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Table of Contents

Frame Relay Commands

Frame Relay Commands

Use the commands described in this chapter to configure Frame Relay. Frame Relay was conceived as a protocol for use over serial interfaces and was designed for those networks with large T1 installations.

For Frame Relay configuration information and examples, refer to the "Configuring Frame Relay" chapter in the Router Products Configuration Guide.

clear frame-relay-inarp

To clear dynamically created Frame Relay maps, which are created by the use of Inverse ARP, use the clear frame-relay-inarp EXEC command.

clear frame-relay-inarp
Syntax Description

This command has no arguments or keywords.

Command Mode

EXEC

Example

The following example clears dynamically created Frame Relay maps:

clear frame-relay-inarp
Related Commands

frame-relay inverse-arp
show frame-relay map

encapsulation frame-relay

Use the encapsulation frame-relay interface configuration command to enable Frame Relay encapsulation. The no form of this command disables Frame Relay.

encapsulation frame-relay [cisco | ietf]
no encapsulation frame-relay [ietf]
Syntax Description
cisco (Optional) Uses Cisco's own encapsulation, which is a four-byte header, with two bytes to identify the DLCI and two bytes to identify the packet type. This is the default.
ietf (Optional) Sets the encapsulation method to comply with the IETF standard (RFCs 1294 and 1490). Use this keyword when connecting to another vendor's equipment across a Frame Relay network.
Default

Enabled

Command Mode

Interface configuration

Usage Guidelines

Use this command with no keywords to restore the default Cisco encapsulation.

Examples

The following example configures Cisco Frame Relay encapsulation on interface serial 1:

interface serial 1 encapsulation frame-relay

Use the ietf keyword if your router is connected to another vendor's equipment across a Frame Relay network to conform with RFCs 1294 and 1490:

interface serial 1 encapsulation frame-relay ietf

frame-relay broadcast-queue

To create a special queue for a specified interface to hold broadcast traffic that has been replicated for transmission on multiple DLCIs, use the frame-relay broadcast-queue interface configuration command.

frame-relay broadcast-queue size byte-rate packet-rate
Command Syntax
size Number of packets to be held in the broadcast queue. The default is 64 packets.
byte-rate Maximum number of bytes to be transmitted per second. The default is 256000 bytes per second.
packet-rate Maximum number of packets to be transmitted per second. The default is 36 packets per second.
Default

The default values are as follows:

size--64 packets
byte-rate--256000 bytes per second
packet-rate--36 packets per second

Command Mode

Interface configuration

Usage Guidelines

For purposes of the Frame Relay broadcast queue, broadcast traffic is defined as packets that have been replicated for transmission on multiple DLCIs, but it does not include the original routing packet or SAP packet, which passes through the normal queue. Due to timing sensitivity, bridged broadcasts and spanning tree packets are sent through the normal queue.

The Frame Relay broadcast queue is managed independently of the normal interface queue. It has its own buffers and a configurable service rate.

A broadcast queue is given a maximum transmission rate (throughput) limit measured in bytes per second and packets per second. The queue is serviced to ensure that only this maximum is provided. The broadcast queue has priority when transmitting at a rate below the configured maximum, and hence has a guaranteed minimum bandwidth allocation. The two transmission rate limits are intended to avoid flooding the interface with broadcasts. The actual limit in any second is the first rate limit that is reached.

Given the transmission rate restriction, additional buffering will be required to store broadcast packets. The broadcast queue is configurable to store large numbers of broadcast packets.

The queue size should be set to avoid loss of broadcast routing update packets. The exact size will depend on the protocol being used and the number of packets required for each update. To be safe, set the queue size so that one complete routing update from each protocol and for each DLCI can be stored. As a general rule, start with 20 packets per DLCI.

As a general rule, the byte rate should be less than both of the following:

The packet rate is not critical if you set the byte rate conservatively. As a general rule, set the packet rate assuming 250-byte packets.

Example

The following example specifies a broadcast queue to hold 80 packets, to have a maximum byte transmission rate of 240,000 bytes per second, and to have a maximum packet transmission rate of 160 packets per second:

frame-relay broadcast-queue 80 240000 160

frame-relay de-group

To specify the discard eligibility (DE) group number to be used for a specified DLCI, use the frame-relay de-group interface configuration command. To disable a previously defined group number assigned to a specified DLCI, use the no form of the command with the relevant keyword and arguments.

frame-relay de-group group-number dlci
no frame-relay de-group
[group-number] [dlci]
Syntax Description
group-number DE group number to apply to the specified DLCI number, in the range from 1 through 10.
dlci DLCI number.
Default

No DE group is defined.

Command Mode

Interface configuration

Usage Guidelines

To disable all previously defined group numbers, use the no form of this command with no arguments.

This command requires that Frame Relay software be enabled.

The DE bit is not set or recognized by the Frame Relay switching code, but must be recognized and interpreted by the Frame Relay network.

