Cisco IOS Quality of Service Solutions Command�Reference, Release�12.2
Commands: show queue -- vc-hold-queue
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show queue

Table Of Contents

show queue

show queueing

show queueing interface

show tech-support rsvp

show traffic-shape

show traffic-shape queue

show traffic-shape statistics

traffic-shape adaptive

traffic-shape fecn-adapt

traffic-shape group

traffic-shape rate

tx-ring-limit

vc-hold-queue


show queue

To display the contents of packets inside a queue for a particular interface or virtual circuit (VC), use the show queue privileged EXEC command.

show queue interface-name interface-number [vc [vpi/] vci]]

Syntax Description

interface-name

The name of the interface.

interface-number

The number of the interface.

vc

(Optional) For ATM interfaces only, shows the fair queueing configuration for a specified permanent virtual circuit (PVC). The name can be up to 16 characters long.

vpi/

(Optional) ATM network virtual path identifier (VPI) for this PVC. The absence of the "/" and a vpi value defaults the vpi value to 0.

On the Cisco 7200 and 7500 series routers, this value ranges from 0 to 255.

The vpi and vci arguments cannot both be set to 0; if one is 0, the other cannot be 0.

If this value is omitted, information for all VCs on the specified ATM interface or subinterface is displayed.

vci

(Optional) ATM network virtual channel identifier (VCI) for this PVC. This value ranges from 0 to 1 less than the maximum value set for this interface by the atm vc-per-vp command. Typically, lower values 0 to 31 are reserved for specific traffic (F4 Operation, Administration, and Maintenance (OAM), switched virtual circuit (SVC) signalling, Integrated Local Management Interface (ILMI), and so on) and should not be used.

The VCI is a 16-bit field in the header of the ATM cell. The VCI value is unique only on a single link, not throughout the ATM network, because it has local significance only.

The vpi and vci arguments cannot both be set to 0; if one is 0, the other cannot be 0.


Command Modes

Privileged EXEC

Command History

Release
Modification

10.2

This command was introduced.


Usage Guidelines

This command displays the contents of packets inside a queue for a particular interface or VC. The show queue command is primarily for internal debugging purposes and custom queueing.

This command does not support VIP-distributed Weighted Random Early Detection WRED (DWRED). You can use the vc keyword and the show queue command arguments to display output for a PVC only on Enhanced ATM port adapters (PA-A3) that support per-VC queueing.

This command is not recommended for use with the modular QoS CLI (MQC) features. Use the show policy interface command.

Examples

The following examples show sample output when the show queue command is entered and either weighted fair queueing (WFQ), WRED, or flow-based WRED are configured.

WFQ Example

The following is sample output from the show queue command for PVC 33 on the atm2/0.33 ATM subinterface. Two conversations are active on this interface. WFQ ensures that both data streams receive equal bandwidth on the interface while they have messages in the pipeline.

Router# show queue atm2/0.33 vc 33

Interface ATM2/0.33 VC 0/33
  Queueing strategy: weighted fair
  Total output drops per VC: 18149
  Output queue: 57/512/64/18149 (size/max total/threshold/drops)
     Conversations  2/2/256 (active/max active/max total)
     Reserved Conversations 3/3 (allocated/max allocated)

  (depth/weight/discards/tail drops/interleaves) 29/4096/7908/0/0
  Conversation 264, linktype: ip, length: 254
  source: 10.1.1.1, destination: 10.0.2.20, id: 0x0000, ttl: 59,
  TOS: 0 prot: 17, source port 1, destination port 1

  (depth/weight/discards/tail drops/interleaves) 28/4096/10369/0/0
  Conversation 265, linktype: ip, length: 254
  source: 10.1.1.1, destination: 10.0.2.20, id: 0x0000, ttl: 59,
  TOS: 32 prot: 17, source port 1, destination port 2

Table 31 describes the significant fields shown in the display.

Table 31 show queue Field Descriptions for WFQ 

Field
Description

Queueing strategy

Type of queueing active on this interface.

Total output drops per VC

Total output packet drops.

Output queue

Output queue size, in packets. Max total defines the aggregate queue size of all the WFQ flows. Threshold is the individual queue size of each conversation. Drops are the dropped packets from all the conversations in WFQ.

Conversations

WFQ conversation number. A conversation becomes inactive or times out when its queue is empty. Each traffic flow in WFQ is based on a queue and represented by a conversation. Max active is the number of active conversations that have occurred since the queueing feature was configured. Max total is the number of conversations allowed simultaneously.

Reserved Conversations

Traffic flows not captured by WFQ, such as class-based weighted fair queueing (CBWFQ) configured by the bandwidth command or a Resource Reservation Protocol (RSVP) flow, have a separate queue that is represented by a reserved conversation. Allocated is the current number of reserved conversations. Max allocated is the maximum number of allocated reserved conversations that have occurred.

depth

Queue depth for the conversation, in packets.

weight

Weight used in WFQ.

discards

Number of packets dropped from the conversation's queue.

tail drops

Number of packets dropped from the conversation when the queue is at capacity.

interleaves

Number of packets interleaved.

linktype

Protocol name.

length

Packet length.

source

Source IP address.

destination

Destination IP address.

id

Packet ID.

ttl

Time to live count.

TOS

IP type of service.

prot

Layer 4 protocol number.


Flow-Based WRED Example

The following is sample output from the show queue command issued for serial interface 1 on which flow-based WRED is configured. The output shows information for each packet in the queue; the data identifies the packet by number, the flow-based queue to which the packet belongs, the protocol used, and so forth.

