:
interface serial 0
encapsulation frame-relay
frame-relay ip tcp header-compression
frame-relay ip tcp compression-connections 150
Related Commands
Command
Description
frame-relayiptcpheader-compression
Enables TCP header compression for all Frame Relay maps on a physical interface.
frame-relaymapipcompress
Enables both RTP and TCP header compression on a link.
frame-relaymapiptcpheader-compression
Assigns header compression characteristics to an IP map that differ from the compression characteristics of the interface with which the IP map is associated.
showframe-relayiptcpheader-compression
Displays statistics and TCP/IP header compression information for the interface.
frame-relay ip tcp header-compression
To configure an
interface to ensure that the associated permanent virtual circuit (PVC) will always carry
outgoing TCP/IP headers in compressed form, use the
frame-relayiptcpheader-compressioncommand in interface configuration mode. To disable compression of TCP/IP packet headers on the interface, use the no form of this command.
frame-relayiptcpheader-compression [passive]
noframe-relayiptcpheader-compression
Syntax Description
passive
(Optional) Compresses the outgoing TCP/IP packet header only if an incoming packet had a compressed header.
Command Default
Active TCP/IP header compression; all outgoing TCP/IP packets are subjected to header compression.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
10.0
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
This command applies to interfaces that support
Frame Relay encapsulation, specifically serial ports and High-Speed Serial Interface (HSSI).
Frame Relay must be configured on the interface before this command can be used.
TCP/IP header compression and Internet Engineering Task Force (IETF)
encapsulation are mutually exclusive. If an interface is changed to IETF encapsulation, all encapsulation and compression characteristics are lost.
When you use this command to enable TCP/IP header compression, every IP map inherits the compression characteristics of the interface, unless header compression is explicitly rejected or modified by use of the frame-relaymapiptcpheadercompressioncommand.
We recommend that you shut down the interface prior to changing encapsulation types. Although this is not required, shutting down the interface ensures the interface is reset for the new type.
Examples
The following example configures serial interface 1 to use the default encapsulation (cisco) and passive TCP header compression:
interface serial 1
encapsulation frame-relay
frame-relay ip tcp header-compression passive
Related Commands
Command
Description
frame-relaymapiptcpheader-compression
Assigns header compression characteristics to an IP map different from the compression characteristics of the interface with which the IP map is associated.
frame-relay map ip compress
To enable both Real-Time Transport Protocol (RTP) and TCP header compression on a link, use the frame-relaymapipcompresscommand in interface configuration mode.
(Optional) Forwards broadcasts to the specified IP address.
active
(Optional) Compresses all outgoing RTP and TCP packets. This is the default.
passive
(Optional) Compresses the outgoing RTP and TCP header only if an incoming packet had a compressed header.
connectionsnumber
(Optional) Specifies the maximum number of RTP and TCP header compression connections. The range is from 3 to 256.
Command Default
RTP and TCP header compression are disabled.
The default maximum number of header compression connections is 256.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.3
This command was introduced.
12.1(2)T
This command was modified to enable the configuration of the maximum number of header compression connections.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
This command does not have a “no” form. That is, a command called noframe-relaymapipcompress does not exist.
Examples
The following example enables both RTP and TCP header compression on serial interface 1 and sets the maximum number of RTP and TCP header connections at 16:
interface serial 1
encapsulation frame-relay
ip address 10.108.175.110 255.255.255.0
frame-relay map ip 10.108.175.220 180 compress connections 16
Related Commands
Command
Description
frame-relayiprtpcompression-connections
Specifies the maximum number of RTP header compression connections on a Frame Relay interface.
frame-relayiptcpheader-compression
Enables TCP header compression for all Frame Relay maps on a physical interface.
frame-relaymapipnocompress
Disables both RTP and TCP header compression on a link.
frame-relaymapiprtpheader-compression
Enables RTP header compression for all Frame Relay maps on a physical interface.
showframe-relayiprtpheader-compression
Displays RTP header compression statistics for Frame Relay.
showframe-relayiptcpheader-compression
Displays statistics and TCP/IP header compression information for the interface.
frame-relay map ip nocompress
To disable both Real-Time Transport Protocol (RTP) and TCP header compression on a link, use the frame-relaymapipnocompresscommand in interface configuration mode.
(Optional) Forwards broadcasts to the specified IP address.
Command Default
No default behaviors or values
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
This command does not have a “no” form. That is, a command called noframe-relaymapipnocompressdoes not exist.
