Table Of Contents
Interface Commands
This chapter describes the commands that can be used on different types of interfaces. These commands correspond to the interface configuration tasks included in the Cisco IOS configuration guides. Refer to the configuration guide indicated here for configuration guidelines:
For hardware technical descriptions, and for information about installing the router or access server interfaces, refer to the hardware installation and maintenance publication for your particular product.
Note
In Cisco IOS Release 11.3, all commands supported on the Cisco 7500 series are also supported on the Cisco 7000 series.
access-list (standard)
Use the access-list global configuration command to establish MAC address access lists. Use the no form of this command to remove a single access list entry.
access-list access-list-number {permit | deny} address mask
no access-list access-list-numberSyntax Description
Default
No MAC address access lists are established.
Command Mode
Global configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Related Commands
You can use the master indexes or search online to find documentation of related commands.
access-list (type-code)
access-list (type-code)
Use the access-list global configuration command to build type-code access lists. Use the no form of this command to remove a single access list entry.
access-list access-list-number {permit | deny} type-code wild-mask
no access-list access-list-numberSyntax Description
Default
No type-code access lists are built.
Command Mode
Global configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Type-code access lists can have an impact on system performance; therefore, keep the lists as short as possible and use wildcard bit masks whenever possible.
Access lists are evaluated according to the following algorithm:
•
•
If the length/type field is greater than 1500, the packet is treated as an LSAP packet unless the DSAP and SSAP fields are AAAA. If the latter is true, the packet is treated using type-code filtering.
If you have both Ethernet Type II and LSAP packets on your network, you should set up access lists for both.
Use the last item of an access list to specify a default action; for example, permit everything else or deny everything else. If nothing else in the access list matches, the default action is normally to deny access; that is, filter out all other type codes.
Related Commands
You can use the master indexes or search online to find documentation of related commands.
access-list (extended)
access-list (standard)auto-polarity
To enable automatic receiver polarity reversal on a hub port connected to an Ethernet interface of a Cisco 2505 or Cisco 2507, use the auto-polarity hub configuration command. To disable this feature, use the no form of this command.
auto-polarity
no auto-polaritySyntax Description
This command has no arguments or keywords.
Default
Enabled
Command Mode
Hub configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
This command applies to a port on an Ethernet hub only.
Example
The following example enables automatic receiver polarity reversal on hub 0, ports 1 through 3:
hub ethernet 0 1 3auto-polarityRelated Commands
You can use the master indexes or search online to find documentation of related commands.
hub
bandwidth
To set a bandwidth value for an interface, use the bandwidth interface configuration command. Use the no form of this command to restore the default values.
bandwidth kilobits
no bandwidthSyntax Description
kilobits
Intended bandwidth in kilobits per second. For a full bandwidth DS3, enter the value 44736.
Default
Default bandwidth values are set during startup and can be displayed with the EXEC command show interfaces.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
The bandwidth command sets an informational parameter only; you cannot adjust the actual bandwidth of an interface with this command. For some media, such as Ethernet, the bandwidth is fixed; for other media, such as serial lines, you can change the actual bandwidth by adjusting hardware. For both classes of media, you can use the bandwidth configuration command to communicate the current bandwidth to the higher-level protocols.
IGRP uses the minimum path bandwidth to determine a routing metric. The TCP protocol adjusts initial retransmission parameters based on the apparent bandwidth of the outgoing interface.
At higher bandwidths, the value you configure with the bandwidth command is not what is displayed by the show interface command. The value shown is that used in IGRP updates and also used in computing load.
Note
Example
The following example sets the full bandwidth for DS3 transmissions:
interface serial 0 bandwidth 44736Related Commands
You can use the master indexes or search online to find documentation of related commands.
vines metric
cablelength
To specify the distance of the cable from the Channelized T3 Interface Processor (CT3IP) in Cisco 7500 series routers to the network equipment, use the cablelength controller configuration command. Use the no form of this command to restore the default cable length.
cablelength feet
no cablelengthSyntax Description
Default
224 feet
Command Mode
Controller configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3.
If you do not specify the cablelength command, the default cable length of 224 feet is used by the CT3IP.
Note
Example
In the following example, the cable length for the CT3IP is set to 300:
controller t3 9/0/0cablelength 300cablelength long
To increase the pulse of a signal at the receiver and decrease the pulse from the transmitter using pulse equalization and line build-out for a T1 cable on an AS5200, use the cablelength long interface configuration command. To return the pulse equalization and line build-out values to their default settings, use the no form of this command.
cablelength long {dbgain-value dbloss-value}
no cablelength longSyntax Description
Default
Long cable length, receiver gain of 36 dB, and transmitter loss of 0 dB.
Command Mode
Interface configuration
Usage Guidelines
Use this command for configuring the controller T1 interface on the AS5200 access server.
A pulse equalizer regenerates a signal that has been attenuated and filtered by a cable loss. Pulse equalization does not produce a simple gain, but it filters the signal to compensate for complex cable loss. A gain26 receiver gain compensates for a long cable length equivalent to 26 dB of loss, while a gain36 compensates for 36 dB of loss.
The lengthening or building out of a line is used to control far-end crosstalk. Line build-out attenuates the stronger signal from the customer installation transmitter so that the transmitting and receiving signals have similar amplitudes. A signal difference of less than 7.5 dB is ideal. Line build-out does not produce simple flat loss (also known as resistive flat loss). Instead, it simulates a cable loss of 7.5 dB, 15 dB, or 22.5 dB so that the resulting signal is handled properly by the receiving equalizer at the other end.