Example

The following example specifies that group number 3 will be used for DLCI 170:

frame-relay de-group 3 170
Related Command

frame-relay de-list

frame-relay de-list

To define a discard eligibility (DE) list specifying which packets will have the DE bit set and thus will be eligible for discarding when congestion is experienced on the Frame Relay switch, use the frame-relay de-list global configuration command. To delete a portion of a previously defined DE list, use the no form of this command.

frame-relay de-list list-number protocol {protocol | type number} characteristic
no frame-relay de-list list-number protocol {protocol | type number} characteristic
Syntax Description
list-number Number of the DE list.
protocol One of the following keywords corresponding to a supported protocol or device:
arp--Address Resolution Protocol.
apollo--Apollo Domain.
appletalk--AppleTalk.
bridge--bridging device.
clns--ISO Connectionless Network Service.
clns_es--CLNS end systems.
clns_is--CLNS intermediate systems.
compressedtcp--Compressed TCP.
decnet--DECnet.
decnet_node--DECnet end node.
decnet_router-L1--DECnet Level 1 (intra-area) router.
decnet_router-L2--DECnet Level 2 (interarea) router.
ip--Internet Protocol.
ipx--Novell Internet Packet Exchange.
vines--Banyan VINES.
xns--Xerox Network Systems.
type Interface type.
number Interface unit number.
characteristic You must supply one of the following:

fragments--Classify fragmented IP packets.
tcp port--TCP packets to or from a specified port.
udp port--UDP packets to or from a specified port.
list access-list-number--Previously defined access list number.
gt bytes--Packets larger than the specified number of bytes will
have the DE bit set.
lt bytes--Packets smaller than the specified number of bytes
will have the DE bit set.

Default

Discard eligibility is not defined.

Command Mode

Global configuration

Usage Guidelines

To remove an entire DE list, use the no form of this command with no options and arguments.

This prioritization feature requires that the Frame Relay network be able to interpret the DE bit as indicating which packets can be dropped first in case of congestion or which packets are less time sensitive or both.

Example

The following example specifies that IP packets larger than 512 bytes will have the discard eligibility bit set.

frame-relay de-list 1 protocol ip gt 512

frame-relay interface-dlci

Use the frame-relay interface-dlci interface configuration command to allow use of subinterfaces in the Frame Relay network. To remove this feature, use the no frame-relay interface-dlci command.

frame-relay interface-dlci dlci [option]
no frame-relay interface-dlci
dlci [option]
Syntax Description
dlci

A DLCI number to be used on the specified subinterface

option (Optional) Broadcast or encapsulation keyword, as defined in
Table 9-1

Frame Relay Subinterface Configuration Options
Keyword Option
broadcast Broadcasts should be forwarded out through this interface.
ietf IETF Frame Relay encapsulation.
cisco Cisco Frame Relay encapsulation.
Default

None

Command Mode

Interface configuration

Usage Guidelines

Subinterfaces are logical interfaces associated with a physical interface. To effectively use this command you must be in subinterface configuration mode. This requires making the logical subinterface assignment before assigning the DCLI and any encapsulation or broadcast options. See the following example.

Example

The following example assigns DLCI 100 to subinterface serial 5.17:

! Enter interface configuration and begin assignments on interface serial 5 interface serial 5 ! Enter subinterface configuration by assigning subinterface 17 interface serial 5.17 ! Now assign a DLCI number frame-relay interface-dlci 100

Use a question mark at the command parser to obtain a list of acceptable arguments, as needed.

frame-relay intf-type

Use the frame-relay intf-type interface configuration command to configure a Frame Relay switch type. Use the no frame-relay intf-type command to disable the switch.

frame-relay intf-type [dce | dte | nni]
no frame-relay intf-type [dce | dte | nni]
Syntax Description
dce (Optional) Router functions as a switch connected to a router.
dte (Optional) Router is connected to a Frame Relay network.
nni (Optional) Router functions as a switch connected to a switch (supports NNI connections).
Default

DTE

Command Mode

Interface configuration

Example

The following example configures a DTE switch type:

interface serial 2 frame-relay intf-type DTE

frame-relay inverse-arp

Use the frame-relay inverse-arp interface configuration command to enable the Inverse Address Resolution Protocol (InvARP) on the router configured for Frame Relay. Use the no frame-relay inverse-arp command to disable this feature.

frame-relay inverse-arp protocol dlci
no frame-relay inverse-arp
protocol dlci
Syntax Description
protocol Supported protocols: appletalk, decnet, ip, ipx, vines, and xns.
dlci A DLCI number used on the interface. Acceptable numbers are integers in the range 16 to 1007.
Default

Frame Relay InvARP is enabled.

Command Mode

Interface configuration

Usage Guidelines

This implementation of Inverse ARP is based on RFC 1293. It allows a router running Frame Relay to discover the protocol address of a device associated with the virtual circuit.

In Frame Relay, permanent virtual circuits are identified by a DLCI, which is the equivalent of a hardware address. By exchanging signaling messages, a network announces a new virtual circuit, and with Inverse ARP, the protocol address at the other side of the circuit can be discovered.

The show frame-relay map command displays the word "dynamic" to flag virtual circuits that are created dynamically by Inverse ARP.

Example

The following example sets Inverse ARP on an interface running AppleTalk:

interface serial 0 frame-relay inverse-arp appletalk 100
Related Commands

clear frame-relay-inarp
show frame-relay map

frame-relay ip tcp header-compression

To configure an interface to ensure that the associated PVC will always carry outgoing TCP/IP headers in compressed form, use the frame-relay ip tcp header-compression interface configuration command. To disable compression of TCP/IP packet headers on the interface, use the no form of this command.

frame-relay ip tcp header-compression [passive]
no frame-relay ip tcp header-compression
Syntax Description
passive (Optional) Compresses the outgoing TCP/IP packet header only if an incoming packet had a compressed header.
Default

Active TCP/IP header compression; all outgoing TCP/IP packets are subjected to header compression.