Router# show queue Serial1

   Output queue for Serial1 is 2/0
   
   Packet 1, flow id:160, linktype:ip, length:118, flags:0x88
     source:10.1.3.4, destination:10.1.2.2, id:0x0000, ttl:59,
     TOS:32 prot:17, source port 1, destination port 515
       data:0x0001 0x0203 0x0405 0x0607 0x0809 0x0A0B 0x0C0D 
             0x0E0F 0x1011 0x1213 0x1415 0x1617 0x1819 0x1A1B 
   
   Packet 2, flow id:161, linktype:ip, length:118, flags:0x88
     source:10.1.3.5, destination:10.1.2.2, id:0x0000, ttl:59,
     TOS:64 prot:17, source port 1, destination port 515
       data:0x0001 0x0203 0x0405 0x0607 0x0809 0x0A0B 0x0C0D 
             0x0E0F 0x1011 0x1213 0x1415 0x1617 0x1819 0x1A1B 

Table 32 describes the significant fields shown in the display.

Table 32 show queue Field Descriptions for Flow-Based WRED 

Field
Description

Packet

Packet number.

flow id

Flow-based WRED number.

linktype

Protocol name.

length

Packet length.

flags

Internal version-specific flags.

source

Source IP address.

destination

Destination IP address.

id

Packet ID.

ttl

Time to live count.

prot

Layer 4 protocol number.

data

Packet data.


WRED Example

The following is sample output from the show queue command issued for serial interface 3 on which WRED is configured. The output has been truncated to show only 2 of the 24 packets.

Router# show queue Serial3

   Output queue for Serial3 is 24/0
   
   Packet 1, linktype:ip, length:118, flags:0x88
     source:10.1.3.25, destination:10.1.2.2, id:0x0000, ttl:59,
     TOS:192 prot:17, source port 1, destination port 515
       data:0x0001 0x0203 0x0405 0x0607 0x0809 0x0A0B 0x0C0D 
             0x0E0F 0x1011 0x1213 0x1415 0x1617 0x1819 0x1A1B 
   
   Packet 2, linktype:ip, length:118, flags:0x88
     source:10.1.3.26, destination:10.1.2.2, id:0x0000, ttl:59,
     TOS:224 prot:17, source port 1, destination port 515
       data:0x0001 0x0203 0x0405 0x0607 0x0809 0x0A0B 0x0C0D 
             0x0E0F 0x1011 0x1213 0x1415 0x1617 0x1819 0x1A1B 

Related Commands

Command
Description

atm vc-per-vp

Sets the maximum number of VCIs to support per VPI.

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 (WFQ)

Enables WFQ for an interface.

priority-group

Assigns the specified priority list to an interface.

random-detect (interface)

Enables WRED or DWRED.

random-detect flow

Enables flow-based WRED.

show frame-relay pvc

Displays information and statistics about WFQ for a VIP-based interface.

show queueing

Lists all or selected configured queueing strategies.


show queueing

To list all or selected configured queueing strategies, use the show queueing privileged EXEC command.

show queueing [custom | fair | priority | random-detect [interface atm-subinterface [vc [[vpi/vci]]]]

Syntax Description

custom

(Optional) Status of the custom queueing list configuration.

fair

(Optional) Status of the fair queueing configuration.

priority

(Optional) Status of the priority queueing list configuration.

random-detect

(Optional) Status of the Weighted Random Early Detection (WRED) and distributed WRED (DWRED) configuration, including configuration of flow-based WRED.

interface atm-subinterface

(Optional) Displays the WRED parameters of every virtual circuit (VC) with WRED enabled on the specified ATM subinterface.

vc

(Optional) Displays the WRED parameters associated with a specific VC. If desired, both the virtual path identifier (VPI) and virtual circuit identifier (VCI) values, or just the VCI value, can be specified.

vpi/

(Optional) Specifies the VPI. If the vpi argument is omitted, 0 is used as the VPI value for locating the permanent virtual circuit (PVC). If the vpi argument is specified, the / separator is required.

vci

(Optional) Specifies the VCI.


Defaults

If no keyword is entered, this command shows the configuration of all interfaces.

Command Modes

Privileged EXEC

Command History

Release
Modification

10.3

This command was introduced.

12.0(4)T

This command was integrated into Cisco IOS Release 12.0(4)T. The red keyword was changed to random-detect.

12.1(2)T

This command was integrated into Cisco IOS Release 12.1(2)T. This command was modified to include information about the Frame Relay PVC Interface Priority Queueing (FR PIPQ) feature.


Examples

FR PIPQ Example

The following sample output shows that FR PIPQ (referred to as "DLCI priority queue") is configured on serial interface 0. The output also shows the size of the four data-link connection identifier (DLCI) priority queues.

Router# show queueing

Current fair queue configuration:

  Interface           Discard     Dynamic      Reserved
                      threshold   queue count  queue count  
  Serial3/1           64          256          0
  Serial3/3           64          256          0

Current DLCI priority queue configuration: 

  Interface           High    Medium  Normal  Low 
                      limit   limit   limit   limit 
  Serial0             20      40      60      80 

Current priority queue configuration:

List   Queue  Args  
1      low    protocol ipx
1      normal protocol vines
1      normal protocol appletalk
1      normal protocol ip  
1      normal protocol decnet
1      normal protocol decnet_node
1      normal protocol decnet_rout
1      normal protocol decnet_rout
1      medium protocol xns
1      high   protocol clns
1      normal protocol bridge
1      normal protocol arp
Current custom queue configuration:
Current random-detect configuration:

Weighted Fair Queueing Example

The following is sample output from the show queueing command. There are two active conversations in serial interface 0. Weighted fair queueing (WFQ) ensures that both of these IP data streams—both using TCP—receive equal bandwidth on the interface while they have messages in the pipeline, even though more FTP data is in the queue than remote-procedure call (RCP) data.

Router# show queueing

Current fair queue configuration:
Interface           Discard     Dynamic      Reserved
                    threshold   queue count  queue count
  Serial0             64          256          0    
  Serial1             64          256          0    
  Serial2             64          256          0    
  Serial3             64          256          0    

Current priority queue configuration:
List   Queue  Args
1      high   protocol cdp         
2      medium interface Ethernet1  

Current custom queue configuration:

Current random-detect configuration:
  Serial5
    Queueing strategy:random early detection (WRED)
    Exp-weight-constant:9 (1/512)
    Mean queue depth:40

    Class   Random       Tail    Minimum    Maximum     Mark 
              drop       drop  threshold  threshold  probability 
      0       1401       9066        20         40      1/10 
      1          0          0        22         40      1/10 
      2          0          0        24         40      1/10 
      3          0          0        26         40      1/10 
      4          0          0        28         40      1/10 
      5          0          0        31         40      1/10 
      6          0          0        33         40      1/10 
      7          0          0        35         40      1/10 
      rsvp       0          0        37         40      1/10

Custom Queueing Example

The following is sample output from the show queueing custom command:

Router# show queueing custom

Current custom queue configuration:
List   Queue  Args
3      10     default
3      3      interface Tunnel3
3      3      protocol ip
3      3      byte-count 444 limit 3

Flow-Based WRED Example

The following is sample output from the show queueing random-detect command. The output shows that the interface is configured for flow-based WRED to ensure fair packet drop among flows. The random-detect flow average-depth-factor command was used to configure a scaling factor of 8 for this interface. The scaling factor is used to scale the number of buffers available per flow and to determine the number of packets allowed in the output queue of each active flow before the queue is susceptible to packet drop. The maximum flow count for this interface was set to 16 by the random-detect flow count command.

Router# show queueing random-detect

    Current random-detect configuration:
      Serial1
        Queueing strategy:random early detection (WRED)
        Exp-weight-constant:9 (1/512)
        Mean queue depth:29
        Max flow count:16       Average depth factor:8
        Flows (active/max active/max):39/40/16
    
        Class   Random       Tail    Minimum    Maximum     Mark
                  drop       drop  threshold  threshold  probability
          0         31          0         20         40     1/10
          1         33          0         22         40     1/10
          2         18          0         24         40     1/10
          3         14          0         26         40     1/10
          4         10          0         28         40     1/10
          5          0          0         31         40     1/10
          6          0          0         33         40     1/10
          7          0          0         35         40     1/10
         rsvp        0          0         37         40     1/10

DWRED Example

The following is sample output from the show queueing random-detect command for DWRED:

Current random-detect configuration:
  FastEthernet2/0/0
    Queueing strategy:fifo
    Packet drop strategy:VIP-based random early detection (DWRED)
    Exp-weight-constant:9 (1/512)
    Mean queue depth:0
    Queue size:0       Maximum available buffers:6308
    Output packets:5  WRED drops:0  No buffer:0

    Class   Random       Tail    Minimum    Maximum     Mark       Output
              drop       drop  threshold  threshold  probability  Packets
      0          0          0       109        218      1/10            5
      1          0          0       122        218      1/10            0
      2          0          0       135        218      1/10            0
      3          0          0       148        218      1/10            0
      4          0          0       161        218      1/10            0
      5          0          0       174        218      1/10            0
      6          0          0       187        218      1/10            0
      7          0          0       200        218      1/10            0

Table 33 describes the significant fields shown in the display.

Table 33 show queueing Field Descriptions 

Field
Description

Discard threshold

Number of messages allowed in each queue.

Dynamic queue count

Number of dynamic queues used for best-effort conversations.

Reserved queue count

Number of reservable queues used for reserved conversations.

High limit

High DLCI priority queue size in maximum number of packets.

Medium limit

Medium DLCI priority queue size, in maximum number of packets.

Normal limit

Normal DLCI priority queue size, in maximum number of packets.

Low limit

Low DLCI priority queue size, in maximum number of packets.

List

Custom queueing—Number of the queue list.

Priority queueing—Number of the priority list.

Queue

Custom queueing—Number of the queue.

Priority queueing—Priority queue level (high, medium, normal, or low keyword).

Args

Packet matching criteria for that queue.

Exp-weight-constant

Exponential weight factor.

Mean queue depth

Average queue depth. It is calculated based on the actual queue depth on the interface and the exponential weighting constant. It is a moving average. The minimum and maximum thresholds are compared against this value to determine drop decisions.

Class

IP Precedence value.

Random drop

Number of packets randomly dropped when the mean queue depth is between the minimum threshold value and the maximum threshold value for the specified IP Precedence value.

Tail drop

Number of packets dropped when the mean queue depth is greater than the maximum threshold value for the specified IP Precedence value.

Minimum threshold

Minimum WRED threshold, in number of packets.

Maximum threshold

Maximum WRED threshold, in number of packets.

Mark probability

Fraction of packets dropped when the average queue depth is at the maximum threshold.