Example
The following example increases the receiver gain by 26 decibels and decreases the transmitting pulse by 7.5 decibels for a long cable:
AS5200(config)# controller t1 0AS5200(config-controller)# cablelength long gain26 -7.5dbcas-group
To configure channelized T1 timeslots with channel associated signaling (also known as robbed bit signaling), which enables an AS5200 modem to answer and send an analog call, use the cas-group controller configuration command. Use the no form of this command to disable channel associated signaling for one or more timeslots.
cas-group channel-number [timeslots range]
no cas-group channel-number [timeslots range]Syntax Description
Default
Disabled
Command Mode
Controller configuration
Usage Guidelines
Use this command to enable an AS5200 modem to receive and send incoming and outgoing analog calls through each T1 controller that is configured for a channelized T1 line, which has 24 possible channels.
Switched 56 digital calls are not supported under this new feature.
Example
The following example shows you how to configure all 24 channels to support robbed bit signaling on a Cisco AS5200:
AS5200(config)# controller T1 0AS5200(config-controller)# cas-group 1 timeslots 1-24AS5200(config-controller)#%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 1 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 2 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 3 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 4 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 5 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 6 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 7 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 8 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 9 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 10 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 11 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 12 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 13 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 14 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 15 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 16 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 17 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 18 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 19 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 20 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 21 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 22 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 23 is up%DSX0-5-RBSLINEUP: RBS of controller 1 timeslot 24 is upchannel-group
Use the channel-group controller configuration command to define the timeslots that belong to each T1 or E1 circuit.
channel-group number timeslots range [speed {48 | 56 | 64}]
Syntax Description
Default
The default line speed when configuring a T1 controller is 56 kbps.
The default line speed when configuring an E1 controller is 64 kbps.
Command Mode
Controller configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Use this command in configurations where the router or access server must communicate with a T1 or E1 fractional data line. The channel-group number may be arbitrarily assigned and must be unique for the controller. The timeslot range must match the timeslots assigned to the channel group. The service provider defines the timeslots that comprise a channel group.
Example
In the following example, three channel groups are defined. Channel-group 0 consists of a single timeslot, channel-group 8 consists of seven timeslots and runs at a speed of 64 kbps per timeslot, and channel-group 12 consists of a single timeslot.
channel-group 0 timeslots 1channel-group 8 timeslots 5,7,12-15,20 speed 64channel-group 12 timeslots 2Related Commands
You can use the master indexes or search online to find documentation of related commands.
framing
linecodeclear controller lex
To reboot the LAN Extender chassis and restart its operating software, use the clear controller lex privileged EXEC command.
clear controller lex number [prom]
clear controller lex slot/port [prom] (for Cisco 7500 series routers
clear controller lex [type slot/port] (Cisco 7200 series and for the Cisco 7500 series
with a Packet over SONET Interface Processor)
clear controller lex [type slot/port-adapter/port] (for Cisco 7500 series with ports on VIP cards)Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
The clear controller lex command halts operation of the LAN Extender and performs a cold restart.
Without the prom keyword, if an image exists in Flash memory, and that image has a newer software version than the PROM image, and that image has a valid checksum, then this command runs the Flash image. If any one of these three conditions is not met, this command reloads the PROM image.
With the prom keyword, this command reloads the PROM image, regardless of any Flash image.
Examples
The following example halts operation of the LAN Extender bound to LAN Extender interface 2 and causes the LAN Extender to perform a cold restart from Flash memory:
Router# clear controller lex 2reload remote lex controller? [confirm] yesThe following example halts operation of the LAN Extender bound to LAN Extender interface 2 and causes the LAN Extender to perform a cold restart from PROM:
Router# clear controller lex 2 promreload remote lex controller? [confirm] yesclear counters
To clear the interface counters, use the clear counters EXEC command.
clear counters [type number]
clear counters [type slot/port] [ethernet | serial] (for the Cisco 4000 series or Cisco 7500 series
routers and a LAN Extender interface)
clear counters [type slot/port] (for Cisco 7200 series, and for the Cisco 7500 with a Packet
over SONET Interface Processor)
clear counters [type slot/port-adapter/port] (for Cisco 7500 series with ports on VIP cards)Syntax Description
Command Mode
EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command was modified in Cisco IOS Release 11.3 to include the vg-anylan interface type keyword and to change the posi keyword to pos.
This command clears all the current interface counters from the interface unless the optional arguments type and number are specified to clear only a specific interface type (serial, Ethernet, Token Ring, and so on). lists the command keywords and their descriptions.
Note
Table 24 Clear Counters Interface Type Keywords
Examples
The following example clears all interface counters:
clear countersThe following example clears the Packet OC-3 interface counters on a POSIP card in slot 1 on a Cisco 7500 series router:
clear counters pos 1/0The following example clears interface counters on the serial interface residing on a Cisco 1000 series LAN Extender:
clear counters lex 0 serialRelated Commands
You can use the master indexes or search online to find documentation of related commands.
show interfaces
clear hub
Use the clear hub EXEC command to reset and reinitialize the hub hardware connected to an interface of a Cisco 2505 or 2507 routers.
clear hub ethernet number
ethernet
Indicates the hub in front of an Ethernet interface.
number
Hub number to clear, starting with 0. Since there is currently only one hub, this number is 0.
Syntax Description
Command Mode
EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
Example
The following example clears hub 0:
clear hub ethernet 0Related Commands
You can use the master indexes or search online to find documentation of related commands.
hub
clear hub counters
Use the clear hub counters EXEC command to set to zero the hub counters on an interface of a Cisco 2505 or 2507 routers.
clear hub counters [ether number [port [end-port]]]
Syntax Description
Command Mode
EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
Example
The following example clears the counters displayed in a show hub command for all ports on hub 0:
clear hub counters ether 0Related Commands
You can use the master indexes or search online to find documentation of related commands.
show hub
clear interface
Use the clear interface EXEC command to reset the hardware logic on an interface.
clear interface type number
clear interface type slot/port (Cisco 7200, and 7500 series routers with a
Packet OC-3 Interface Processor)
clear interface [type slot/port-adapter/port] (ports on VIP cards in 7500 series routers)
clear interface type slot/port [:channel-group] (Cisco 7500 series routers
clear interface type slot/port-adapter/port [:t1-channel] (CT3IP in Cisco 7500 series routers)Syntax Description
Command Mode
EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command was modified in Cisco IOS Release 11.3 to include the vg-anylan interface type keyword and to change the posi keyword to pos.