Examples
The following example disables RTP and TCP header compression on DLCI 180:
interface serial 1
encapsulation frame-relay
frame-relay map ip 10.108.175.220 180 nocompress
Related Commands
Command
Description
frame-relayiprtpheader-compression
Enables RTP header compression for all Frame Relay maps on a physical interface.
frame-relayiptcpheader-compression
Enables TCP header compression for all Frame Relay maps on a physical interface.
frame-relaymapipcompress
Enables RTP and TCP header compression on a link.
showframe-relayiprtpheader-compression
Displays RTP header compression statistics for Frame Relay.
showframe-relayiptcpheader-compression
Displays statistics and TCP/IP header compression information for the interface.
frame-relay map ip rtp header-compression
To enable Real-Time Transport Protocol (RTP) header compression per data-link connection identifier (DLCI), use the frame-relaymapiprtpheader-compressioncommand in interface configuration mode. To disable RTP header compression per DLCI and delete the DLCI, use the no form of this command.
(Optional) Forwards broadcasts to the specified IP address.
active
(Optional) Compresses outgoing RTP packets.
passive
(Optional) Compresses the outgoing RTP/
User Datagram Protocol (UDP)
/IP header only if an incoming packet had a compressed header.
periodic-refresh
(Optional) Refreshes the compressed IP header periodically.
connectionsnumber
(Optional) Specifies the maximum number of RTP header compression connections. The range is from 3 to 256.
Command Default
Disabled.
By default, whatever type of header compression is configured on the interface will be inherited. If header compression is not configured on the interface, the active keyword will be used, but no header-compression keyword will appear on the showrunning-config command output.
The default maximum number of header-compression connections is 256.
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
11.3
This command was introduced.
12.1(2)T
This command was integrated into Cisco IOS Release 12.1(2)T. This command was modified to enable the configuration of the maximum number of header compression connections.
12.3(2)T
This command was modified to include the periodic-refresh keyword.
12.2(25)S
This command was integrated into Cisco IOS Release 12.2(25)S.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
When this command is configured, the specified maps inherit RTP header compression. You can have multiple Frame Relay maps, with and without RTP header compression. If you do not specify the number of RTP header compression connections, the map will inherit the current value from the interface.
Examples
The following example shows how to enable RTP header compression on the Serial1/2.1 subinterface and set the maximum number of RTP header compression connections at 64:
Router> enable
Router# configure terminal
Router(config)# interface Serial1/2.1
Router(config-if)# encapsulation frame-relay
Router(config-if)# ip address 10.108.175.110 255.255.255.0
Router(config-if)# frame-relay map ip 10.108.175.220 180 rtp header-compression connections 64
Router(config-if)# end
The following example shows how to enable RTP header compression on the Serial1/1.0 subinterface and how to use the optional periodic-refresh keyword in the configuration:
Router> enable
Router# configure terminal
Router(config)# interface Serial1/1.0
Router(config-if)# encapsulation frame-relay
Router(config-if)# ip address 10.108.175.110 255.255.255.0
Router(config-if)# frame-relay map ip 10.108.175.220 180 rtp header-compression periodic-refresh
Router(config-if)# end
Related Commands
Command
Description
frame-relayiprtpcompression-connections
Specifies the maximum number of RTP header compression connections on a Frame Relay interface.
frame-relayiprtpheader-compression
Enables RTP header compression for all Frame Relay maps on a physical interface.
frame-relaymapipcompress
Enables both RTP and TCP header compression on a link.
showframe-relayiprtpheader-compression
Displays RTP header compression statistics for Frame Relay.
group (service group)
To add a member to a service group, use the groupcommand in Ethernet service configuration mode. To remove a member from a service group, use the no form of this command.
groupservice-group-identifier
nogroupservice-group-identifier
Syntax Description
service-group-identifier
Number of an existing service group to which the member will be added or removed.
Command Default
A member is not added.
Command Modes
Ethernet service configuration (config-if-srv)
Command History
Release
Modification
12.2(33)SRE
This command was introduced.
Usage Guidelines
Use the group (service group) command to add members (for example, service instances) to service groups and to remove members from service groups.
Cisco 7600 Series Router and Service Instances From Multiple Interfaces Are Not Allowed
The Cisco 7600 series router does not allow service instances to join the same group from multiple interfaces. On the Cisco 7600 series router, group members must come from the same interface, as shown the sample configuration below:
interface GigabitEthernet 2/0/0
service instance 1 ethernet
group 32
service-policy output policy3
service instance 2 ethernet
group 32
service instance 3 ethernet
group 37
interface GigabitEthernet 2/0/1
service instance 1 ethernet
group 32 |<--Disallowed because this group has members in g2/0/0 already| |
Examples
The following example shows how to add service instance 200 to service group 20:
Router> enable
Router# configure terminal
Router# interface GigabitEthernet 1/0/0
Router(config-if)# service instance 200 ethernet
Router(config-if-srv)# group 20
Router(config-if-srv)# end
hw-module slot (ESP Scheduling)
To handle the oversubscription of packets at the ingress side of an Embedded Service Processor, provide either a minimum bandwidth or a specific weight to a SIP based on which the excess bandwidth is divided among the low priority packets of the SIPs. Execute the hw-moduleslot command in global configuration mode. Use the no form of this command to either remove the minimum bandwidth assigned to a SIP or remove the excess weight configured for a SIP.
hw-moduleslotslot-numberqosinputlink
{ A | B }
[ bandwidthbandwidth_value ]
[ weightweightage_value ]
Syntax Description
slot-number
The slot number of the SIP for which the minimum bandwidth or excess weight needs to be configured.
qos
Enables configuration of the quality of service (QoS) policy to solve the oversubscription problem on the ingress side.
input
Enables the scheduling of packets on the ingress side.
link
Enables the configuration of each ESI link between the SIP and the ESP.