Command Mode

Interface configuration

Usage Guidelines

This command applies to interfaces that support Frame Relay encapsulation, specifically serial ports and HSSI.

Frame Relay must be configured on the interface before this command can be used.

TCP/IP header compression and 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 will inherit the compression characteristics of the interface, unless header compression is explicitly rejected or modified by using the frame-relay map ip header compression command.

Example

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 Command

frame-relay map ip tcp header-compression

frame-relay keepalive

To enable the Local Management Interface (LMI) mechanism for serial lines using Frame Relay encapsulation, use the frame-relay keepalive interface configuration command. Use the
no frame-relay keepalive command to disable this capability.

frame-relay keepalive number
no frame-relay keepalive
Syntax Description
number An integer that defines the keepalive interval. The interval must be set and must be less than the interval set on the switch; see the
frame-relay lmi-t392dce
command description.
Default

10 seconds

Command Mode

Interface configuration

Usage Guidelines

The frame-relay keepalive and keepalive commands perform the same function; both commands enable the keepalive sequence. The keepalive sequence is part of the Local Management Interface (LMI) protocol, so these commands also control the enabling and disabling of the LMI.

When viewing the configuration information using the show configuration command, only the keepalive command setting is included; you will not see the frame-relay keepalive setting.


Note When netbooting over Frame Relay, it might be necessary to disable keepalives.
Example

The following example sets the keepalive timer on the server for a period that is two or three seconds faster (shorter interval) than the interval set on the keepalive timer of the Frame Relay switch. The difference in keepalive intervals ensures proper synchronization between the Cisco server and the Frame Relay switch.

interface serial 3 frame-relay keepalive 8
Related Commands

A dagger (+) indicates that the command is documented in another chapter.

keepalive +
frame-relay lmi-t392dce

frame-relay lmi-n391dte

Use the frame-relay lmi-n391dte interface configuration command to set a full status polling interval. Use the no frame-relay lmi-n391dte command to restore the default interval value, assuming an LMI has been configured.

frame-relay lmi-n391dte keep-exchanges
no frame-relay lmi-n391dte
keep-exchanges
Syntax Description
keep-exchanges Number of keep exchanges to be done before requesting a full status message. Acceptable value is a positive integer in the range 1 through 255.
Default

6 keep exchanges

Command Mode

Interface configuration

Usage Guidelines

Use this command when the interface is configured as data terminal equipment (DTE) or network-to-network interface (NNI) as a means of setting the full status message polling interval.

Example

In the following example, one out of every four status inquiries generated by the router will request a full status response from the switch. The other three status inquiries will request keepalive exchanges only.

interface serial 0 frame-relay intf-type DTE frame-relay lmi-n391dte 4

frame-relay lmi-n392dce

Use the frame-relay lmi-n392dce interface configuration command to set the DCE and NNI error threshold. Use the no frame-relay lmi-n392dce command to remove the current setting.

frame-relay lmi-n392dce threshold
no frame-relay lmi-n392dce
threshold
Syntax Description
threshold Error threshold value. Acceptable value is a positive integer in the range 1 through 10.
Default

2

Command Mode

Interface configuration

Usage Guidelines

In Cisco's implementation, N392 errors must occur within the number defined by the N393 event count in order for the link to be declared down. Therefore, the threshold value for this command must be less than the count value defined in the frame-relay lmi-n393dce command.

Example

In the following example, the LMI failure threshold is set to three. The router acts as a Frame Relay DCE or NNI switch.

interface serial 0 frame-relay intf-type DCE frame-relay lmi-n392dce 3
Related Command

frame-relay lmi-n393dce

frame-relay lmi-n392dte

Use the frame-relay lmi-n392dte interface configuration command to set the error threshold on a DTE or NNI interface. Use the no frame-relay lmi-n392dte command to remove the current setting.

frame-relay lmi-n392dte threshold
no frame-relay lmi-n392dte
threshold
Syntax Description
threshold Error threshold value. Acceptable value is a positive integer in the range 1 through 10.
Default

2

Command Mode

Interface configuration

Example

In the following example, the LMI failure threshold is set to three. The router acts as a Frame Relay DTE or NNI switch.

interface serial 0 frame-relay intf-type DTE frame-relay lmi-n392dte 3

frame-relay lmi-n393dce

Use the frame-relay lmi-n393dce interface configuration command to set the DCE and NNI monitored events count. Use the no frame-relay lmi-n393dce command to remove the current setting.

frame-relay lmi-n393dce events
no frame-relay lmi-n393dce
events
Syntax Description
events Monitored events count value. Acceptable value is a positive integer in the range 1 through 10.
Default

2

Command Mode

Interface configuration

Usage Guidelines

This command and the frame-relay lmi-n392dce command define the condition that causes the link to be declared down. In Cisco's implementation, N392 errors must occur within the events count in order for the link to be declared down. Therefore, the events value defined in this command must be greater than the threshold value defined in the frame-relay lmi-n392dce command.