Under normal circumstances, you do not need to clear the hardware logic on interfaces.
This command clears all the current interface hardware logic unless the optional arguments type and number are specified to clear only a specific interface type (serial, Ethernet, Token Ring, and so on). lists the command keywords and their descriptions.
Table 25
Clear Interface Type Keywords
Examples
The following example resets the interface logic on HSSI interface 1:
clear interface hssi 1The following example resets the interface logic on Packet OC-3 interface 0 on the POSIP in slot 1:
clear interface pos 1/0The following example resets the interface logic on T1 0 on the CT3IP in slot 9:
clear interface serial 9/0/0:0clear interface fastethernet
Use the clear interface fastethernet privileged EXEC command to reset the controller for a specified Fast Ethernet interface.
clear interface fastethernet number (Cisco 4500 and 4700 series routers)
clear interface fastethernet slot/port (Cisco 7200 and Cisco 7500 series routers)
clear interface fastethernet slot/port-adapter/port (Cisco 7500 series routers)Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 11.2.
Examples
The following example resets the controller for the Ethernet 0 interface on a Cisco 4500:
clear interface fastethernet 0The following example resets the controller for the Ethernet interface located in slot 1 port 0 on a Cisco 7200 or Cisco 7500:
clear interface fastethernet 1/0The following example resets the controller for the Ethernet interface located in slot 1 port adapter 0 port 0 on a Cisco 7500:
clear interface fastethernet 1/0/0clear rif-cache
Use the clear rif-cache EXEC command to clear entries from the Routing Information Field (RIF) cache.
clear rif-cache
Syntax Description
This command has no arguments or keywords.
Command Mode
EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Example
The following example clears the RIF cache:
clear rif-cacheRelated Commands
You can use the master indexes or search online to find documentation of related commands.
multiring
clear service-module serial
Use the clear service-module serial privileged EXEC configuration command to reset an integrated CSU/DSU.
clear service-module serial number
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 11.2.
Use this command only in severe circumstances (for example, when the router is not responding to a CSU/DSU configuration command).
This command terminates all DTE and line loopbacks that are locally or remotely configured. It also interrupts data transmission through the router for up to 15 seconds. The software performs an automatic software reset in case of two consecutive configuration failures.
The CSU/DSU module is not reset with the clear interface command.
CautionIf you experience technical difficulties with your router and intend to contact customer support, refrain from using this command. This command erases the router's past CSU/DSU performance statistics. To clear only the CSU/DSU performance statistics, issue the clear counters command.
Example
The following example resets the CSU/DSU on a router:
router# clear service-module serial 0router#Related Commands
You can use the master indexes or search online to find documentation of related commands.
clear counters
test service-moduleclock rate
Use the clock rate interface configuration command to configure the clock rate for the hardware connections on serial interfaces such as network interface modules (NIMs) and interface processors to an acceptable bit rate. Use the no form of this command to remove the clock rate if you change the interface from a DCE to a DTE device. Using the no form of this command on a DCE interface sets the clock rate to the hardware-dependent default value.
clock rate bps
no clock rateSyntax Description
Default
No clock rate is configured.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command was modified in Cisco IOS Release 11.3 to include nonstandard clock rates for the PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+ synchronous serial port adapters.
Cable Length
Be aware that the fastest speeds might not work if your cable is too long, and that speeds faster than 148,000 bits per second are too fast for EIA/TIA-232 signaling. It is recommended that you only use the synchronous serial EIA/TIA-232 signal at speeds up to 64,000 bits per second. To permit a faster speed, use EIA/TIA-449 or V.35.
Synchronous Serial Port Adapters
For the synchronous serial port adapters (PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+) on Cisco 7200 series routers, and on second-generation Versatile Interface Processors (VIP2s) in Cisco 7500 series routers, the clock rate you enter is rounded (if needed) to the nearest value that your hardware can support. To display the clock rate value for the port adapter, use the show running-configuration command.
If you plan to netboot your router over a synchronous serial port adapter interface and have a boot image prior to Cisco IOS Release 11.1(9)CA that does not support nonstandard (rounded) clock rates for the port adapters, you must use one of the following standard clock rates:
1200, 2400, 4800, 9600, 19200, 38400, 56000, 64000
Examples
The following example sets the clock rate on the first serial interface to 64,000 bits per second:
interface serial 0clock rate 64000The following example sets the clock rate on a synchronous serial port adapter in slot 5, port 0 to 1234567. In this example, the clock rate is adjusted to 1151526 bps.
interface serial 5/0clock rate 1234567%Clockrate rounded to nearest value that your hardware can support.%Use Exec Command `show running-config' to see the value rounded to.The following example configures serial interface 5/0 with a clock rate that is rounded to the nearest value that is supported by the hardware:
Router# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)# interface serial 5/0Router(config-if)# clock rate 1234567%Clockrate rounded to nearest value that your hardware can support.%Use Exec Command `show running-config' to see the value rounded to.Router(config-if)# exitRouter(config)#The following example shows how to determine the exact clock rate that the serial interface was rounded to using the show running-config command. This example shows only the relevant information displayed by the show running-config command; other information was omitted.
Router# show running-configBuilding configuration......!interface Serial5/0no ip addressclockrate 1151526!...clock source
Use the clock source controller configuration command to specify where the clock source is obtained for use by the Channelized T3 Interface Processor (CT3IP) in Cisco 7500 series routers. Use the no form of this command to restore the default clock source.
clock source {internal | line}
no clock sourceSyntax Description
internal
Specifies that the internal clock source is used. This is the default.
line
Specifies that the network clock source is used.
Default
internal
Command Mode
Controller configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3.
If you do not specify the clock source command, the default clock source of internal is used by the CT3IP.
You can also set the clock source for each T1 channel by using the t1 clock source controller configuration command.
Example
In the following example, the clock source for the CT3IP is set to line:
controller t3 9/0/0clock source lineRelated Commands
You can use the master indexes or search online to find documentation of related commands.
interface ethernet 2 squelch reduced
clock source (Cisco AS5200)
Use the clock source interface configuration command to select the clock source for the time-division multiplexing (TDM) bus in a Cisco AS5200 access server. The no form of this command configures the clock source to its default setting.
clock source {line {primary | secondary} | internal}
no clock source line {primary | secondary}Syntax Description
Defaults
Primary TDM clock source from the T1 0 controller
Secondary TDM clock source from the T1 1 controller
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.2.
To use the clocking coming in from a T1 line, configure the clock source line primary command on the T1 interface that has the most reliable clocking. Configure the clock source line secondary command on the T1 interface that has the next best known clocking. With this configuration, the primary line clocking is backed up to the secondary line if the primary clocking shuts down.
Example
The following example configures the Cisco AS5200 access server to use T1 controller 0 as the primary clock source and T1 controller 1 as the secondary clock source:
controller t1 0clock source line primarycontroller t1 1clock source line secondaryclock source (controller)
Use the clock source controller configuration command to set the T1-line clock-source for the MIP in the Cisco 7200 series and Cisco 7500 series or for the NPM in the Cisco 4000 series.
clock source {line | internal}
Syntax Description
line
Specifies the T1 line as the clock source.
internal
Specifies the MIP (Cisco 7200 series and Cisco 7500 series) or the NPM (Cisco 4000) as the clock source.
Defaults
Primary TDM clock source from the T0 controller
Secondary TDM clock source from the T1 controller
Command Mode
Controller configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
To use the clocking coming in from a T1 line, configure the clock source line primary command on the controller that has the most reliable clocking. Configure the clock source line secondary command on the controller that has the next best known clocking. With this configuration, the primary line clocking is backed up to the secondary line if the primary clocking shuts down.
Example
The following example configures the Cisco AS5200 to use the T0 controller as the primary clocking source and the
T1 controller as the secondary clocking source:
AS5200(config)# controller t1 0AS5200(config-if)# clock source line primaryAS5200(config-if)# exitAS5200(config)# controller t1 1AS5200(config-if)# clock source line secondaryRelated Commands
You can use the master index or search online for documentation of these and other commands.
framing
linecodeclock source (interface)
Use the clock source interface configuration command to control which clock a G.703 E1 interface will use to clock its transmitted data from. The no form of this command restores the default value.
clock source {line | internal}
no clock sourceSyntax Description
Default
By default, the applique uses the line's receive data stream.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
This command applies to a Cisco 4000 router or Cisco 7500 series router. A G.703-E1 interface
can clock its transmitted data from either its internal clock or from a clock recovered from the line's receive data stream.
Example
The following example specifies the G.703-E1 interface to clock its transmitted data from its internal clock:
clock source internalclock source (interface)
To control which clock a G.703-E1 interface will use to clock its transmitted data from, use the clock source interface configuration command. The no form of this command restores the default value.
clock source {line | internal}
no clock sourceclock source {line {primary | secondary} | internal} (Cisco AS5200 only)
no clock source line {primary | secondary}Syntax Description
Default
By default, the applique uses the line's receive data stream.
Primary TDM clock source from the T0 controller on the Cisco AS5200.
Secondary TDM clock source from the T1 controller on the Cisco AS5200.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
On the Cisco 4000 router and Cisco 7500 series router, a G.703-E1 interface can clock its transmitted data from either its internal clock or from a clock recovered from the line's receive data stream.
To use the clocking coming in from a T1 line for the Cisco AS5200, configure the clock source line primary command on the controller that has the most reliable clocking. Configure the clock source line secondary command on the controller that has the next best known clocking. With this configuration, the primary line clocking is backed up to the secondary line if the primary clocking shuts down.
Example
The following example specifies the G.703-E1 interface to clock its transmitted data from its internal clock:
clock source internalThe following example configures the Cisco AS5200 to use the T0 controller as the primary clocking source and the T1 controller as the secondary clocking source:
AS5200(config)# controller t1 0AS5200(config-if)# clock source line primaryAS5200(config-if)# exitAS5200(config)# controller t1 1AS5200(config-if)# clock source line secondarycmt connect
Use the cmt connect EXEC command to start the processes that perform the connection management (CMT) function and allow the ring on one fiber to be started.
cmt connect [interface-name [phy-a | phy-b]]
Syntax Description
interface-name
(Optional) Specifies the FDDI interface.
phy-a
(Optional) Selects Physical Sublayer A.
phy-b
(Optional) Selects Physical Sublayer B.
Command Mode
EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
In normal operation, the FDDI interface is operational once the interface is connected and configured. The cmt connect command allows the operator to start the processes that perform the CMT function.
The cmt connect command is not needed in the normal operation of FDDI; this command is used mainly in interoperability tests.
Examples
The following examples demonstrate use of the cmt connect command for starting the CMT processes on the FDDI ring.
The following command starts all FDDI interfaces:
cmt connectThe following command starts both fibers on the FDDI interface unit 0:
cmt connect fddi 0The following command on the Cisco 7200 series or Cisco 7500 series starts both fibers on the FDDI interface unit 0:
cmt connect fddi 1/0The following command starts only Physical Sublayer A on the FDDI interface unit 0:
cmt connect fddi 0 phy-aThe following command on Cisco 7500 series routers starts only Physical Sublayer A on the FDDI interface unit 0:
cmt connect fddi 1/0 phy-acmt disconnect
Use the cmt disconnect EXEC command to stop the processes that perform the connection management (CMT) function and allow the ring on one fiber to be stopped.
cmt disconnect [interface-name [phy-a | phy-b]]
Syntax Description
interface-name
(Optional) Specifies the FDDI interface.
phy-a
(Optional) Selects Physical Sublayer A.
phy-b
(Optional) Selects Physical Sublayer B.
Command Mode
EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
In normal operation, the FDDI interface is operational once the interface is connected and configured, and is turned off using the shutdown interface configuration command. The cmt disconnect command allows the operator to stop the processes that perform the CMT function and allow the ring on one fiber to be stopped.
The cmt disconnect command is not needed in the normal operation of FDDI; this command is used mainly in interoperability tests.
Examples
The following examples demonstrate use of the cmt disconnect command for stopping the CMT processes on the FDDI ring.
The following command stops all FDDI interfaces:
cmt disconnectThe following command stops both fibers on the FDDI interface unit 0:
cmt disconnect fddi 0The following command on the Cisco 7200 series or Cisco 7500 series stops both fibers on the FDDI interface unit zero:
cmt disconnect fddi 1/0The following command stops only Physical Sublayer A on the FDDI interface unit 0. This command causes the FDDI media to go into a wrapped state so that the ring will be broken.
cmt disconnect fddi 0 phy-aThe following command on the Cisco 7500 series stops only Physical Sublayer A on the FDDI interface unit 0 in slot 1. This command causes the FDDI media to go into a wrapped state so that the ring will be broken.
cmt disconnect fddi 1/0 phy-acompress
To configure compression for Link Access Procedure, Balanced (LAPB), Point-to-Point Protocol (PPP), and High-Level Data Link Control (HDLC) encapsulations, use the compress interface configuration command. On Cisco 7200 series routers and Cisco 7500 series routers, hardware compression on the compression service adapter (CSA) is supported for PPP links. To disable compression, use the no form of this command.
compress {predictor | stac}
no compress {predictor | stac}compress {predictor | stac [distributed | software]}
compress {predictor | stac [csa slot | software]} (Cisco 7200 series)Syntax Description
Default
Compression is disabled.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0 (as compress predictor). The command compress {predictor | stac} first appeared in Cisco IOS Release 10.3.
This command was modified in Cisco IOS Release 11.3 P to include the distributed, software, and csa keywords.
Using CSA hardware compression on Cisco 7200 series routers and Cisco 7500 series routers removes the compression and decompression responsibilities from the VIP2 or the main processor installed in the router. By using the compress stac command, the router determines the fastest compression method available on the router.
When using hardware compression on Cisco 7200 series routers with multiple CSAs, you can optionally specify which CSA is used by the interface to perform compression. If no CSA is specified, the router determines which CSA is used. On Cisco 7500 series routers, the router uses the CSA on the same VIP2 as the interface.
You can configure point-to-point software compression for all LAPB, PPP, and HDLC encapsulations. Compression reduces the size of frames via lossless data compression. HDLC encapsulations supports the Stacker compression algorithm. PPP and LAPB encapsulations support both predictor and Stacker compression algorithms.
When compression is performed in software installed in the router's main processor, it might significantly affect system performance. We recommend that you disable compression if the CPU load exceeds 40 percent. To display the CPU load, use the show process cpu EXEC command.
Compression requires that both ends of the serial link be configured to use compression.
If the majority of your traffic is already compressed files, we recommend that you not use compression. If the files are already compressed, the additional processing time spent in attempting unsuccessfully to compress them again will slow system performance.
provides general guidelines for deciding which compression type to select.
Software compression makes heavy demands on the router's processor. The maximum compressed serial line rate depends on the type of Cisco router you are using and which compression algorithm you specify. shows a summary of the compressed serial line rates for software compression. The maximums shown in apply to the "combined" serial compressed load on the router. For example, a Cisco 4000 series router could handle four 64-kbps lines using Stacker or one 256-kbps line. These maximums also assume there is very little processor load on the router aside from compression. Lower these numbers when the router is required to do other processor-intensive tasks.
Hardware compression can support a combined line rate of 16Mbps.
Cisco recommends that you do not adjust the maximum transmission unit (MTU) for the serial interface and the LAPB maximum bits per frame (N1) parameter.
Note
Examples
The following example enables hardware compression and PPP encapsulation on serial interface 3/1/0.
interface serial 3/1/0encapsulate pppcompress stacThe following example enables predictor compression on serial interface 0 for a LAPB link:
interface serial 0encapsulation lapbcompress predictorRelated Commands
You can use the master indexes or search online to find documentation of related commands.
encapsulation lapb
encapsulation ppp
encapsulation x25
ppp compress
show compress
show processescontroller t3
To configure the Channelized T3 Interface Processor (CT3IP) in Cisco 7500 series routers, use the controller t3 global configuration command.
controller t3 slot/port-adapter/port
Syntax Description
Default
No T3 controller is configured.
Command Mode
Global configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3.
This command is used to configure the CT3IP and the 28 T1 channels. After the T1 channels are configured, continue to configure each T1 channel as a serial interface by using the interface serial global configuration command.
Example
In the following example, the CT3IP in slot 3 is configured:
controller t3 3/0/0Related Commands
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interface serial
copy flash lex
To download an executable image from Flash memory on the core router to the LAN Extender chassis, use the copy flash lex privileged EXEC command.
copy flash lex number
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
If you attempt to download a version of the software older than what is currently running on the LAN Extender, a warning message is displayed.
