|
|
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
tens-of-microseconds | Integer that specifies the delay in tens of microseconds for an interface or network segment. |
Default delay values may be displayed with the EXEC command show interfaces.
Interface configuration
This command first appeared in Cisco IOS Release 10.0.
The following example sets a 30,000-microsecond delay on serial interface 3:
interface serial 3
delay 30000
You can use the master indexes or search online to find documentation of related commands.
show interfaces
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 enableThis command has no keywords or arguments.
DCE uses its own clock.
Interface configuration
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.
The following example prevents phase shifting of the data with respect to the clock:
interface serial 0
dce-terminal-timing enable
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
string | Comment or a description to help you remember what is attached to the interface. Up to 80 characters. |
No description is added.
Controller configuration
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 more system:running-config EXEC commands.
The following example describes a 3174 controller:
controller t1 description 3174 Controller for test lab
You can use the master indexes or search online to find documentation of related commands.
show controller e1
show controller t1
show controller t3
more system:running-config
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-loopedThis command has no arguments or keywords.
Disabled
Interface configuration
This command first appeared in Cisco IOS Release 10.0.
This command is valid for HDLC or PPP encapsulation on serial and HSSI 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.
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.
The following example configures interface serial 0 for HDLC encapsulation. It is then configured to let the system know that it is down when in loopback mode.
interface serial0 encapsulation hdlc down-when-looped
You can use the master indexes or search online to find documentation of related commands.
backup interface serial
loopback (interface)
To specify the maximum allowable bandwidth used by the PA-E3 port adapter and PA-T3 port adapter, use the dsu bandwidth interface configuration command. To return to the default bandwidth, use the no form of this command.
dsu bandwidth kbps
kbps | Maximum bandwidth in the range of 22 kbps to 44736 kbps. The default varies for different port adapters. |
34010 kbps for PA-E3
44736 kbps for PA-T3
Interface configuration
This command first appeared in Cisco IOS Release 11.1 CA.
The local interface configuration must match the remote interface configuration. For example, if you reduce the maximum bandwidth to 16000 on the local port, you must also do the same on the remote port.
The dsu bandwidth command reduces the bandwidth by padding the E3 and T3 frame.
To verify the data service unit (DSU) bandwidth configured on the interface, use the show controller serial EXEC command.
The following example sets the DSU bandwidth to 16000 kbps on interface 1/0/0:
interface serial 1/0/0 dsu bandwidth 16000
You can use the master indexes or search online to find documentation of related commands.
To specify the interoperability mode used by a PA-E3 port adapter or PA-T3 port adapter, use the dsu mode interface configuration command. To return to the default mode, use the no form of this command.
dsu mode {0 | 1 | 2}
0 | Sets the interoperability mode to 0. This is the default. Specify mode 0 to connect a PA-E3 port adapter to another PA-E3 port adapter or to a Digital Link DSU (DL3100). Use mode 0 to connect a PA-T3 port adapter to another PA-T3 port adapter or to a Digital Link DSU (DL3100). |
1 | Sets the interoperability mode to 1. Specify mode 1 to connect a PA-E3 port adapter or PA-T3 port adapter to a Kentrox DSU. |
2 | Sets the interoperability mode to 2. Specify mode 2 to connect a PA-T3 port adapter to a Larscom DSU. |
0 mode
Interface configuration
This command first appeared in Cisco IOS Release 11.1 CA.
The local interface configuration must match the remote interface configuration. For example, if you define the data service unit (DSU) interoperability mode as 1 on the local port, you must also do the same on the remote port.
You must know what type of DSU is connected to the remote port to determine if it interoperates with a PA-E3 port adapter or a PA-T3 port adapter. Use mode 0 to connect a PA-E3 port adapter to another PA-E3 port adapter or to a Digital Link DSU (DL3100). Use mode 0 to connect a PA-T3 port adapter to another PA-T3 port adapter or to a Digital Link DSU (DL3100). Use mode 1 to connect a PA-E3 port adapter or a PA-T3 port adapter to a Kentrox DSU. Use mode 2 to connect a PA-T3 port adapter to a Larscom DSU. The dsu mode command enables and improves interoperability with other DSUs.
The dsu mode command enables and improves interoperability with other DSUs.
To verify the DSU mode configured on the interface, use the show controller serial EXEC command.
The following example sets the DSU mode to 1 on interface 1/0/0:
interface serial 1/0/0 dsu mode 1
You can use the master indexes or search online to find documentation of related commands.