Example

In the following example, the LMI monitored events count is set to three. The router acts as a Frame Relay DCE or NNI switch.

interface serial 0 frame-relay intf-type DCE frame-relay lmi-n393dce 3
Related Command

frame-relay lmi-n392dce

frame-relay lmi-n393dte

Use the frame-relay lmi-n393dte interface configuration command to set the monitored event count on a DTE or NNI interface. Use the no frame-relay lmi-n393dte command to remove the current setting.

frame-relay lmi-n393dte events
no frame-relay lmi-n393dte
events
Syntax Description
events Monitored event count value. Acceptable value is a positive integer in the range 1 through 10.
Default

2

Command Mode

Interface configuration

Example

In the following example, the LMI monitored events count is set to three. The router acts as a Frame Relay DTE or NNI switch.

interface serial 0 frame-relay intf-type DTE frame-relay lmi-n393dte 3

frame-relay lmi-t392dce

Use the frame-relay lmi-t392dce interface configuration command to set the polling verification timer on a DCE or NNI interface. Use the no frame-relay lmi-t392dce command to remove the current setting.

frame-relay lmi-t392dce timer
no frame-relay lmi-t392dce
timer
Syntax Description
timer Polling verification timer value (in seconds). Acceptable value is a positive integer in the range 5 through 30.
Default

15

Command Mode

Interface configuration

Usage Guidelines

The value for the timer must be greater than the DTE or NNI keepalive timer.

Example

The following example indicates a polling verification timer on a DCE or NNI interface set to 20:

interface serial 3 frame-relay intf-type DCE frame-relay lmi-t392dce 20
Related Command

frame-relay keepalive

frame-relay lmi-type

Use the frame-relay lmi-type interface configuration command to select the Local Management Interface (LMI) type. Use the no frame-relay lmi-type command to return to the default LMI type.

frame-relay lmi-type {cisco | ansi | q933a}
no frame-relay lmi-type {ansi | q933a}
Syntax Description
cisco LMI type defined jointly by Cisco and three other companies.
ansi Annex D defined by ANSI standard T1.617
q933a International Telecommunication Union Telecommunication Standardization Sector (ITU-T) Q.933 Annex A.
Default

Cisco LMI

Command Mode

Interface configuration

Usage Guidelines

Cisco's implementation of Frame Relay supports three LMI types: Cisco, ANSI Annex D, and
ITU-T.

The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) carries out the functions of the former Consultative Committee for International Telegraph and Telephone (CCITT).

The no form of the command is included to maintain backwards compatibility. If the LMI type is changed from ANSI or ITU-T, the LMI type reverts to the Cisco type.

The LMI type is set on a per-interface basis and is shown in the output of the show interfaces EXEC command.

Example

The following is an example of the commands you enter to select the ANSI Annex D LMI type:

interface Serial1 encapsulation frame-relay frame-relay lmi-type ansi

frame-relay local-dlci

Use the frame-relay local-dlci interface configuration command to set the source DLCI for use when the LMI is not supported. Use the no frame-relay local-dlci command to remove the DLCI number.

frame-relay local-dlci number
no frame-relay local-dlci

Note The frame-relay local-dlci command is provided mainly to allow testing of the Frame Relay encapsulation in a setting where two servers are connected back to back. This command is not required in a live Frame Relay network.
Syntax Description
number Local (source) DLCI number to be used
Default

No source DLCI is set.

Command Mode

Interface configuration

Usage Guidelines

If LMI is supported and the multicast information element is present, the network server sets its local DLCI based on information provided via the LMI.

Example

The following example specifies 100 as the local DLCI:

interface serial 4 frame-relay local-dlci 100

frame-relay map

Use the frame-relay map interface configuration command to define the mapping between an address and the DLCI used to connect to the address. Use the no frame-relay map command to delete the map entry.

frame-relay map protocol protocol-address dlci [broadcast] [ietf | cisco]
no frame-relay map protocol protocol-address
Syntax Description
protocol Supported protocols: appletalk, decnet, ip, xns, ipx, and vines.
protocol-address Address for the protocol.
dlci DLCI number used to connect to the specified protocol address on the interface.
broadcast (Optional) Broadcasts should be forwarded to this address when multicast is not enabled (see the frame-relay multicast-dlci command for more information about multicasts). This keyword also simplifies the configuration of OSPF (see "Usage Guidelines" for more detail).
ietf (Optional) IETF form of Frame Relay encapsulation. Use when the router is connected to another vendor's equipment across a Frame Relay network.
cisco (Optional) Cisco encapsulation method.
Default

No mapping is defined.

Command Mode

Interface configuration

Usage Guidelines

There can be many DLCIs known by a router that can send data to many different places, but they are all multiplexed over one physical link. The Frame Relay map tells the router how to get from a specific protocol and address pair to the correct DLCI.

The optional ietf and cisco keywords allow flexibility in the configuration. If no keywords are specified in the configuration, the map inherits the attributes set with the encapsulation frame-relay command. You can also use the encapsulation options to specify that, for example, all interfaces use IETF encapsulation except one, which needs the original Cisco encapsulation method, and it can be defined using the cisco keyword with the frame-relay map command.

The broadcast keyword provides two functions: It forwards broadcasts when multicasting is not enabled, and it simplifies the configuration of OSPF for nonbroadcast networks that will use Frame Relay.

OSPF treats a nonbroadcast, multiaccess network such as Frame Relay much the same way it treats a broadcast network in that it requires selection of a designated router. In previous releases, this required manual assignment in the OSPF configuration using the neighbor interface router command. When the frame-relay map command is included in the configuration with the broadcast, and the ip ospf network command (with the broadcast keyword) is configured, there is no need to configure any neighbors manually. OSPF will now automatically run over the Frame Relay network as a broadcast network. (Refer to the ip ospf network interface command for more detail.)


Note The OSPF broadcast mechanism assumes that IP class D addresses are never used for regular traffic over Frame Relay.
Example

The following example maps IP address 131.108.123.1 to DLCI 100:

interface serial 0 frame-relay map IP 131.108.123.1 100 broadcast

OSPF will use DLCI 100 to broadcast updates.

frame-relay map bridge

Use the frame-relay map bridge interface configuration command to specify that broadcasts should be forwarded when bridging. Use the no frame-relay map bridge command to delete the map entry.

frame-relay map bridge dlci [broadcast]
no frame-relay map bridge dlci
Syntax Description
dlci DLCI number to be used for bridging on the specified interface or subinterface.
broadcast (Optional) Broadcasts should be forwarded to this address when multicast is not enabled.
Default

No broadcasts are forwarded.

Command Mode

Interface configuration

Examples

The following example uses DLCI 144 for bridging:

interface serial 0 frame-relay map bridge 144 broadcast

The following example sets up separate point-to-point links over a subinterface and runs transparent bridging over it:

interface serial 0 bridge-group 1 encapsulation frame-relay interface serial 0.1 bridge-group 1 frame-relay map bridge 42 broadcast interface serial 0.2 bridge-group 1 frame-relay map bridge 64 broadcast interface serial 0.3 bridge-group 1 frame-relay map bridge 73 broadcast

DLCI 42 is used as the link; see the section "Frame Relay Configuration Examples" in the Router Products Configuration Guide for more examples of subinterfaces.

frame-relay map clns

Use the frame-relay map clns interface configuration command to specify that broadcasts should be forwarded when routing using ISO CLNS. Use the no frame-relay map clns interface configuration command to delete the map entry.

frame-relay map clns dlci [broadcast]
no frame-relay map clns dlci
Syntax Description
dlci

DLCI number to which CLNS broadcasts should be forwarded on the specified interface.

broadcast (Optional) Broadcasts should be forwarded to this address when multicast is not enabled.
Default

No broadcasts are forwarded.

Command Mode

Interface configuration

Example

The following example uses DLCI 125 for ISO CLNS routing:

interface serial 0 frame-relay map clns 125 broadcast

frame-relay map ip tcp header-compression

To assign header compression characteristics to an IP map that differ from the compression characteristics of the interface with which the IP map is associated, use the frame-relay map ip tcp header-compression interface configuration command. To remove the IP map, use the no form of this command.

frame-relay map ip ip-address dlci [broadcast] [cisco | ietf] [nocompress]
tcp header-compression
{active | passive}
no frame-relay map ip ip-address dlci
Syntax Description
ip-address IP address.
dlci DLCI number.
broadcast (Optional) Forwards broadcasts to the specified IP address.
cisco (Optional) Uses Cisco's proprietary encapsulation. This is the default.
ietf (Optional) Uses RFC 1294 encapsulation. No TCP/IP header compression is done if IETF encapsulation is chosen for the IP map or the associated interface.
nocompress (Optional) Disables TCP/IP header compression for this map.
active Compresses the header of every outgoing TCP/IP packet.
passive Compresses the header of an outgoing TCP/IP packet only if an incoming TCP/IP packet had a compressed header.
Default

The default encapsulation is cisco.

Command Mode

Interface configuration

Usage Guidelines

To disable TCP/IP header compression on the IP map, use the nocompress form of the command.

IP maps inherit the compression characteristics of the associated interface unless this command is used to provide different characteristics. This command can also be used to reconfigure an IP map that existed before TCP header compression was configured on the associated interface.

When IP maps at both ends of a connection inherit passive compression, the connection will never transfer compressed traffic because neither side will generate a packet with a compressed header.

If you change the encapsulation characteristics of the interface to IETF, you lose the TCP header compression configuration of the associated IP map.

The command frame-relay map ip ip-address dlci tcp header-compression active can also be entered as frame-relay map ip ip-address dlci active tcp header-compression.

Example

The following example illustrates a command sequence configuring an IP map associated with serial interface 1 to enable active TCP header compression:

interface serial 1 encapsulation frame-relay ip address 131.108.177.170 255.255.255.0 frame-relay map ip 131.108.177.180 190 cisco tcp header-compression active
Related Command

frame-relay ip tcp header-compression

frame-relay multicast-dlci

Use the frame-relay multicast-dlci interface configuration command to define the DLCI to be used for multicasts. Use the no frame-relay multicast-dlci command to remove the multicast group.

frame-relay multicast-dlci number
no frame-relay multicast-dlci

Note The frame-relay multicast-dlci command is provided mainly to allow testing of the Frame Relay encapsulation in a setting where two servers are connected back to back. This command is not required in a live Frame Relay network.
Syntax Description
number Multicast DLCI. (Note that this is not the multicast group number, which is an entirely different value.)
Default

No DLCI is defined.

Command Mode

Interface configuration

Usage Guidelines

Use this command when the multicast facility is not supported. Network transmissions (packets) sent to a multicast DLCI are delivered to all network servers defined as members of the multicast group.

Example

The following example specifies 1022 as the multicast DLCI:

interface serial 0 frame-relay multicast-dlci 1022

frame-relay route

Use the frame-relay route interface configuration command to specify the static route for PVC switching. Use the no frame-relay route command to remove a static route.

frame-relay route in-dlci out-interface out-dlci
no frame-relay route
in-dlci out-interface out-dlci
Syntax Description
in-dlci DLCI on which the packet is received on the interface.
out-interface Interface the router uses to transmit the packet.
out-dlci DLCI the router uses to transmit the packet over the specified out-interface.
Default

No static route is specified.