A
Specifies the A input QoS link for configuration of parameters.
B
Specifies the B input QoS link for configuration of parameters.
bandwidth
Provisions the configuration of a committted minimum bandwidth for the specified SIP.
bandwidth_value
The minimum bandwidth value in Kbps to be assigned to the SIP.
weight
Assigns the excess weight available for sharing to the SIP. Based on the excess weight assigned to the SIP, the available bandwidth that is left after processing the high priority packets is divided among the SIPs of low priority packets.
weightage_value
The weightage value to be assigned to the SIP for dividing the free bandwidth among the SPAs. The valid range for weightage value is 5 to 100.
Command Default
By default, the high priority packets are processed first.
Command Modes
Global configuration mode
Command History
Release
Modification
Cisco IOS Release
XE 2.1
This command was introduced as the hw-moduleslot(QoS) command.
Cisco IOS Release
XE 3.1S
The command was modified. The command was changed to the hw-moduleslot (ESP Scheduling) command and the link keyword was added.
Cisco IOS Release
XE 3.1.0
This command was modified. The linkAorlinkBkeyword sequences were added to provide specific bay information for configuring parameters on QoS input links.
Usage Guidelines
Oversubscription occurs at the SIP and ESP levels. To handle the oversubscription problem at the ESP level, use the hw-module slot command. A minimum bandwidth is assigned to a SIP that is connected through the ESI links, and a weight is assigned to the SIPs to divide the available excess bandwidth among the low priority packets.
To configure the minimum bandwidth service for a SIP, execute the hw-moduleslotslot-numberqosinputlinklink-indexbandwidthvalue_in_kbpscommand.
To assign a specific weight value to an ESI link connecting a SIP and an ESP, execute the hw-moduleslotslot-numberqosinputlinklink-indexweightweight-valuecommand.
Examples
The following example shows how to assign a minimum bandwidth to ESI Link A:
Router# config
Router(config)# hw-module slot 1 qos input link A bandwidth 512
The following example shows how to assign an excess weight of 150 to a SIP at slot 1 and connected through ESI Link A:
Router# config
Router(config)# hw-module slot 1 qos input link A weight 150
The following example shows how to display the available link options for ESP40 and SIP40 cards when there are two links configured:
Router(config)# hw-module slot 0 qos input link ?
A ESI Link A (Bay 0,2)
B ESI Link B (Bay 1,3)
The following example shows how to display the available link options for ESP40 and SIP10 cards when there is one link configured:
Router(config)# hw-module slot 1 qos input link ?
A ESI Link A (All Bays)
Related Commands
Command
Description
showplatformhardwareslot{f0|f1}serdesqos
Displays the excess weight and committed bandwidth settings for ESPs.
hw-module subslot (Channelized SPA Scheduling)
To handle the oversubscription of packets at the ingress side of a
SIP for a channelized SPA, assign the excess weight to the entire channelized
SPA using the
hw-modulesubslot command in global configuration mode. Use
the
no form of this command to remove the excess
weight configured for the SIP.
The slot number of the SIP, and the subslot number of the
channelized SPA for which the excess weight needs to be configured.
qos
Enables the configuration of the excess weight for low
priority packets on a channelized SPA to solve the oversubscription problem on
the ingress side.
weight
Assigns the excess weight to the channelized SPA. Based on
the excess weight assigned to the channelized SPA, the available bandwidth that
is left after processing the high priority packets is divided among the SPAs.
weightage_value
The weightage value to be assigned to the channelized SPA
for dividing the excess bandwidth among the channelized SPAs. The valid range
for weightage value is 5 to 100.
Command Default
By default, the high priority packets are processed first.
Command Modes
Global configuration mode
Command History
Release
Modification
3.1S
This command was introduced to assign weight during the
distribution of available bandwidth for channelized SPAs.
Usage Guidelines
A SIP contains different types of SPAs in each of its slots. To
assign the excess weight to a channelized SPA for low priority packets, the
hw-modulesubslotslot-subslotqosweightweight-valuecommand has been introduced.
Note
The option to configure minimum bandwidth for ‘strict-priority’
queue at port-level (interface-level) is deprecated as it is not applicable to
the current mode of operation. Existing configuration will be rejected with an
error.
Examples
The following example shows how to assign an excess weight of 200 to
a channelized SPA located at slot 1 and subslot 0: