Table Of Contents
Distributed Frame Relay Switching
Prerequisites for Distributed Frame Relay Switching
Restrictions for Distributed Frame Relay Switching
Information About Distributed Frame Relay Switching
Distributed Frame Relay Switching
Benefits of Distributed Frame Relay Switching
How to Configure Distributed Frame Relay Switching
Configuring the Shaping Policy for Distributed Frame Relay Switching
Configuring the Policing Policy for Distributed Frame Relay Switching
Configuring a Frame Relay Map Class for Distributed Policing, Shaping, and FRF.12 Fragmentation
Configuring Distributed Frame Relay Switching
Monitoring and Maintaining Distributed Frame Relay Switching
Configuration Examples for Distributed Frame Relay Switching
Distributed Frame Relay Switching: Example
Distributed Frame Relay Switching
The Distributed Frame Relay Switching feature allows Frame Relay switching, Modular QoS CLI (MQC) traffic shaping, MQC policing, and end-to-end FRF.12 fragmentation to occur locally on the Versatile Interface Processor (VIP) line cards, relieving the Route Switch Processor (RSP) of involvement in the switching and packet-handling processes.
Feature Specifications for Distributed Frame Relay Switching
Feature History Release Modification12.0(25)S
This feature was introduced.
Supported PlatformsCisco 7500 series
Finding Support Information for Platforms and Cisco IOS Software Images
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Contents
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Prerequisites for Distributed Frame Relay Switching
•
Restrictions for Distributed Frame Relay Switching
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Information About Distributed Frame Relay Switching
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How to Configure Distributed Frame Relay Switching
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Configuration Examples for Distributed Frame Relay Switching
Prerequisites for Distributed Frame Relay Switching
Distributed CEF must be enabled globally.
Frame Relay switching must be enabled.
Restrictions for Distributed Frame Relay Switching
Policing (configured with the police command) and shaping (configured with the shape command) are the only supported MQC features. Any attempt to configure an MQC policy map with any other feature will be rejected by the CLI.
An MQC policy map can be configured with the class-default class only. Named classes are not supported by the Distributed Frame Relay Switching feature because Layer 3 packet classification is not supported for Frame-Relay-to-Frame-Relay connections. An attempt to configure a policy map with a named class will be rejected by the CLI.
The distributed traffic shaping mechanism is restricted to a FIFO queue.
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Note
Restrictions that are specific to a particular configuration task are listed in the configuration task section.
Information About Distributed Frame Relay Switching
To configure distributed Frame Relay switching, you need to understand the following concepts:
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Distributed Frame Relay Switching
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Benefits of Distributed Frame Relay Switching
Distributed Frame Relay Switching
The Distributed Frame Relay Switching feature allows the Frame Relay switching process, which switches packets on the basis of the data-link connection identifier (DLCI), to occur locally on VIP line cards, relieving the RSP of involvement in the switching and packet-handling processes.
Distributed Frame Relay switching supports the following switching arrangements:
•
Intra-VIP switching—a pair of switched interfaces reside on the same VIP line card.
•
Inter-VIP switching—a pair of switched interfaces reside on separate VIP line cards.
•
VIP-RSP switching— one interface of a switched circuit is on a VIP line card and the other on an RSP-controlled line card.
The Distributed Frame Relay Switching feature enables the following QoS features to support distributed Frame Relay switching: MQC traffic shaping, MQC policing, and FRF.12 end-to-end fragmentation. These QoS features run on the VIP.
Benefits of Distributed Frame Relay Switching
The Distributed Frame Relay Switching feature prevents RSP performance issues by allowing Frame Relay switching processes and QoS for Frame Relay switching to be performed locally on the VIP line cards.
How to Configure Distributed Frame Relay Switching
This section contains the following tasks:
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Configuring the Shaping Policy for Distributed Frame Relay Switching (optional)
•
Configuring the Policing Policy for Distributed Frame Relay Switching (optional)
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Configuring a Frame Relay Map Class for Distributed Policing, Shaping, and FRF.12 Fragmentation (optional)
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Configuring Distributed Frame Relay Switching (required)
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Monitoring and Maintaining Distributed Frame Relay Switching (optional)
Configuring the Shaping Policy for Distributed Frame Relay Switching
Perform this task to configure the traffic-shaping policy for distributed Frame Relay switching.
Restrictions
Only the class-default class can be configured for shaping. Named classes will be rejected by the CLI.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
policy-map policy-map
4.
class class-default
5.
shape [average | peak] mean-rate [[burst-size] [excess-burst-size]]
6.
end
DETAILED STEPS
Configuring the Policing Policy for Distributed Frame Relay Switching
Perform this task to configure the traffic-policing policy for distributed Frame Relay switching.
Restrictions
Only the class-default class can be configured for policing. Named classes will be rejected by the CLI.
The conform, exceed, and violate actions of the police command are restricted to the transmit and drop options. If you do not configure conform, exceed, or violate actions, the "no action" behavior occurs.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
policy-map policy-map
4.
class class-default
5.
police bps [burst-normal] [burst-max] conform-action action exceed-action action [violate-action action]
6.
end
DETAILED STEPS
Configuring a Frame Relay Map Class for Distributed Policing, Shaping, and FRF.12 Fragmentation
Perform this task to configure the Frame Relay map class to which the policing and shaping policies will be attached.
Restrictions
Only input policing policies can be attached to a Frame Relay map class.
Only output shaping policies can be attached to a Frame Relay map class.
Only shaping and policing policies can be attached to a Frame Relay map class by using the service-policy command. A policy with anything other than shaping or policing functions (such as fair queueing) will be rejected by the CLI.
Only Frame Relay fragmentation (configured by using the fragment command) can be configured in the map class. No other Frame Relay features are supported for configuration in the map class.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
map-class frame-relay map-class-name
4.
service-policy input policy-map-name
5.
service-policy output policy-map-name
6.
frame-relay fragment fragment-size [switched]
7.
end
DETAILED STEPS
Configuring Distributed Frame Relay Switching
Perform this task to configure distributed Frame Relay switching.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
ip cef distributed
4.
frame-relay switching
5.
interface type number
6.
encapsulation frame-relay [cisco | ietf]
7.
frame-relay interface-dlci dlci switched
8.
class name
9.
exit
10.
Repeat Steps 5 through 9 for each switched PVC.
11.
connect connection-name interface dlci interface dlci
12.
end
DETAILED STEPS
Monitoring and Maintaining Distributed Frame Relay Switching
Perform this task to monitor and maintain distributed Frame Relay switching.
SUMMARY STEPS
1.
enable
2.
show frame-relay pvc
3.
debug frame-relay ipc
DETAILED STEPS
Configuration Examples for Distributed Frame Relay Switching
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Distributed Frame Relay Switching: Example
Distributed Frame Relay Switching: Example
The following example shows the configuration of Frame Relay switching with distributed shaping and policing:
policy-map out-policy-mapclass class-defaultshape average 64000policy-map in-policy-mapclass class-defaultpolice cir 128000!interface Serial0encapsulation frame-relayframe-relay interface-dlci 100 switchedclass myclass!interface Serial1encapsulation frame-relayframe-relay interface-dlci 101 switchedclass myclass!map-class frame-relay myclassservice-policy input in-policy-mapservice-policy output out-policy-map!connect connection1 Serial0 100 Serial1 101Additional References
The following references provide additional information related to distributed Frame Relay switching.
Related Documents
Standards
Standards TitleNo new or modified standards are supported. Support for existing standards has not been modified.
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MIBs
RFCs
RFCs TitleNo new or modified RFCs are supported. Support for existing RFCs has not been modified.
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Technical Assistance
Command Reference
This section documents new and modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.2 command reference publications.
debug frame-relay ipc
To display Frame Relay-specific IPC messages that are exchanged between the VIP and the RSP consoles, use the debug frame-relay ipc command in privileged EXEC mode. To stop displaying IPC messages, use the no form of this command.
debug frame-relay ipc
no debug frame-relay ipc
Syntax Description
This command has no arguments or keywords.
Defaults
No default behavior or values
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Using the debug frame-relay ipc command in privileged EXEC mode displays messages sent from the RSP to the VIP line card. Information regarding the creation, deletion, and change in status of terminated and switched Frame Relay circuits is displayed.