Command Mode

Interface configuration

Examples

The following example configures a static route that allows packets in DLCI 100 and transmits packets out over DLCI 200 on interface serial 2:

frame-relay route 100 interface Serial2 200

The following example illustrates the commands you enter for a complete configuration that includes two static routes for PVC switching between interface serial 1 and interface serial 2:

interface Serial1 no ip address encapsulation frame-relay keepalive 15 frame-relay lmi-type ansi frame-relay intf-type dce frame-relay route 100 interface Serial2 200 frame-relay route 101 interface Serial2 201 clockrate 2000000

frame-relay switching

Use the frame-relay switching global configuration command to enable PVC switching on a Frame Relay DCE or an NNI. Use the no frame-relay switching command to disable switching.

frame-relay switching
no frame-relay switching
Syntax Description

This command has no arguments or keywords.

Command Mode

Global configuration

Default

Disabled

Usage Guidelines

This command must be added to the configuration file before configuring the routes.

Example

The following example shows the simple command that is entered in the configuration file before the Frame Relay configuration commands to enable switching:

frame-relay switching

show frame-relay ip tcp header-compression

To display statistics and TCP/IP header compression information for the interface, use the show frame-relay ip tcp header-compression EXEC command.

show frame-relay ip tcp header-compression
Syntax Description

This command has no arguments or keywords.

Command Mode

EXEC

Sample Display

The following is sample output from the show frame-relay ip tcp header-compression command:

DLCI 200 Link/Destination info: ip 131.108.177.200 Interface Serial0: Rcvd: 40 total, 36 compressed, 0 errors 0 dropped, 0 buffer copies, 0 buffer failures Sent: 0 total, 0 compressed 0 bytes saved, 0 bytes sent Connect: 16 rx slots, 16 tx slots, 0 long searches, 0 misses, 0% hit ratio Five minute miss rate 0 misses/sec, 0 max misses/sec

Table 9-2 describes the fields shown in the display.


Show Frame-Relay IP TCP Header-Compression Field Descriptions
Field Description
Rcvd
total Sum of compressed and uncompressed packets received.
compressed Number of compressed packets received.
errors Number of errors caused by errors in the header fields (version, total length, or IP checksum).
dropped Number of packets discarded. Seen only after line errors.
buffer copies Number of times that a new buffer was needed to put the uncompressed packet in.
buffer failures Number of times that a new buffer was needed but was not obtained.
Sent
total Sum of compressed and uncompressed packets sent.
compressed Number of compressed packets sent.
bytes saved Number of bytes reduced because of the compression.
bytes sent Actual number of bytes transmitted.
Connect
rx slots, tx slots Number of states allowed over one TCP connection. A state is recognized by a source address, a destination address, and an IP header length.
long searches Number of times that the connection ID in the incoming packet was not the same as the previous one that was processed.
misses Number of times that a matching entry was not found within the connection table and a new entry had to be entered.
hit ratio Percentage of times that a matching entry was found in the compression tables and the header was compressed.
Five minute miss rate Miss rate computed over the most recent 5 minutes and the maximum per-second miss rate during that period.

show frame-relay lmi

Use the show frame-relay lmi EXEC command to display statistics about the Local Management Interface (LMI).

show frame-relay lmi [type number]
Syntax Description
type (Optional) Interface type; serial only.
number (Optional) Interface unit number
Command Mode

EXEC

Usage Guidelines

Enter the command without arguments to obtain statistics about all Frame Relay interfaces.

Sample Displays

The following is sample output from the show frame-relay lmi command when the interface is a DTE:

Router# show frame-relay lmi LMI Statistics for interface Serial1 (Frame Relay DTE) LMI TYPE = ANSI Invalid Unnumbered info 0 Invalid Prot Disc 0 Invalid dummy Call Ref 0 Invalid Msg Type 0 Invalid Status Message 0 Invalid Lock Shift 0 Invalid Information ID 0 Invalid Report IE Len 0 Invalid Report Request 0 Invalid Keep IE Len 0 Num Status Enq. Sent 9 Num Status msgs Rcvd 0 Num Update Status Rcvd 0 Num Status Timeouts 9

The following is sample output from the show frame-relay lmi command when the interface is an NNI:

Router# show frame-relay lmi LMI Statistics for interface Serial3 (Frame Relay NNI) LMI TYPE = CISCO Invalid Unnumbered info 0 Invalid Prot Disc 0 Invalid dummy Call Ref 0 Invalid Msg Type 0 Invalid Status Message 0 Invalid Lock Shift 0 Invalid Information ID 0 Invalid Report IE Len 0 Invalid Report Request 0 Invalid Keep IE Len 0 Num Status Enq. Rcvd 11 Num Status msgs Sent 11 Num Update Status Rcvd 0 Num St Enq. Timeouts 0 Num Status Enq. Sent 10 Num Status msgs Rcvd 10 Num Update Status Sent 0 Num Status Timeouts 0

Table 9-3 describes significant fields shown in the output.