Example
The following example copies the executable image namexx to the LAN Extender interface 0:
Router# copy flash lex 0Name of file to copy? namexxAddress of remote host [255.255.255.255] <cr>writing namexx !!!!!!!!!!!!!!!!!!!!!!!!!copy completeRelated Commands
You can use the master indexes or search online to find documentation of related commands.
copy tftp lex
copy tftp lex
To download an executable image from a TFTP server to the LAN Extender, use the copy tftp lex privileged EXEC command.
copy tftp lex number
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
If you attempt to download a version of the software older than what is currently running on the LAN Extender, a warning message is displayed.
Example
The following example copies the file namexx from the TFTP server:
Router# copy tftp lex 0Address or name of remote host (255.255.255.255]? 131.108.1.111Name of file to copy? namexxOK to overwrite software version 1.0 with 1.1 ?[confirm]Loading namexx from 131.108.13.111!!!!!!!!!!!!!!!!!!!!!!!!![OK - 127825/131072 bytes]Successful download to LAN Extendercrc
To set the length of the cyclic redundancy check (CRC) on a Fast Serial Interface Processor (FSIP) or HSSI Interface Processor (HIP) of the Cisco 7500 series routers or on a 4-port serial adapter of the Cisco 7200 series routers, use the crc interface configuration command. To set the CRC length to 16 bits, use the no form of this command.
crc size
no crcSyntax Description
Default
16 bits
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
All interfaces use a 16-bit cyclic redundancy check (CRC) by default, but also support a 32-bit CRC. CRC is an error-checking technique that uses a calculated numeric value to detect errors in transmitted data. The designators 16 and 32 indicate the length (in bits) of the frame check sequence (FCS). A CRC of 32 bits provides more powerful error detection, but adds overhead. Both the sender and receiver must use the same setting.
CRC-16, the most widely used throughout the United States and Europe, is used extensively with wide-area networks (WANs). CRC-32 is specified by IEEE 802 and as an option by some point-to-point transmission standards. It is often used on SMDS networks and LANs.
Example
In the following example, the 32-bit CRC is enabled on serial interface 3/0:
interface serial 3/0crc 32delay
To set a delay value for an interface, use the delay interface configuration command. Use the no form of this command to restore the default delay value.
delay tens-of-microseconds
no delaySyntax Description
tens-of-microseconds
Integer that specifies the delay in tens of microseconds for an interface or network segment.
Default
Default delay values may be displayed with the EXEC command show interfaces.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Example
The following example sets a 30,000-microsecond delay on serial interface 3:
interface serial 3 delay 30000Related Commands
You can use the master indexes or search online to find documentation of related commands.
show interfaces
dce-terminal-timing enable
When running the line at high speeds and long distances, use the dce-terminal-timing enable interface configuration command to prevent phase shifting of the data with respect to the clock. If SCTE is not available from the DTE, use no form of this command, which causes the DCE to use its own clock instead of SCTE from the DTE.
dce-terminal-timing enable
no dce-terminal-timing enableSyntax Description
This command has no keywords or arguments.
Default
DCE uses its own clock.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
On the Cisco 4000 platform, you can specify the serial Network Interface Module timing signal configuration. When the board is operating as a DCE and the DTE provides terminal timing (SCTE or TT), the dce-terminal-timing enable command causes the DCE to use SCTE from the DTE.
Example
The following example prevents phase shifting of the data with respect to the clock:
interface serial 0 dce-terminal-timing enabledescription (controller)
Use the description controller configuration command to add a description to an E1 or T1 controller or the Channelized T3 Interface Processor (CT3IP) in Cisco 7500 series routers. Use the no form of this command to remove the description.
description string
no descriptionSyntax Description
string
Comment or a description to help you remember what is attached to the interface. Up to 80 characters.
Default
No description is added.
Command Mode
Controller configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
This command was modified in Cisco IOS Release 11.3 to include the CT3IP controller.
The description command is meant solely as a comment to be put in the configuration to help you remember what certain controllers are used for. The description affects the CT3IP and MIP interfaces only and appears in the output of the show controller t3, show controller e1, show controller t1, and show running-config EXEC commands.
Example
The following example describes a 3174 controller:
controller t1description 3174 Controller for test labRelated Commands
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show controller e1
show controller t1
show controller t3
show running-configdown-when-looped
Use the down-when-looped interface configuration command to configure an interface to inform the system it is down when loopback is detected.
down-when-looped
Syntax Description
This command has no arguments or keywords.
Default
Disabled
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command is valid for HDLC or PPP encapsulation on serial and HSSI interfaces.
Backup Interfaces
When an interface has a backup interface configured, it is often desirable that the backup interface be enabled when the primary interface is either down or in loopback. By default, the backup is only enabled if the primary interface is down. By using the down-when-looped command, the backup interface will also be enabled if the primary interface is in loopback.
Testing an Interface with the Loopback Command
If testing an interface with the loopback command, or by placing the DCE into loopback, down-when-looped should not be configured; otherwise, packets will not be transmitted out the interface that is being tested.
Example
In the following example, interface serial 0 is configured for HDLC encapsulation. It is then configured to let the system know that it is down when in loopback mode.
interface serial0encapsulation hdlcdown-when-loopedRelated Commands
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backup interface serial
loopback (interface)dte-invert-txc
Use the dte-invert-txc interface configuration command to invert the TXC clock signal received from the DCE. Use the no form of this command if the DCE accepts SCTE from the DTE.
dte-invert-txc
no dte-invert-txcSyntax Description
This command has no arguments or keywords.
Default
Disabled
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Use this command if the DCE cannot receive SCTE from the DTE, the data is running at high speeds, and the transmission line is long. This prevents phase shifting of the data with respect to the clock.
On the Cisco 4000 series, you can specify the serial Network Processor Module timing signal configuration. When the board is operating as a DTE, the dte-invert-txc command inverts the TXC clock signal it gets from the DCE that the DTE uses to transmit data. If the DCE accepts SCTE from the DTE, use no dte-invert-txc.