Examples
Debug Messages for Switched Frame Relay Connections
The following debug messages are displayed when a switched Frame Relay connection goes down:
02:47:42:IPC-FR:RP:tx UPDATE:DLCI 100 :Serial2/0/0/1:0:dFRS (DOWN)02:47:42:IPC-FR:RP:tx UPDATE:DLCI 100 :Serial2/0/1/1:0:dFRS (DOWN)The following debug messages are displayed when a switched Frame Relay connection comes up:
02:48:12:IPC-FR:RP:tx UPDATE:DLCI 100 :Serial2/0/0/1:0:dFRS (UP)02:48:12:IPC-FR:RP:tx UPDATE:DLCI 100 :Serial2/0/1/1:0:dFRS (UP)The following debug messages are displayed when a switched Frame Relay connection is deleted:
02:51:17:IPC-FR:RP:tx UPDATE:DLCI 100 :Serial2/0/0/1:0:dFRS (DOWN)02:51:17:IPC-FR:RP:tx UPDATE:DLCI 100 :Serial2/0/1/1:0:dFRS (DOWN)02:51:17:IPC-FR:RP:tx DELETE:DLCI 100 :Serial2/0/0/1:0:dFRS (DOWN)02:51:17:IPC-FR:RP:tx DELETE:DLCI 100 :Serial2/0/1/1:0:dFRS (DOWN)Debug Messages for Terminated Frame Relay Connections
The following debug message is displayed when a terminated Frame Relay connection goes down:
03:00:13:IPC-FR:RP:tx DELETE:DLCI 100 :Serial2/0/0/1:0:USAGE 1The following debug message is displayed when a terminated Frame Relay connection comes up:
02:56:33:IPC-FR:RP:tx UPDATE:DLCI 100 :Serial2/0/0/1:0:USAGE 1The following debug message is displayed when a terminated Frame Relay connection is deleted:
03:06:00:IPC-FR:RP:tx DELETE:DLCI 100 :Serial2/0/0/1:0:USAGE 1Table 1 describes the significant fields shown in the display.
show frame-relay pvc
To display statistics about PVCs for Frame Relay interfaces, use the show frame-relay pvc command in privileged EXEC mode.
show frame-relay pvc [type] [number] [dlci]
Syntax Description
Command Modes
EXEC
Command History
Usage Guidelines
Statistics Reporting
To obtain statistics about PVCs on all Frame Relay interfaces, use this command with no arguments.
Per-VC counters are not incremented at all when either autonomous or SSE switching is configured; therefore, PVC values will be inaccurate if either switching method is used.
DCE, DTE, and Logical Interfaces
When the interface is configured as a DCE and the data-link connection identifier (DLCI) usage is SWITCHED, the value displayed in the PVC STATUS field is determined by the status of outgoing interfaces (up or down) and the status of the outgoing PVC. The status of the outgoing PVC is updated in the Local Management Interface (LMI) message exchange. PVCs terminated on a DCE interface use the status of the interface to set the PVC STATUS.
In the case of a hybrid DTE switch, the PVC status on the DTE side is determined by the PVC status reported by the external Frame Relay network through the LMI.
If the outgoing interface is a tunnel, the PVC status is determined by what is learned from the tunnel.
Traffic Shaping
Congestion-control mechanisms are currently not supported on switched PVCs, but the switch passes forward explicit congestion notification (FECN) bits, backward explicit congestion notification (BECN) bits, and discard eligibility (DE) bits unchanged from entry to exit points in the network.
If an LMI status report indicates that a PVC is not active, then it is marked as inactive. A PVC is marked as deleted if it is not listed in a periodic LMI status message.
Examples
Switched PVC: Example
The following is sample output from the show frame-relay pvc command for a switched Frame Relay PVC:
Router # show frame-relay pvc 16PVC Statistics for interface POS5/0 (Frame Relay NNI)DLCI = 16, DLCI USAGE = SWITCHED, PVC STATUS = INACTIVE, INTERFACE = POS5/0LOCAL PVC STATUS = INACTIVE, NNI PVC STATUS = ACTIVEinput pkts 0 output pkts 0 in bytes 0out bytes 0 dropped pkts 100 in FECN pkts 0in BECN pkts 0 out FECN pkts 0 out BECN pkts 0in DE pkts 0 out DE pkts 0out bcast pkts 0 out bcast bytes 0switched pkts 0Detailed packet drop counters:no out intf 0 out intf down 100 no out PVC 0in PVC down 0 out PVC down 0 pkt too big 0pvc create time 00:25:32, last time pvc status changed 00:06:31Table 2 describes the fields shown in the display that are relevant to switched PVCs.
1 The LOCAL PVC STATUS and NNI PVC STATUS fields are displayed only for PVCs configured on Frame Relay NNI interface types. These fields are not displayed if the PVC is configured on DCE or DTE interface types.
2 The detailed packet drop fields are displayed for switched Frame Relay PVCs only. These fields are not displayed for terminated PVCs.