Related Commands

Command
Description

custom-queue-list

Assigns a custom queue list to an interface.

exponential-weighting-constant

Configures the exponential weight factor for the average queue size calculation for a WRED parameter group.

fair-queue (WFQ)

Enables WFQ for an interface.

frame-relay interface-queue priority

Enables the FR PIPQ feature.

precedence (WRED group)

Configures a WRED group for a particular IP Precedence.

priority-group

Assigns the specified priority list to an interface.

priority-list interface

Establishes queueing priorities on packets entering from a given interface.

priority-list queue-limit

Specifies the maximum number of packets that can be waiting in each of the priority queues.

queue-list interface

Establishes queueing priorities on packets entering on an interface.

queue-list queue byte-count

Specifies how many bytes the system allows to be delivered from a given queue during a particular cycle.

random-detect (interface)

Enables WRED or DWRED.

random-detect flow average-depth-factor

Sets the multiplier to be used in determining the average depth factor for a flow when flow-based WRED is enabled.

random-detect flow count

Sets the flow count for flow-based WRED.

show interfaces

Displays the statistical information specific to a serial interface.

show queue

Displays the contents of packets inside a queue for a particular interface or VC.

show queueing interface

Displays the queueing statistics of an interface or VC.


show queueing interface

To display the queueing statistics of an interface or a virtual circuit (VC), use the show queueing interface privileged EXEC command.

show queueing interface interface-number [vc [[vpi/] vci]]

Syntax Description

interface-number

Specifies the number of the interface.

vc

(Optional) Shows the weighted fair queueing (WFQ) and Weighted Random Early Detection (WRED) parameters associated with a specific VC. If desired, both the virtual path identifier (VPI) and virtual channel identifier (VCI) values, or just the VCI value, can be specified.

vpi/

(Optional) Specifies the VPI. If the vpi argument is omitted, 0 is used as the VPI value for locating the permanent virtual circuit (PVC). If the vpi argument is specified, the / separator is required.

vci

(Optional) Specifies the VCI.


Command Modes

Privileged EXEC

Command History

Release
Modification

11.1(22)CC

This command was introduced.


Examples

The following is sample output from the show queueing interface command:

Router# show queueing interface atm2/0

  Interface ATM2/0 VC 201/201 
  Queueing strategy:random early detection (WRED)
    Exp-weight-constant:9 (1/512)
    Mean queue depth:49
    Total output drops per VC:759

    Class   Random       Tail    Minimum    Maximum     Mark
              drop       drop  threshold  threshold  probability
      0        165         26         30         50     1/10
      1        167         12         32         50     1/10
      2        173         14         34         50     1/10
      3        177         25         36         50     1/10
      4          0          0         38         50     1/10
      5          0          0         40         50     1/10
      6          0          0         42         50     1/10
      7          0          0         44         50     1/10
     rsvp        0          0         46         50     1/10

Related Commands

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 (WFQ)

Enables WFQ for an interface.

priority-group

Assigns the specified priority list to an interface.

random-detect (interface)

Enables WRED or DWRED.

random-detect (per VC)

Enables per-VC WRED or per-VC DWRED.

random-detect flow

Enables flow-based WRED.

show frame-relay pvc

Displays information and statistics about WFQ for a VIP-based interface.

show policy-map interface

Displays the configuration of all classes configured for all service policies on the specified interface or displays the classes for the service policy for a specific PVC on the interface.

show queueing

Lists all or selected configured queueing strategies.


show tech-support rsvp

To generate a report of all Resource Reservation Protocol (RSVP)-related information, use the show tech-support rsvp privileged EXEC command.

show tech-support rsvp

Syntax Description

This command has no arguments or keywords.

Command Modes

Privileged EXEC

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

This command is not required for normal use of the operating system. This command is useful when you contact technical support personnel with questions regarding RSVP. The show tech-support rsvp command generates a series of reports that can be useful to technical support personnel attempting to solve problems.

Any issues or caveats that apply to the show tech-support command also apply to this command. For example, the enable password, if configured, is not displayed in the output of the show running-config command.

The show tech-support rsvp command is equivalent to issuing the following commands:

show ip rsvp installed

show ip rsvp interface

show ip rsvp neighbor

show ip rsvp policy cops

show ip rsvp reservation

show ip rsvp sender

show running-config

show version

These commands are documented in various chapters of this book. Refer to the displays and descriptions for the individual commands for information about the show tech-support rsvp command display.

show traffic-shape

To display the current traffic-shaping configuration, use the show traffic-shape EXEC command.

show traffic-shape [interface-type interface-number]

Syntax Description

interface-type

(Optional) The type of the interface. If no interface is specified, traffic-shaping details for all configured interfaces are shown.

interface-number

(Optional) The number of the interface.


Command Modes

EXEC

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

You must have first enabled traffic shaping using the traffic-shape rate, traffic-shape group, or frame-relay traffic-shaping command to display traffic-shaping information.

Examples

The following is sample output from the show traffic-shape command:

Router# show traffic-shape

Interface   Fa0/0
       Access Target    Byte   Sustain   Excess    Interval  Increment Adapt
VC     List   Rate      Limit  bits/int  bits/int  (ms)      (bytes)   Active
-             1000000   6250   25000     25000     25        3125      - 

Table 34 describes the significant fields shown in the display.

Table 34 show traffic-shape Field Descriptions 

Field
Description

Interface

Interface type and number.

VC

Virtual circuit.

Note If you configure traffic shaping at a VC level instead of an interface level, a number appears in this field.

Access List

Number of the access list, if one is configured.

Target Rate

Rate that traffic is shaped to, in bits per second.

Byte Limit

Maximum number of bytes sent per internal interval.

Sustain bits/int

Configured sustained bits per interval.

Excess bits/int

Configured excess bits in the first interval.