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-txcThis command has no arguments or keywords.
Disabled
Interface configuration
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.
The following example inverts the TXC on serial interface 0:
interface serial 0
dte-invert-txc
To configure the duplex operation on an interface, use the duplex interface configuration command. Use the no form of this command to return the system to half-duplex mode, which is the system default.
duplex {full | half | auto}
full | Specifies full-duplex operation. |
half | Specifies half-duplex operation. |
auto | Specifies the auto negotiation capability. The interface automatically operates at half or full duplex, depending on environmental factors, such as the type of media and transmission speeds for the peer routers, hubs, and switches used in the network configuration. |
Half-duplex mode
Interface configuration
This command first appeared in Cisco IOS Release 11.2(10)P.
To use the auto-negotiation capability (that is, detect speed and duplex modes automatically), you must set both speed and duplex to auto. Setting speed to auto negotiates speed only, and setting duplex to auto negotiates duplex only.
Table 7 describes the access server's performance for different combinations of the duplex and speed modes. The specified duplex command configured with the specified speed command produces the resulting system action.
| Duplex Commands | Speed Commands | Resulting System Action |
|---|---|---|
duplex auto | speed auto | Auto negotiates both speed and duplex modes. |
duplex auto | speed 100 or speed 10 | Auto negotiates both speed and duplex modes. |
duplex half or duplex full | speed auto | Auto negotiates both speed and duplex modes. |
duplex half | speed 10 | Forces 10 Mbps and half duplex. |
duplex full | speed 10 | Forces 10 Mbps and full duplex. |
duplex half | speed 100 | Forces 100 Mbps and half duplex. |
duplex full | speed 100 | Forces 100 Mbps and full duplex. |
For the Cisco AS5300, the duplex {full | half | auto} command syntax replaces the following two earlier duplex commands:
You will get the following error messages if you try to use these commands on a Cisco AS5300:
router(config)# interface fastethernet 0
router(config-if)# full-duplex
Please use duplex command to configure duplex mode router(config-if)# router(config-if)# half-duplex
Please use duplex command to configure duplex mode
The following example shows the different duplex configuration options you can configure on a Cisco AS5300:
router# configure terminal
Enter configuration commands, one per line. End with CNTL/Z. router(config)# interface fastethernet 0
router(config-if)# duplex ?
auto Enable AUTO duplex configuration full Force full duplex operation half Force half-duplex operation
You can use the master indexes or search online to find documentation of related commands.
duplex
interface fastethernet
show controller fastethernet
speed
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-releaseThis command has no arguments or keywords.
Disabled
Interface configuration
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.
The following example enables the use of early token release on Token Ring interface 1:
interface tokenring 1 early-token-release
On 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 4/1 early-token-release
To set the encapsulation method used by the interface, use the encapsulation interface configuration command.
encapsulation encapsulation-type
encapsulation-type | Encapsulation type; one of the following keywords: · atm-dxi---Asynchronous Transfer Mode-Data Exchange Interface. · bstun---Block Serial Tunnel. · frame-relay---Frame Relay (for serial interface). · hdlc---High-Level Data Link Control (HDLC) protocol for serial interface. This encapsulation method provides the synchronous framing and error detection functions of HDLC without windowing or retransmission. · isl --- Inter-Switch Link (ISL) (for virtual LANs) · lapb---X.25 LAPB DTE operation (for serial interface). · ppp---Point-to-Point Protocol (PPP) (for serial interface). · sde---IEEE 802.10 Security Data Exchange. · sdlc---IBM serial SNA. · sdlc-primary---IBM serial SNA (for primary serial interface). · sdlc-secondary---IBM serial SNA (for secondary serial interface). · smds---Switched Multimegabit Data Services (SMDS) (for serial interface). |
The default depends on the type of interface. For example, a synchronous serial interface defaults to HDLC.
Interface configuration
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.
The following example resets HDLC serial encapsulation on serial interface 1:
interface serial 1
encapsulation hdlc
The following example enables PPP encapsulation on serial interface 0:
interface serial 0 encapsulation ppp
You can use the master indexes or search online to find documentation of related commands.
keepalive
ppp
ppp authentication
slip
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 numbernumber | Number of preallocated buffers in the range from 1 to 10. The default is 3 buffers. |
3 buffers
Interface configuration
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.
The following example sets the number of buffers to 5:
interface fddi 0
fddi burst-count 5
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 microsecondsmicroseconds | Sets the timer value in microseconds. The default is 1600 microseconds. |
1600 microseconds
Interface configuration
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.
The following example sets the C-Min timer to 2000 microseconds:
interface fddi 0
fddi c-min 2000
You can use the master indexes or search online to find documentation of related commands.
fddi tb-min
fddi tl-min-time
fddi t-out
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]
signal-bits | A hexadecimal number preceded by 0x; for example, 0x208. The FDDI standard defines ten bits of signaling information that must be transmitted, as follows: · bit 0---Escape bit. Reserved for future assignment by the FDDI standards committee. · bits 1 and 2---Physical type, as defined in Table 8. · bit 3---Physical compatibility. Set if topology rules include the connection of a physical-to-physical type at the end of the connection. · bits 4 and 5---Link confidence test duration; set as defined in Table 9. · bit 6---Media Access Control (MAC) available for link confidence test. · bit 7---Link confidence test failed. The setting of bit 7 indicates that the link confidence was failed by the Cisco end of the connection. · bit 8---MAC for local loop. · bit 9---MAC on physical output. |
phy-a | (Optional) Selects Physical Sublayer A. |
phy-b | (Optional) Selects Physical Sublayer B. |
The default signal bits for the phy-a and phy-b keywords are as follows:
Interface configuration
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.
Table 8 lists the physical types.
| Bit 2 | Bit 1 | Physical Type |
|---|---|---|
0 | 0 | Physical A |
1 | 0 | Physical B |
0 | 1 | Physical S |
1 | 1 | Physical M |
Table 9 lists the duration bits.
| Bit 5 | Bit 4 | Test Duration |
|---|---|---|
0 | 0 | Short test (default 50 ms) |
1 | 0 | Medium test (default 500 ms) |
0 | 1 | Long test (default 5 seconds) |
1 | 1 | Extended test (default 50 seconds) |
The following example sets the CMT signaling phase to signal bits 0x208 on both physical connections:
interface fddi 0
fddi cmt-signal-bits 208
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-checkThis command has no arguments or keywords.
Disabled
Interface configuration
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.
The following example enables duplicate address checking on the FDDI:
interface fddi 0
fddi duplicate-address-check
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 encapsulateThis command has no arguments or keywords.
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.
Interface configuration
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.
 | Caution Bridging 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.
The following example sets FDDI interface 1 on the CSC-C2/FCIT interface card to encapsulating bridge mode:
interface fddi 1
fddi encapsulate
To specify the maximum number of frames that the FDDI interface will transmit per token capture, use the fddi frames-per-token interface configuration command. Us the no form of this command to revert to the default value.
fddi frames-per-token number
number | Maximum number of frames to transmit per token capture. Valid values are from 1 to 10. the default is 3. |
3 frames
Interface configuration
This command first appeared in Cisco IOS Release 11.2 P.
Changing the value will increase or decrease the maximum number of frames that the FDDI interface can transmit when it receives a token. Increasing the value does not necessarily mean more frames will be transmitted on each token capture. This is heavily dependent on the traffic load of the specific interface.
When the interface captures a token, it transmits all of the frames that are queued in the interface's transmit ring, up to a maximum value specified by the fddi frames-per-token command.
If there are no frames ready for transmission, the token is passed on, and no frames are transmitted. If there are less than the fddi frames-per-token value in the transmit ring, all frames in the transmit ring are transmitted before the token is passed on. If there are more than the fddi frames-per-token value in the transmit ring, the specified value is transmitted before the token is passed on. The remaining frames in the transmit ring remain queued until the token is captured again.
The following example shows how to configure the FDDI interface to transmit four frames per token capture:
! Show fddi frames-per-token command options
4700(config-if)#fddi frames-per-token ?
<1-10> Number of frames per token, default = 3
! Specify 4 as the maximum number of frames to be transmitted per token
4700(config-if)#fddi frames-per-token 4
To enable the SMT frame processing capability on the FDDI, use the fddi smt-frames interface configuration command. Use the no form of this command to disable this function and prevent the Cisco IOS software from generating or responding to SMT frames.
fddi smt-framesThis command has no arguments or keywords.
Enabled
Interface configuration
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.
The following example disables SMT frame processing:
interface fddi 0
no fddi smt-frames
To set the TB-Min timer in the physical connection management (PCM), use the fddi tb-min interface configuration command. Use the no form of this command to revert to the default value.
fddi tb-min millisecondsmilliseconds | Number that sets the TB-Min timer value. The default is 100 milliseconds. |
100 milliseconds
Interface configuration
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.
The following example sets the TB-Min timer to 200 milliseconds:
interface fddi 0
fddi tb-min 200
You can use the master indexes or search online to find documentation of related commands.
fddi c-min
fddi tl-min-time
fddi t-out
microseconds | Number that specifies the time used during the connection management (CMT) phase to ensure that signals are maintained for at least the value of TL-Min so the remote station can acquire the signal. The default is 30 microseconds. |
30 microseconds
Interface configuration
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.
The following example changes the TL-Min time from 30 microseconds to 100 microseconds:
interface fddi 0 fddi tl-min-time 100
The following example changes the TL-Min time from 30 microseconds to 100 microseconds on a Cisco 7500 series router:
interface fddi 3/0 fddi tl-min-time 100
You can use the master indexes or search online to find documentation of related commands.
fddi c-min
fddi tl-min-time
fddi t-out
To set the t-out timer in the physical connection management (PCM), use the fddi t-out interface configuration command. Use the no form of this command to revert to the default value.
fddi t-out millisecondsmilliseconds | Number that sets the timeout timer. The default is 100 milliseconds. |
100 milliseconds
Interface configuration
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.
The following example sets the timeout timer to 200 milliseconds:
interface fddi 0 fddi t-out 200
You can use the master indexes or search online to find documentation of related commands.
fddi c-min
fddi tb-min
fddi tl-min-time
To control ring scheduling during normal operation and to detect and recover from serious ring error situations, use the fddi token-rotation-time interface configuration command.
fddi token-rotation-time microseconds
microseconds | Number that specifies the token rotation time (TRT). The default is 5,000 microseconds. |
5000 microseconds
Interface configuration
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.
The following example sets the rotation time to 24,000 microseconds:
interface fddi 0 fddi token-rotation-time 24000
The following example sets the rotation time to 24,000 microseconds on a Cisco 7500 series router:
interface fddi 3/0 fddi token-rotation-time 24000
To recover from a transient ring error, use the fddi valid-transmission-time interface configuration command.
fddi valid-transmission-time microseconds
microseconds | Number that specifies the transmission valid timer (TVX) interval. The default is 2,500 microseconds. |
2,500 microseconds
Interface configuration
This command first appeared in Cisco IOS Release 10.0.
The following example changes the transmission timer interval to 3000 microseconds:
interface fddi 0 fddi valid-transmission-time 3000
The following example changes the transmission timer interval to 3000 microseconds on a Cisco 7000 series routers or Cisco 7200 series routers:
interface fddi 3/0 fddi valid-transmission-time 3000
To set the facilities data link exchange standard for the CSU controllers, enter the fdl controller configuration command. Use the no form of this command, to disables facilities data-link support.
fdl {att | ansi | both}
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. |
both | (Supported on the Cisco MC3810 only) Specifies to support both AT&T technical reference 54016 and ANSI T1.403 for extended superframe facilities data link excchange support. |
Disabled
Controller configuration
This command first appeared in Cisco IOS Release 11.3.
This command was modified in Cisco IOS Release 12.0, to add command syntax both for the MC3810.
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.
The following example configures the ANSI T1.403 standard for both T1 controllers:
Router(config)# controller t1 0
Router(config-controller)# fdl ansi
Router(config-controller)# exit
Router(config)# controller t1 1
Router(config-controller)# fdl ansi
Use the framing controller configuration command to select the frame type for the E1 or T1 data line.
framing {sf | esf} (for T1 lines)
sf | Specifies super frame as the T1 frame type. |
esf | Specifies extended super frame as the T1 frame type. |
crc4 | Specifies CRC4 frame as the E1 frame type. |
no-crc4 | Specifies no CRC4 frame as the E1 frame type. |
australia | (Optional) Specifies the E1 frame type used in Australia. |
Super frame is the default on a T1 line.
CRC4 frame is the default on an E1 line.
Controller configuration
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.
The following example selects extended super frame as the T1 frame type:
framing esf
You can use the master indexes or search online to find documentation of related commands.
cablelength
linecode
To specify E3 or T3 line framing for a PA-E3 port adapter or PA-T3 port adapter, use the framing interface configuration command. To return to the default G.751 framing or C-bit framing, use the no form of this command.
framing {bypass | g751} (PA-E3)
bypass | Specifies bypass E3 framing. |
g751 | Specifies G.751 E3 framing. This is the default for the PA-E3. |
c-bit | Specifies that the C-bit framing is used as the T3 framing type. This is the default for the PA-T3. |
m13 | Specifies m13 T3 framing. |
G.751 framing for PA-E3
C-bit framing for PA-T3
Interface configuration
This command first appeared in Cisco IOS Release 11.1 CA.
The default framing is described in the ITU-T Recommendation G.751.
When the framing mode is bypass, the E3 frame data is not included in the E3 frame, just the data.
When the framing mode is bypass, the T3 frame data is not included in the T3 frame, just the data.
If you use the bypass option, scrambling must be set to the default (disabled), the dsu mode must be set to the default (0), and the dsu bandwidth must be set to the default (44736).
To verify the framing mode configured on the interface, use the show controller serial EXEC command.
The following example sets the framing mode to bypass on interface 1/0/0:
interface serial 1/0/0 framing bypass
You can use the master indexes or search online to find documentation of related commands.
To specify T3 line framing used by the CT3IP port adapter, use the framing controller configuration command. Use the no form of this command to restore the default framing type.
framing {c-bit | m23 | auto-detect}
c-bit | Specifies that the C-bit framing is used as the T3 framing type. |
m23 | Specifies that the M23 framing is used as the T3 framing type. |
auto-detect | Specifies that the CT3IP detects the framing type it receives from the far-end equipment. This is the default. |
auto-detect for CT3IP
Controller configuration
This command first appeared in Cisco IOS Release 11.1 CA.
Because the CT3IP supports the Application Identification Channel (AIC) signal, the setting for the framing might be overridden by the CT3IP firmware.
You can also set the framing for each T1 channel by using the t1 framing controller configuration command.
The following example sets the framing for the CT3IP to C-bit:
controller t3 9/0/0 framing c-bit
You can use the master indexes or search online to find documentation of related commands.
To specify full-duplex mode on full-duplex single-mode and multimode port adapters, use the full-duplex interface configuration command. Use the no form of this command to restore the default half-duplex mode.
full-duplexThis command has no arguments or keywords.
Half-duplex mode is the default mode on a Cisco 7500 series router and a FEIP.
Half-duplex mode is the default mode for serial interfaces that are configured for bisynchronous tunneling.
Interface configuration
This command first appeared in Cisco IOS Release 11.1.
This command was modified in Cisco IOS Release 11.3 to include information on FDDI full-duplex, single-mode and multimode port adapters.
Use this command if the equipment on the other end is capable of full-duplex mode.
This command specifies full-duplex mode on full-duplex single-mode and multimode port adapters available on the following routers:
Refer to the Cisco Product Catalog for hardware compatibility information and for specific model numbers of port adapters.
To enable half-duplex mode, use the no full-duplex or half-duplex commands.
| Caution For the Cisco AS5300, the duplex {full | half | auto} command syntax replaces the full-duplex and half-duplex commands.You will get the following error messages if you try to use the full-duplex and half-duplex command on a Cisco AS5300: |
router(config)# interface fastethernet 0
router(config-if)# full-duplex
Please use duplex command to configure duplex mode router(config-if)# router(config-if)# half-duplex
Please use duplex command to configure duplex mode
Use the question mark command (?) to find out which port adapters support this command. If the interface does not support full-duplex, an informational message similar to the one shown below is displayed, and no changes are made to the interface. To determine if the interface supports full-duplex, use the show interfaces command. For example, the following message is displayed if the interface does not support full-duplex:
% interface does not support full-duplex.
Full-duplex autoconfiguration protocol allows an FDDI station to dynamically and automatically operate in either half-duplex (or ring) or full-duplex mode, and ensures that the stations fall back to ring mode when a configuration change occurs, such as a third station joining the ring.
After booting up, the FDDI stations begin operation in half-duplex mode. While the station performs the full-duplex autoconfiguration protocol, the station continues to provide data-link services to its users. Under normal conditions, the transition between half-duplex mode and full-duplex mode is transparent to the data-link users. The data-link services provided by full-duplex mode are functionally the same as the services provided by half-duplex mode.
If you change the full-duplex configuration (for example from disabled to enabled) on supported interfaces, the interface resets.