Example
The following example inverts the TXC on serial interface 0:
interface serial 0 dte-invert-txcearly-token-release
To enable early token release on Token Ring interfaces, use the early-token-release interface configuration command. Once enabled, use the no form of this command to disable this feature.
early-token-release
no early-token-releaseSyntax Description
This command has no arguments or keywords.
Default
Disabled
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Early token release is a method whereby the Token Ring interfaces can release the token back onto the ring immediately after transmitting, rather than waiting for the frame to return. This feature helps increase the total bandwidth of the Token Ring.
The Token Ring Interface Processor (TRIP) on the Cisco 7500 series routers and the Token Ring adapters on the Cisco 7200 series routers all support early token release.
Examples
The following example enables the use of early token release on Token Ring interface 1:
interface tokenring 1early-token-releaseOn the Cisco 7500 series, to enable the use of early token release on your Token Ring interface processor in slot 4 on port 1, issue the following configuration commands:
interface tokenring 4/1early-token-releaseencapsulation
To set the encapsulation method used by the interface, use the encapsulation interface configuration command.
encapsulation encapsulation-type
Syntax Description
Default
The default depends on the type of interface. For example, a synchronous serial interface defaults to HDLC.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
To use SLIP or PPP, the router or access server must be configured with an IP routing protocol or with the ip host-routing command. This configuration is done automatically if you are using old-style slip address commands. However, you must configure it manually if you configure SLIP or PPP via the interface async command.
Examples
The following example resets HDLC serial encapsulation on serial interface 1:
interface serial 1 encapsulation hdlcThe following example enables PPP encapsulation on serial interface 0:
interface serial 0encapsulation pppRelated Commands
You can use the master indexes or search online to find documentation of related commands.
keepalive
ppp
ppp authentication
slipfddi burst-count
Use the fddi burst-count interface configuration command to allow the FCI card to preallocate buffers to handle bursty FDDI traffic (for example, NFS bursty traffic). Use the no form of this command to revert to the default value.
fddi burst-count number
no fddi burst-countSyntax Description
Default
3 buffers
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command applies to the FCI card only. The microcode software version should not be 128.45 or 128.43.
Example
The following example sets the number of buffers to 5:
interface fddi 0 fddi burst-count 5fddi c-min
To set the C-Min timer on the PCM, use the fddi c-min interface configuration command. Use the no form of this command to revert to the default value.
fddi c-min microseconds
no fddi c-minSyntax Description
Default
1600 microseconds
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command applies to the processor CMT only. You need extensive knowledge of the PCM state machine to tune this timer. Use this command when you run into PCM interoperability problems.
Example
The following example sets the C-Min timer to 2000 microseconds:
interface fddi 0 fddi c-min 2000Related Commands
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fddi tb-min
fddi tl-min-time
fddi t-outfddi cmt-signal-bits
To control the information transmitted during the connection management (CMT) signaling phase, use the fddi cmt-signal-bits interface configuration command.
fddi cmt-signal-bits signal-bits [phy-a | phy-b]
Syntax Description
Defaults
The default signal bits for the phy-a and phy-b keywords are as follows:
•
•
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
If neither the phy-a nor phy-b keyword is specified, the signal bits apply to both physical connections.
Note
Table 28 FDDI Physical Type Bit Specifications
0
0
Physical A
1
0
Physical B
0
1
Physical S
1
1
Physical M
Example
The following example sets the CMT signaling phase to signal bits 0x208 on both physical connections:
interface fddi 0 fddi cmt-signal-bits 208fddi duplicate-address-check
Use the fddi duplicate-address-check interface configuration command to turn on the duplicate address detection capability on the FDDI. Use the no form of this command to disable this feature.
fddi duplicate-address-check
no fddi duplicate-address-checkSyntax Description
This command has no arguments or keywords.
Default
Disabled
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
If you use this command, the Cisco IOS software will detect a duplicate address if multiple stations are sharing the same MAC address. If the software finds a duplicate address, it will shut down the interface.
Example
The following example enables duplicate address checking on the FDDI:
interface fddi 0 fddi duplicate-address-checkfddi encapsulate
Use the fddi encapsulate interface configuration command to specify encapsulating bridge mode on the CSC-C2/FCIT interface card. Use the no form of this command to turn off encapsulation bridging and return the FCIT interface to its translational, nonencapsulating mode.
fddi encapsulate
no fddi encapsulateSyntax Description
This command has no arguments or keywords.
Default
The FDDI interface by default uses the SNAP encapsulation format defined in RFC 1042. It is not necessary to define an encapsulation method for this interface when using the CSC-FCI interface card.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
The no fddi encapsulate command applies only to CSC-C2/FCIT interfaces, because the CSC-FCI interfaces are always in encapsulating bridge mode. The CSC-C2/FCIT interface card fully supports transparent and translational bridging for the following configurations:
•
•
•
The command fddi encapsulate puts the CSC-C2/FCIT interface into encapsulation mode when doing bridging. In transparent mode, the FCIT interface interoperates with earlier versions of the CSC-FCI encapsulating interfaces when performing bridging functions on the same ring.
CautionBridging between dissimilar media presents several problems that can prevent communications from occurring. These problems include bit-order translation (or usage of MAC addresses as data), maximum transfer unit (MTU) differences, frame status differences, and multicast address usage. Some or all of these problems might be present in a multimedia bridged LAN and might prevent communication from taking place. These problems are most prevalent when bridging between Token Rings and Ethernets or between Token Rings and FDDI nets. This is because of the different way Token Ring is implemented by the end nodes.
The following protocols have problems when bridged between Token Ring and other media: Novell IPX, DECnet Phase IV, AppleTalk, VINES, XNS, and IP. Further, the following protocols may have problems when bridged between FDDI and other media: Novell IPX and XNS. We recommend that these protocols be routed whenever possible.