Interval (ms)

Interval (in milliseconds) being used internally, which may be smaller than the committed burst divided by the committed information rate, if the router determines that traffic flow will be more stable with a smaller configured interval.

Increment (bytes)

Number of bytes that will be sustained per internal interval.

Adapt Active

Contains "BECN" if Frame Relay has backward explicit congestion notification (BECN) adaptation configured.


Related Commands

Command
Description

frame-relay cir

Specifies the incoming or outgoing committed information rate (CIR) for a Frame Relay virtual circuit.

frame-relay traffic-rate

Configures all the traffic-shaping characteristics of a virtual circuit (VC) in a single command.

frame-relay traffic-shaping

Enables both traffic shaping and per-VC queueing for all PVCs and SVCs on a Frame Relay interface.

show traffic-shape queue

Displays information about the elements queued by traffic shaping at the interface level or the DLCI level.

show traffic-shape statistics

Displays the current traffic-shaping statistics.

traffic-shape adaptive

Configures a Frame Relay subinterface to estimate the available bandwidth when BECN signals are received.

traffic-shape fecn-adapt

Replies to messages with the FECN bit (which are set with TEST RESPONSE messages with the BECN bit set).

traffic-shape group

Enables traffic shaping based on a specific access list for outbound traffic on an interface.

traffic-shape rate

Enables traffic shaping for outbound traffic on an interface.


show traffic-shape queue

To display information about the elements queued by traffic shaping at the interface level or the data-link connection identifier (DLCI) level, use the show traffic-shape queue EXEC command.

show traffic-shape queue [interface-number [dlci dlci-number]]

Syntax Description

interface-number

(Optional) The number of the interface.

dlci

(Optional) The specific DLCI for which you wish to display information about queued elements.

dlci-number

(Optional) The number of the DLCI.


Command Modes

EXEC

Command History

Release
Modification

11.2

This command was introduced.

12.0(3)XG

This command was integrated into Cisco IOS Release 12.0(3)XG. The dlci argument was added.

12.0(4)T

This command was integrated into Cisco IOS Release 12l.0(4)T. The dlci argument was added.

12.0(5)T

This command was integrated into Cisco IOS Release 12.0(5)T. This command was modified to include information on the special voice queue that is created using the queue keyword of the frame-relay voice bandwidth command.


Usage Guidelines

When no parameters are specified with this command, the output displays information for all interfaces and DLCIs containing queued elements. When a specific interface and DLCI are specified, information is displayed about the queued elements for that DLCI only.

Examples

The following is sample output for the show traffic-shape queue command when weighted fair queueing is configured on the map class associated with DLCI 16:

Router# show traffic-shape queue Serial1/1 dlci 16

Traffic queued in shaping queue on Serial1.1 dlci 16
  Queueing strategy: weighted fair
  Queueing Stats: 1/600/64/0 (size/max total/threshold/drops)
     Conversations  0/16 (active/max total)
     Reserved Conversations 0/2 (active/allocated)
  (depth/weight/discards) 1/4096/0
  Conversation 5, linktype: ip, length: 608
  
source: 172.21.59.21, destination: 255.255.255.255, id: 0x0006, ttl: 255,
  TOS: 0 prot: 17, source port 68, destination port 67

The following is sample output for the show traffic-shape queue command when priority queueing is configured on the map class associated with DLCI 16:

Router# show traffic-shape queue Serial1/1 dlci 16

Traffic queued in shaping queue on Serial1.1 dlci 16
  Queueing strategy: priority-group 4
  Queueing Stats: low/1/80/0 (queue/size/max total/drops)

Packet 1, linktype: cdp, length: 334, flags: 0x10000008

The following is sample output for the show traffic-shape queue command when first-come, first-serve queueing is configured on the map class associated with DLCI 16:

Router# show traffic-shape queue Serial1/1 dlci 16

Traffic queued in shaping queue on Serial1.1 dlci 16
  Queueing strategy: fcfs
  Queueing Stats: 1/60/0 (size/max total/drops)

Packet 1, linktype: cdp, length: 334, flags: 0x10000008

The following is sample output for the show traffic-shape queue command displaying statistics for the special queue for voice traffic that is created automatically when the frame-relay voice bandwidth command is entered:

Router# show traffic-shape queue serial 1 dlci 45   

 Voice queue attached to traffic shaping queue on Serial1 dlci 45
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Voice Queueing Stats: 0/100/0 (size/max/dropped)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Traffic queued in shaping queue on Serial1 dlci 45
   Queueing strategy: weighted fair
   Queueing Stats: 0/600/64/0 (size/max total/threshold/drops)
      Conversations  0/16 (active/max total)
      Reserved Conversations 0/2 (active/allocated)

Table 35 describes the significant fields shown in the display.

Table 35 show traffic-shape queue Field Descriptions 

Field
Description

Queueing strategy

When Frame Relay Traffic Shaping (FRTS) is configured, the queueing type can be weighted fair, custom-queue, priority-group, or fcfs (first-come, first-serve), depending on what is configured on the Frame Relay map class for this DLCI. The default is fcfs for FRTS. When generic traffic shaping is configured, the only queueing type available is weighted fair queueing (WFQ).

Queueing Stats

Statistics for the configured queueing strategy, as follows:

size—Current size of the queue.

max total—Maximum number of packets of all types that can be queued in all queues.

threshold—For WFQ, the number of packets in the queue after which new packets for high-bandwidth conversations will be dropped.

drops—Number of packets discarded during this interval.

Conversations active

Number of currently active conversations.