Show Frame-Relay LMI Field Descriptions
Field Description
LMI TYPE = Signaling or LMI specification: CISCO, ANSI, or ITU-T.
Invalid Unnumbered info Number of received LMI messages with invalid unnumbered information field.
Invalid Prot Disc Number of received LMI messages with invalid protocol discriminator.
Invalid dummy Call Ref Number of received LMI messages with invalid dummy call references.
Invalid Msg Type Number of received LMI messages with invalid message type.
Invalid Status Message Number of received LMI messages with invalid status message.
Invalid Lock Shift Number of received LMI messages with invalid lock shift type.
Invalid Information ID Number of received LMI messages with invalid information identifier.
Invalid Report IE Len Number of received LMI messages with invalid Report IE Length.
Invalid Report Request Number of received LMI messages with invalid Report Request.
Invalid Keep IE Len Number of received LMI messages with invalid Keep IE Length.
Num Status Enq. Rcvd Number of LMI status inquiry messages received.
Num Status msgs Sent Number of LMI status messages sent.
Num Status Update Sent Number of LMI update status messages sent.
Num Status Enq. Sent Number of LMI status inquiry messages sent.
Num Status msgs Received Number of LMI status messages received.
Num Status Update Rcvd Number of LMI update status messages received.
Num Status Timeouts Number of times the status message was not received within the keepalive timer.
Num Status Enq. Timeouts Number of times the status enquiry message was not received within the T392 DCE timer.

show frame-relay map

To display the current map entries and information about the connections, use the show frame-relay map EXEC command.

show frame-relay map
Syntax Description

This command has no arguments or keywords.

Command Mode

EXEC

Sample Display

The following is sample output from the show frame-relay map command:

Router# show frame-relay map Serial 1 (administratively down): ip 131.108.177.177 dlci 177 (0xB1,0x2C10), static, broadcast, CISCO TCP/IP Header Compression (inherited), passive (inherited)

Table 9-4 describes significant fields shown in the display.


Show Frame-Relay Map Field Descriptions
Field Description
Serial 1 (administratively down) Identifies a Frame Relay interface and its status (up or down).
ip 131.108.177.177 Destination IP address.
dlci 177 (0xB1,0x2C10) DLCI that identifies the logical connection being used to reach this interface. This value is displayed in three ways: its decimal value (177), its hexadecimal value (0xB1), and its value as it would appear on the wire (0x2C10).
static Indicates whether this is a static or dynamic entry.
CISCO Indicates the encapsulation type for this map; either CISCO or IETF.
TCP/IP Header Compression (inherited), passive (inherited) Indicates whether the TCP header compression characteristics were inherited from the interface or were explicitly configured for the IP map.
Related Command

show frame-relay pvc

show frame-relay pvc

To display statistics about PVCs for Frame Relay interfaces, use the show frame-relay pvc EXEC command.

show frame-relay pvc [type number [dlci]]
Syntax Description
type (Optional) Interface type.
number (Optional) Interface unit number.
dlci (Optional) DLCI number for the interface. Statistics for the specified PVC display when a DLCI is also specified.
Command Mode

EXEC

Usage Guidelines

To obtain statistics about PVCs on all Frame Relay interfaces, use this command with no arguments.

When the interface is configured as a pure DCE, the PVC status is determined by the status of incoming and outgoing interfaces and line status. If the outgoing interface is a tunnel, the final PVC status is determined by what is learned from the tunnel.

If the remote Frame Relay interface goes down, the status is reflected in the LMI over the tunnel. If the tunnel goes down, it is reflected by its line protocol when it does not have a route to the other end of the tunnel.

In the case of a hybrid DTE switch, the PVC status on the DTE side is determined by the PVC status learned from the external Frame Relay network.

Congestion control mechanisms are currently not supported, but the switch will pass FECN, BECN, and DE bits unchanged from ingress to egress points in the network.

Sample Display

The following is sample output from the show frame-relay pvc command:

Router# show frame-relay pvc PVC Statistics for interface Serial1 (Frame Relay DCE) DLCI = 100, DLCI USAGE = SWITCHED, PVC STATUS = ACTIVE input pkts 0 output pkts 0 in bytes 0 out bytes 0 dropped pkts 0 in FECN pkts 0 in BECN pkts 0 out FECN pkts 0 out BECN pkts 0 in DE pkts 0 out DE pkts 0 pvc create time 0:03:03 last time pvc status changed 0:03:03 Num Pkts Switched 0 DLCI = 101, DLCI USAGE = SWITCHED, PVC STATUS = INACTIVE input pkts 0 output pkts 0 in bytes 0 out bytes 0 dropped pkts 0 in FECN pkts 0 in BECN pkts 0 out FECN pkts 0 out BECN pkts 0 in DE pkts 0 out DE pkts 0 pvc create time 0:02:58 last time pvc status changed 0:02:58 Num Pkts Switched 0 DLCI = 102, DLCI USAGE = SWITCHED, PVC STATUS = DELETED input pkts 0 output pkts 0 in bytes 0 out bytes 0 dropped pkts 0 in FECN pkts 0 in BECN pkts 0 out FECN pkts 0 out BECN pkts 0 in DE pkts 0 out DE pkts 0 pvc create time 0:02:58 last time pvc status changed 0:02:58 Num Pkts Switched 0

Table 9-5 describes the fields shown in the display.