3 MTU = maximum transmission unit.
DCE Interface with Traffic Shaping: Example
The following is sample output from the show frame-relay pvc command:
Router# show frame-relay pvcPVC Statistics for interface Serial (Frame Relay DCE)DLCI = 22, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial3/1:1.1input pkts 9 output pkts 300008 in bytes 2754out bytes 161802283 dropped pkts 0 in FECN pkts 0in BECN pkts 1 out FECN pkts 0 out BECN pkts 0in DE pkts 0 out DE pkts 0outbcast pkts 0 outbcast bytes 0Shaping adapts to ForeSight in ForeSight signals 1304pvc create time 1d05h, last time pvc status changed 00:11:00If the circuit is configured for shaping to adapt to BECN, it is indicated in the display:
Shaping adapts to BECNIf traffic shaping on the circuit does not adapt to either BECN or ForeSight, nothing extra shows:
DLCI = 100, DLCI USAGE = SWITCHED, PVC STATUS = ACTIVEinput pkts 0 output pkts 0 in bytes 0out bytes 0 dropped pkts 0 in FECN pkts 0in BECN pkts 0 out FECN pkts 0 out BECN pkts 0in DE pkts 0 out DE pkts 0outbcast pkts 0 outbcast bytes 0pvc create time 0:03:03 last time pvc status changed 0:03:03Num Pkts Switched 0Multipoint Subinterfaces: Example
The following is sample output from the show frame-relay pvc command for multipoint subinterfaces. The output displays both the subinterface number and the DLCI. This display is the same whether the PVC is configured for static or dynamic addressing.
DLCI = 300, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial0.103input pkts 10 output pkts 7 in bytes 6222out bytes 6034 dropped pkts 0 in FECN pkts 0in BECN pkts 0 out FECN pkts 0 out BECN pkts 0in DE pkts 0 out DE pkts 0outbcast pkts 0 outbcast bytes 0pvc create time 0:13:11 last time pvc status changed 0:11:46DLCI = 400, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial0.104input pkts 20 output pkts 8 in bytes 5624out bytes 5222 dropped pkts 0 in FECN pkts 0in BECN pkts 0 out FECN pkts 0 out BECN pkts 0in DE pkts 0 out DE pkts 0outbcast pkts 0 outbcast bytes 0pvc create time 0:03:57 last time pvc status changed 0:03:48Table 3 describes the fields shown in the displays.
1 DLCI = data-link connection identifier.
DTE Interface Without Traffic Shaping: Example
The following is sample output from the show frame-relay pvc command with no traffic shaping configured on the interface.
Router# show frame-relay pvcPVC Statistics for interface Serial1 (Frame Relay DTE)DLCI = 100, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial1input pkts 0 output pkts 0 in bytes 0out bytes 0 dropped pkts 0 in FECN pkts 0in BECN pkts 0 out FECN pkts 0 out BECN pkts 0in DE pkts 0 out DE pkts 0out bcast pkts 0 out bcast bytes 0DTE Interface With Traffic Shaping: Example
The following is sample output from the show frame-relay pvc command when traffic shaping is in effect:
Router# show frame-relay pvcPVC Statistics for interface Serial1 (Frame Relay DTE)DLCI = 101, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial1input pkts 14046 output pkts 4339 in bytes 960362out bytes 675566 dropped pkts 0 in FECN pkts 0in BECN pkts 148 out FECN pkts 0 out BECN pkts 0in DE pkts 44 out DE pkts 0out bcast pkts 4034 out bcast bytes 427346pvc create time 11:59:29, last time pvc status changed 11:59:29CIR 64000 BC 8000 BE 1600 limit 2000 interval 125mincir 32000 byte incremen 500 BECN response yespkts 9776 bytes 838676 pkts delayed 0 bytes delayed 0shaping inactiveList Queue Args1 4 byte-count 100Output queues: (queue #: size/max/drops)0: 0/20/0 1: 0/20/0 2: 0/20/0 3: 0/20/0 4: 0/20/05: 0/20/0 6: 0/20/0 7: 0/20/0 8: 0/20/0 9: 0/20/010: 0/20/0 11: 0/20/0 12: 0/20/0 13: 0/20/0 14: 0/20/015: 0/20/0 16: 0/20/0Table 4 describes the additional fields shown in the display when traffic shaping is in effect.
1 CIR = committed information rate.
2 Bc = committed burst size.
3 Be = excess burst size.
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