Conversations max total

Maximum allowed number of concurrent conversations.

Reserved Conversations active

Number of currently active conversations reserved for voice.

Reserved Conversations allocated

Maximum configured number of conversations reserved.

depth

Number of packets currently queued.

weight

Number used to classify and prioritize the packet.

discards

Number of packets discarded from queues.

Packet

Number of queued packet.

linktype

Protocol type of the queued packet. (cdp = Cisco Discovery Protocol)

length

Number of bytes in the queued packet.

flags

Number of flag characters in the queued packet.

source

Source IP address.

destination

Destination IP address.

id

Packet ID.

ttl

Time to live count.

TOS

IP type of service.

prot

Layer 4 protocol number. Refer to RFC 943 for a list of protocol numbers. (17 = User Datagram Protocol (UDP))

source port

Port number of source port.

destination port

Port number of destination port.


Related Commands

Command
Description

show frame-relay fragment

Displays Frame Relay fragmentation details.

show frame-relay pvc

Displays statistics about PVCs for Frame Relay interfaces.

show frame-relay vofr

Displays details about FRF.11 subchannels being used on VoFR DLCIs.

show traffic-shape

Displays the current traffic-shaping configuration.

show traffic-shape statistics

Displays the current traffic-shaping statistics.


show traffic-shape statistics

To display the current traffic-shaping statistics, use the show traffic-shape statistics EXEC command.

show traffic-shape statistics [interface-type interface-number]

Syntax Description

interface-type

(Optional) The type of the interface. If no interface is specified, traffic-shaping statistics for all configured interfaces are shown.

interface-number

(Optional) The number of the interface.


Command Modes

EXEC

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

You must have first enabled traffic shaping using the traffic-shape rate, traffic-shape group, or frame-relay traffic-shaping command to display traffic-shaping information.

Examples

The following is sample output from the show traffic-shape statistics command:

Router# show traffic-shape statistics

          Access Queue     Packets   Bytes     Packets   Bytes     Shaping
I/F       List   Depth                         Delayed   Delayed   Active
Et0       101    0         2         180       0         0         no
Et1              0         0         0         0         0         no

Table 36 describes the significant fields shown in the display.

Table 36 show traffic-shape statistics Field Descriptions 

Field
Description

I/F

Interface.

Access List

Number of the access list.

Queue Depth

Number of messages in the queue.

Packets

Number of packets sent through the interface.

Bytes

Number of bytes sent through the interface.

Packets Delayed

Number of packets sent through the interface that were delayed in the traffic-shaping queue.

Bytes Delayed

Number of bytes sent through the interface that were delayed in the traffic-shaping queue.

Shaping Active

Contains "yes" when timers indicate that traffic shaping is occurring and "no" if traffic shaping is not occurring.


Related Commands

Command
Description

frame-relay traffic-shaping

Enables both traffic shaping and per-VC queueing for all PVCs and SVCs on a Frame Relay interface.

show interfaces

Displays statistics for all interfaces configured on the router or access server.

show ip rsvp neighbor

Displays RSVP-related interface information.

traffic-shape adaptive

Configures a Frame Relay subinterface to estimate the available bandwidth when BECN signals are received.

traffic-shape group

Enables traffic shaping based on a specific access list for outbound traffic on an interface.

traffic-shape rate

Enables traffic shaping for outbound traffic on an interface.


traffic-shape adaptive

To configure a Frame Relay subinterface to estimate the available bandwidth when backward explicit congestion notification (BECN) signals are received, use the traffic-shape adaptive interface configuration command. To disregard the BECN signals and not estimate the available bandwidth, use the no form of this command.

traffic-shape adaptive bit-rate

no traffic-shape adaptive

Syntax Description

bit-rate

Lowest bit rate that traffic is shaped to, in bits per second. The default bit rate value is 0.


Defaults

This command is not enabled by default.

Command Modes

Interface configuration

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

This command specifies the boundaries in which traffic will be shaped when BECN signals are received. You must enable traffic shaping on the interface with the traffic-shape rate or traffic-shape group command before you can use the traffic-shape adaptive command.

The bit rate specified for the traffic-shape rate command is the upper limit, and the bit rate specified for the traffic-shape adaptive command is the lower limit to which traffic is shaped when BECN signals are received on the interface. The rate actually shaped to will be between these two bit rates.

You should configure this command and the traffic-shape fecn-adapt command on both ends of the connection to ensure adaptive traffic shaping over the connection, even when traffic is flowing primarily in one direction. The traffic-shape fecn-adapt command configures the router to reflect forward explicit congestion notification (FECN) signals as BECN signals.

Examples

The following example configures traffic shaping on serial interface 0.1 with an upper limit of 128 kbps and a lower limit of 64 kbps. This configuration allows the link to run from 64 to 128 kbps, depending on the congestion level.

interface serial 0
 encapsulation-frame-relay
interface serial 0.1
 traffic-shape rate 128000
 traffic-shape adaptive 64000
 traffic-shape fecn-adapt

Related Commands

Command
Description

show traffic-shape

Displays the current traffic-shaping configuration.

show traffic-shape statistics

Displays the current traffic-shaping statistics.

traffic-shape fecn-adapt

Replies to messages with the FECN bit (which are set with TEST RESPONSE messages with the BECN bit set).

traffic-shape group

Enables traffic shaping based on a specific access list for outbound traffic on an interface.

traffic-shape rate

Enables traffic shaping for outbound traffic on an interface.


traffic-shape fecn-adapt

To reply to messages with the forward explicit congestion notification (FECN) bit (which are sent with TEST RESPONSE messages with the BECN bit set), use the traffic-shape fecn-adapt interface configuration command. To stop backward explicit congestion notification (BECN) signal generation, use the no form of this command.

traffic-shape fecn-adapt

no traffic-shape fecn-adapt

Syntax Description

This command has no arguments or keywords.