Example
The following example sets FDDI interface 1 on the CSC-C2/FCIT interface card to encapsulating bridge mode:
interface fddi 1 fddi encapsulatefddi smt-frames
Use the fddi smt-frames interface configuration command to enable the SMT frame processing capability on the FDDI. Use the no form of this command to disable this feature and prevent the Cisco IOS software from generating or responding to SMT frames.
fddi smt-frames
no fddi smt-framesSyntax Description
This command has no arguments or keywords.
Default
Enabled
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Use the no form of this command to turn off SMT frame processing for diagnosing purposes. Use the fddi smt-frames command to reenable the feature.
Example
The following example disables SMT frame processing:
interface fddi 0 no fddi smt-framesfddi tb-min
Use the fddi tb-min interface configuration command to set the TB-Min timer in the physical connection management (PCM). Use the no form of this command to revert to the default value.
fddi tb-min milliseconds
no fddi tb-minSyntax Description
Default
100 ms
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.3.
This command applies to the processor CMT only. You need extensive knowledge of the PCM state machine to tune this timer. Use this command when you run into PCM interoperability problems.
Example
The following example sets the TB-Min timer to 200 ms:
interface fddi 0 fddi tb-min 200Related Commands
You can use the master indexes or search online to find documentation of related commands.
fddi c-min
fddi tl-min-time
fddi t-outfddi tl-min-time
Use the fddi tl-min-time interface configuration command to control the TL-Min time (the minimum time to transmit a Physical Sublayer, or PHY line state, before advancing to the next physical connection management [PCM] state, as defined by the X3T9.5 specification).
fddi tl-min-time microseconds
Syntax Description
Default
30 microseconds
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Interoperability tests have shown that some implementations of the FDDI standard need more than 30 microseconds to sense a signal.
Examples
The following example changes the TL-Min time from 30 microseconds to 100 microseconds:
interface fddi 0fddi tl-min-time 100The following example changes the TL-Min time from 30 microseconds to 100 microseconds on a Cisco 7500 series router:
interface fddi 3/0fddi tl-min-time 100Related Commands
You can use the master indexes or search online to find documentation of related commands.
fddi c-min
fddi tl-min-time
fddi t-outfddi t-out
Use the fddi t-out interface configuration command to set the t-out timer in the physical connection management (PCM). Use the no form of this command to revert to the default value.
fddi t-out milliseconds
no fddi t-outSyntax Description
Default
100 ms
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command applies to the processor CMT only. You need extensive knowledge of the PCM state machine to tune this timer. Use this command when you run into PCM interoperability problems.
Example
The following example sets the timeout timer to 200 ms:
interface fddi 0fddi t-out 200Related Commands
You can use the master indexes or search online to find documentation of related commands.
fddi c-min
fddi tb-min
fddi tl-min-timefddi token-rotation-time
Use the fddi token-rotation-time interface configuration command to control ring scheduling during normal operation and to detect and recover from serious ring error situations.
fddi token-rotation-time microseconds
Syntax Description
microseconds
Number that specifies the token rotation time (TRT). The default is 5,000 microseconds.
Default
5000 microseconds
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
The FDDI standard restricts the allowed time to be greater than 4000 microseconds and less than 165,000 microseconds. As defined in the X3T9.5 specification, the value remaining in the TRT is loaded into the token holding timer (THT). Combining the values of these two timers provides the means to determine the amount of bandwidth available for subsequent transmissions.
Examples
The following example sets the rotation time to 24,000 microseconds:
interface fddi 0fddi token-rotation-time 24000The following example sets the rotation time to 24,000 microseconds on a Cisco 7500 series router:
interface fddi 3/0fddi token-rotation-time 24000fddi valid-transmission-time
To recover from a transient ring error, use the fddi valid-transmission-time interface configuration command.
fddi valid-transmission-time microseconds
Syntax Description
microseconds
Number that specifies the transmission valid timer (TVX) interval. The default is 2,500 microseconds.
Default
2,500 microseconds
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
Examples
The following example changes the transmission timer interval to 3000 microseconds:
interface fddi 0fddi valid-transmission-time 3000The following example changes the transmission timer interval to 3000 microseconds on a Cisco 7000 or Cisco 7200:
interface fddi 3/0fddi valid-transmission-time 3000fdl
To set the facilities data link exchange standard for the CSU on the AS5200's T1 controllers, enter the fdl controller configuration command. The no form of this command disables this facilities data-link support.
fdl {att | ansi}
no fdl {att | ansi}Syntax Description
att
Selects AT&T technical reference 54016 for extended superframe facilities data link exchange support.
ansi
Selects ANSI T1.403 for extended superframe facilities data link exchange support.
Default
Disabled
Command Mode
Controller configuration
Usage Guidelines
You must configure this command on both T1 controllers if you want to support the CSU function on each T1 line. However, you must use the same facilities data link exchange standard as your service provider. You can have a different standard configured on each T1 controller.
Example
The following example configures the ANSI T1.403 standard for both T1 controllers:
AS5200(config)# controller t1 0AS5200(config-controller)# fdl ansiAS5200(config-controller)# exitAS5200(config)# controller t1 1AS5200(config-controller)# fdl ansiframing
Use the framing controller configuration command to select the frame type for the T1 or E1 data line.
framing {sf | esf} (for T1 lines)
framing {crc4 | no-crc4} [australia] (for E1 lines)Syntax Description
Defaults
Super frame is the default on a T1 line.
CRC4 frame is the default on an E1 line.
Command Mode
Controller configuration
Usage Guidelines
Use this command in configurations where the router or access server is intended to communicate with T1 or E1 fractional data line. The service provider determines which framing type, either sf, esf, or crc4, is required for your T1/E1 circuit.
Example
The following example selects extended super frame as the T1 frame type:
framing esfRelated Commands
You can use the master indexes or search online to find documentation of related commands.
cablelength
linecode