Show Frame-Relay PVC Field Descriptions
Field Description
DLCI One of the DLCI numbers associated with the PVC.
DLCI USAGE Lists SWITCHED when the router is used as a switch, or LOCAL when the router is used as a DTE.
PVC STATUS Status of the PVC: ACTIVE, INACTIVE, or DELETED.
input pkts Number of input packets.
output pkts Number of output packets.
in bytes Number of incoming bytes.
out bytes Number of outgoing bytes.
dropped pkts Number of dropped packets.
in FECN pkts Number of incoming FECN packets.
in BECN pkts Number of incoming BECN packets.
out FECN pkts Number of outgoing FECN packets.
out BECN pkts Number of outgoing BECN packets.
in DE pkts Number of incoming DE packets.
out DE pkts Number of outgoing DE packets.
pvc create time Time the PVC was created.
last time pvc status changed Time the PVC changed status (active to inactive).
Num Pkts Switched Number of switched packets seen.

show frame-relay route

Enter the show frame-relay route EXEC command at the system prompt to display all configured Frame Relay routes, along with their status.

show frame-relay route
Syntax Description

This command has no arguments or keywords.

Command Mode

EXEC

Sample Display

The following is sample output from the show frame-relay route command:

Router# show frame-relay route Input Intf Input Dlci Output Intf Output Dlci Status Serial1 100 Serial2 200 active Serial1 101 Serial2 201 active Serial1 102 Serial2 202 active Serial1 103 Serial3 203 inactive Serial2 200 Serial1 100 active Serial2 201 Serial1 101 active Serial2 202 Serial1 102 active Serial3 203 Serial1 103 inactive

Table 9-6 describes significant fields shown in the output.


Show Frame-Relay Route Field Descriptions
Field Description
Input Intf Input interface and unit.
Input Dlci Input DLCI number.
Output Intf Output interface and unit.
Output Dlci Output DLCI number.
Status Status of the connection: active or inactive.

show frame-relay traffic

Use the show frame-relay traffic EXEC command to display the router's global Frame Relay statistics since the last reload.

show frame-relay traffic
Syntax Description

This command has no arguments or keywords.

Command Mode

EXEC

Sample Display

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

Router# show frame-relay traffic Frame Relay statistics: ARP requests sent 14, ARP replies sent 0 ARP request recvd 0, ARP replies recvd 10

Information shown in the display is self-explanatory.

show interfaces serial

Use the show interfaces serial EXEC command to display information about a serial interface. When using the Frame Relay encapsulation, use the show interfaces serial command to display information on the multicast DLCI, the DLCIs defined on the interface, and the LMI DLCI used for the Local Management Interface.

The multicast DLCI and the local DLCI can be set using the frame-relay multicast-dlci and the frame-relay local-dlci commands, or provided through the Local Management Interface. The status information is taken from the LMI, when active.

show interfaces serial number
Syntax Description
number Interface number
Command Mode

EXEC

Sample Displays

The following is sample output from the show interfaces serial command for a serial interface with the CISCO LMI enabled:

Router# show interface serial 1 Serial1 is up, line protocol is down Hardware is MCI Serial Internet address is 131.108.174.48, subnet mask is 255.255.255.0 MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 246/255, load 1/255 Encapsulation FRAME-RELAY, loopback not set, keepalive set (10 sec) LMI enq sent 2, LMI stat recvd 0, LMI upd recvd 0, DTE LMI down LMI enq recvd 266, LMI stat sent 264, LMI upd sent 0 LMI DLCI 1023 LMI type is CISCO frame relay DTE Last input 0:00:04, output 0:00:02, output hang never Last clearing of "show interface" counters 0:44:32 Output queue 0/40, 0 drops; input queue 0/75, 0 drops Five minute input rate 0 bits/sec, 0 packets/sec Five minute output rate 0 bits/sec, 0 packets/sec 307 packets input, 6615 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 0 giants 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 0 input packets with dribble condition detected 266 packets output, 3810 bytes, 0 underruns 0 output errors, 0 collisions, 2 interface resets, 0 restarts 178 carrier transitions

The display shows the statistics for the LMI as the number of status inquiry messages sent (LMI sent), the number of status messages received (LMI recvd), and the number of status updates received (upd recvd). See the Frame Relay Interface specification for additional explanations of this output.

The following is sample output from the show interfaces command for a serial interface with the ANSI LMI enabled:

Router# show interface serial 1 Serial1 is up, line protocol is down Hardware is MCI Serial Internet address is 131.108.174.48, subnet mask is 255.255.255.0 MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 249/255, load 1/255 Encapsulation FRAME-RELAY, loopback not set, keepalive set (10 sec) LMI enq sent 4, LMI stat recvd 0, LMI upd recvd 0, DTE LMI down LMI enq recvd 268, LMI stat sent 264, LMI upd sent 0 LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE Last input 0:00:09, output 0:00:07, output hang never Last clearing of "show interface" counters 0:44:57 Output queue 0/40, 0 drops; input queue 0/75, 0 drops Five minute input rate 0 bits/sec, 0 packets/sec Five minute output rate 0 bits/sec, 0 packets/sec 309 packets input, 6641 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 0 giants 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 0 input packets with dribble condition detected 268 packets output, 3836 bytes, 0 underruns 0 output errors, 0 collisions, 2 interface resets, 0 restarts 180 carrier transitions

Each display provides statistics and information about the type of LMI configured, either CISCO for the Cisco LMI type, ANSI for the ANSI T1.617 Annex D LMI type, or ITU-T for the ITU-T Q.933 Annex A LMI type. See the description for the show interfaces command for a description of the other fields displayed by this command.

Related Command

A dagger (+) indicates that the command is documented in another chapter.

show interfaces+

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