Defaults

Traffic shaping is disabled.

Command Modes

Interface configuration

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

Enable traffic shaping on the interface with the traffic-shape rate or traffic-shape group command. FECN is available only when traffic shaping is configured.

Use this command to reflect FECN bits as BECN bits. Reflecting FECN bits as BECN bits notifies the sending DTE that it is transmitting at a rate too fast for the DTE to handle. Use the traffic-shape adaptive command to configure the router to adapt its transmission rate when it receives BECN signals.

You should configure this command and the traffic-shape adaptive command on both ends of the connection to ensure adaptive traffic shaping over the connection, even when traffic is flowing primarily in one direction.

Examples

The following example configures traffic shaping on serial interface 0.1 with an upper limit of 128 kbps and a lower limit of 64 kbps. This configuration allows the link to run from 64 to 128 kbps, depending on the congestion level. The router reflects FECN signals as BECN signals.

interface serial 0
 encapsulation-frame-relay
interface serial 0.1
 traffic-shape rate 128000
 traffic-shape adaptive 64000
 traffic-shape fecn-adapt

Related Commands

Command
Description

show traffic-shape

Displays the current traffic-shaping configuration.

show traffic-shape statistics

Displays the current traffic-shaping statistics.

traffic-shape adaptive

Configures a Frame Relay subinterface to estimate the available bandwidth when BECN signals are received.

traffic-shape group

Enables traffic shaping based on a specific access list for outbound traffic on an interface.

traffic-shape rate

Enables traffic shaping for outbound traffic on an interface.


traffic-shape group

To enable traffic shaping based on a specific access list for outbound traffic on an interface, use the traffic-shape group interface configuration command. To disable traffic shaping on the interface for the access list, use the no form of this command.

traffic-shape group access-list bit-rate [burst-size [excess-burst-size]]

no traffic-shape group access-list

Syntax Description

access-list

Number of the access list that controls the packets that traffic shaping is applied to on the interface.

bit-rate

Bit rate that traffic is shaped to, in bits per second. This is the access bit rate that you contract with your service provider, or the service levels you intend to maintain.

burst-size

(Optional) Sustained number of bits that can be sent per interval. On Frame Relay interfaces, this is the Committed Burst size contracted with your service provider.

excess-burst-size

(Optional) Maximum number of bits that can exceed the burst size in the first interval in a congestion event. On Frame Relay interfaces, this is the Excess Burst size contracted with your service provider. The default is equal to the burst-size argument.


Defaults

Traffic shaping is not on by default.

Command Modes

Interface configuration

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

Generic traffic shaping is not supported on ISDN and dialup interfaces. Is is also not supported on nongeneric routing encapsulation tunnel interfaces. Traffic shaping is not supported with flow switching.

Traffic shaping uses queues to limit surges that can congest a network. Data is buffered and then sent into the network in regulated amounts to ensure that traffic will fit within the promised traffic envelope for the particular connection.

The traffic-shape group command allows you to specify one or more previously defined access list to shape traffic on the interface. You must specify one traffic-shape group command for each access list on the interface.

The traffic-shape group command supports both standard and extended access lists.

Use traffic shaping if you have a network with differing access rates or if you are offering a subrate service. You can configure the values according to your contract with your service provider or the service levels you intend to maintain.

An interval is calculated as follows:

If the burst-size is not equal to zero, the interval is the burst-size divided by the bit-rate.

If the burst-size is zero, the interval is the excess-burst-size divided by the bit-rate.

Traffic shaping is supported on all media and encapsulation types on the router. To perform traffic shaping on Frame Relay virtual circuits, you can also use the frame-relay traffic-shaping command. For more information on Frame Relay Traffic Shaping, refer to the "Configuring Frame Relay" chapter in the Cisco IOS Wide-Area Networking Configuration Guide.

If traffic shaping is performed on a Frame Relay network with the traffic-shape rate command, you can also use the traffic-shape adaptive command to specify the minimum bit rate to which the traffic is shaped.

Examples

The following example enables traffic that matches access list 101 to be shaped to a certain rate and traffic matching access list 102 to be shaped to another rate on the interface:

interface serial 1
 traffic-shape group 101 128000 16000 8000
 traffic-shape group 102 130000 10000 1000

Related Commands

Command
Description

access-list (IP Standard)

Defines a standard IP access list.

show traffic-shape

Displays the current traffic-shaping configuration.

show traffic-shape statistics

Displays the current traffic-shaping statistics.

traffic-shape adaptive

Configures a Frame Relay subinterface to estimate the available bandwidth when BECN signals are received.

traffic-shape fecn-adapt

Replies to messages with the FECN bit (which are set with TEST RESPONSE messages with the BECN bit set).

traffic-shape rate

Enables traffic shaping for outbound traffic on an interface.


traffic-shape rate

To enable traffic shaping for outbound traffic on an interface, use the traffic-shape rate interface configuration command. To disable traffic shaping on the interface, use the no form of this command.

traffic-shape rate bit-rate [burst-size [excess-burst-size]] [buffer-limit]]

no traffic-shape rate

Syntax Description

bit-rate

Bit rate that traffic is shaped to, in bits per second. This is the access bit rate that you contract with your service provider, or the service levels you intend to maintain.

burst-size

(Optional) Sustained number of bits that can be sent per interval. On Frame Relay interfaces, this is the Committed Burst size contracted with your service provider.

excess-burst-size

(Optional) Maximum number of bits that can exceed the burst size in the first interval in a congestion event. On Frame Relay interfaces, this is the Excess Burst size contracted with your service provider. The default is equal to the burst-size argument.

buffer-limit

(Optional) Maximum buffer limit in bps. Valid entries are numbers in the range of 0 to 4096.


Defaults

Traffic shaping is disabled.

Command Modes

Interface configuration

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

Generic traffic shaping is not supported on ISDN and dialup interfaces. Is is also not supported on nongeneric routing encapsulation tunnel interfaces. Traffic shaping is not supported with flow switching.

Traffic shaping uses queues to limit surges that can congest a network. Data is buffered and then sent into the network in regulated amounts to ensure that traffic will fit within the promised traffic envelope for the particular connection.

Use traffic shaping if you have a network with differing access rates or if you are offering a subrate service. You can configure the values according to your contract with your service provider or the service levels you intend to maintain.

An interval is calculated as follows:

If the burst-size is not equal to zero, the interval is the burst-size divided by the bit-rate.

If the burst-size is zero, the interval is the excess-burst-size divided by the bit-rate.

Traffic shaping is supported on all media and encapsulation types on the router. To perform traffic shaping on Frame Relay virtual circuits, you can also use the frame-relay traffic-shaping command. For more information on Frame Relay Traffic Shaping, refer to the "Configuring Frame Relay" chapter in the Cisco IOS Wide-Area Networking Configuration Guide.

If traffic shaping is performed on a Frame Relay network with the traffic-shape rate command, you can also use the traffic-shape adaptive command to specify the minimum bit rate to which the traffic is shaped.

Examples

The following example enables traffic shaping on serial interface 0 using the bandwidth required by the service provider:

interface serial 0
 traffic-shape rate 128000 16000 8000

Related Commands

Command
Description

show traffic-shape

Displays the current traffic-shaping configuration.

show traffic-shape statistics

Displays the current traffic-shaping statistics.

traffic-shape adaptive

Configures a Frame Relay subinterface to estimate the available bandwidth when BECN signals are received.

traffic-shape fecn-adapt

Replies to messages with the FECN bit (which are set with TEST RESPONSE messages with the BECN bit set).

traffic-shape group

Enables traffic shaping based on a specific access list for outbound traffic on an interface.


tx-ring-limit

To limit the number of particles or packets that can be used on a transmission ring on an interface, use the tx-ring-limit ATM VC configuration command. To not limit the number of particles or packets that can be used on an interface, use the no form of this command.

tx-ring-limit ring-limit

no tx-ring-limit ring-limit

Syntax Description

ring-limit

Specifies the maximum number of allowable particles or packets that can be placed on the transmission ring.


Defaults

This command has no default behavior or values.

Command Modes

ATM VC Configuration

Command History

Release
Modification

12.0(7)XE1

This command was introduced.

12.0(9)S

This command was integrated into Cisco IOS Release 12.0 S.

12.1(5)T

This command was integrated into Cisco IOS Release 12.1(5)T.


Usage Guidelines

The transmission ring limit value is limited to values from 3 to 6000.

For Cisco 2600 series routers and Cisco 3600 series routers, you can specify the number of packets. For Cisco 7200 series routers and Cisco 7500 series routers, you can specify the number of particles.

This command allows you to reduce the size of the FIFO (first-in, first-out) queue. Reducing the size of the transmit ring in the queue has two benefits:

It reduces the amount of time packets wait in the FIFO queue before being segmented.

It accelerates the use of QoS in the Cisco IOS software.

Examples

The following example configures the transmission ring limit to seven particles on an ATM interface:

Router(config)# interface atm 1/0/0

Router(config-if)# atm pvc 32 0 32 aal5snap 10000 8000 2000 tx-ring-limit 7

The following example configures the transmission ring limit to ten particles on an ATM permanent virtual circuit (PVC) subinterface:

Router(config)# interface ATM1/0/0.1 point-to-point

Router(config-subif)# pvc 2/200

Router(config-if-atm-vc)# tx-ring-limit 10

Related Commands

Command
Description

show atm vc

Displays information about ATM PVCs and SVCs.

tx-queue-limit

Controls the number of transmit buffers available to a specified interface on the MCI and SCI cards.


vc-hold-queue

To configure the per-virtual circuit (VC) hold queue on an ATM adapter, use the vc-hold-queue interface configuration command. To return to the default value of the per-VC hold queue, use the no form of this command.

vc-hold-queue number-of-packets

no vc-hold-queue number-of-packets

Syntax Description

number-of-packets

Specifies number of packets that can be configured for the per-VC hold queue. Number of packets can be a minimum of 5 to a maximum of 1024.


Defaults

The default value of the hold queue is set by the queueing mechanism in use.

Command Modes

Interface configuration

Command History

Release
Modification

12.1(5)T

This command was introduced.


Usage Guidelines

This command can only be used on Cisco 7200 series routers and on Cisco 2600 and 3600 adapters that support per-VC queueing.

This command is configurable at the VC level only.

Examples

The following example sets the per-VC hold queue to 55:

interface atm2/0.1
 pvc 1/101
  vc-hold-queue 55

Related Commands

Command
Description

hold-queue

Specifies the hold-queue limit of an interface.

show interfaces

Displays statistics for all interfaces configured on the router or access server.

show queueing interface

Displays the queueing statistics of an interface or VC.