The following example configures full duplex mode on the Cisco 7000 series routers:
interface fastethernet 0/1
full-duplex
The following example specifies full-duplex binary synchronous communications (BSC) mode:
interface serial 0 encapsulation bstun full-duplex
The following example enables full-duplex mode on FDDI interface 0:
interface fddi 0/1/0 full-duplex
You can use the master indexes or search online to find documentation of related commands.
half-duplex
interface fastethernet
interface fddi
interface serial
Use the half-duplex interface configuration command to specify half-duplex mode on an SDLC interface or on the FDDI full-duplex, single-mode port adapter and FDDI full-duplex, multimode port adapter on the Cisco 7200 series, and Cisco 7500 series routers. Refer to the Cisco Product Catalog for specific model numbers of port adapters.
Use the no form of this command to reset the interface for full-duplex mode.
half-duplexThis command has no arguments or keywords.
Disabled
Interface configuration
This command first appeared in Cisco IOS Release 11.1.
This command was modified in Cisco IOS Release 11.3 to include information on FDDI full-duplex, single-mode and multimode port adapters.
The half-duplex command is used to configure an SDLC interface for half-duplex mode and is used on a variety of port adapters. Use the question mark command (?) to find out which port adapters support this command.
| Caution For the Cisco AS5300, the duplex {full | half | auto} command syntax replaces the full-duplex and half-duplex commands.You will get the following error messages if you try to use the full-duplex and half-duplex command on a Cisco AS5300: |
router(config)# interface fastethernet 0
router(config-if)# full-duplex
Please use duplex command to configure duplex mode router(config-if)# router(config-if)# half-duplex
Please use duplex command to configure duplex mode
To enable full-duplex mode, use the no half-duplex or full-duplex commands.
The following example configures an SDLC interface for half-duplex mode:
encapsulation sdlc-primary half-duplex
You can use the master indexes or search online to find documentation of related commands.
Use the half-duplex controlled-carrier interface configuration command to place a low-speed serial interface in controlled-carrier mode, instead of constant-carrier mode. Use the no form of this command to return the interface to constant-carrier mode.
half-duplex controlled-carrierThis command has no arguments or keywords.
Constant-carrier mode, where DCD is held constant and asserted by the DCE half-duplex interface.
Interface configuration
This command first appeared in Cisco IOS Release 11.2.
This command applies only to low-speed serial DCE interfaces in half-duplex mode. Configure a serial interface for half-duplex mode by using the media-type half-duplex command. These interfaces are available on Cisco 2520 through 2523 routers.
Controlled-carrier operation means that the DCE interface has DCD deasserted in the quiescent state. When the interface has something to transmit, it asserts DCD, waits a user-configured amount of time, then starts the transmission. When the interface has finished transmitting, it waits a user-configured amount of time and then deasserts DCD.
The following examples place the interface in controlled-carrier mode and back into constant-carrier operation.
Changing to controlled-carrier mode from the default of constant-carrier operation:
interface serial 2 half-duplex controlled-carrier
Changing to constant-carrier operation from controlled-carrier mode:
interface serial 2 no half-duplex controlled-carrier
You can use the master indexes or search online to find documentation of related commands.
half-duplex timer
physical-layer
To tune half-duplex timers, use the half-duplex timer interface configuration command. Use the no form of this command, along with the appropriate keyword, to return to the default value for that parameter.
half-duplex timer {cts-delay value | cts-drop-timeout value | dcd-drop-delay value |You can configure more than one of these options, but each option must be specified as a separate command.
cts-delay value | Specifies the delay introduced by the DCE interface between the time it detects RTS to the time it asserts CTS in response. The range is dependent on the serial interface hardware. The default value is 0 milliseconds. |
cts-drop-timeout value | Determines the amount of time a DTE interface waits for CTS to be deasserted after it has deasserted RTS. If CTS is not deasserted during this time, an error counter is incremented to note this event. The range is 0 to 1140000 milliseconds (1140 seconds). The default value is 250 milliseconds. |
dcd-drop-delay value | Applies to DCE half-duplex interfaces operating in controlled-carrier mode (see the half-duplex controlled-carrier command). This timer determines the delay between the end of transmission by the DCE and the deassertion of DCD. The range is 0 to 4400 milliseconds (4.4 seconds). The default value is 100 milliseconds. |
dcd-txstart-delay value | Applies to DCE half-duplex interfaces operating in controlled-carrier mode. This timer determines the time delay between the assertion of DCD and the start of data transmission by the DCE interface. The range is 0 to 1140000 ms (1140 seconds). The default value is 100 milliseconds. |
rts-drop-delay value | Specifies the time delay between the end of transmission by the DTE interface and deassertion of RTS. The range is 0 to 1140000 milliseconds (1140 seconds). The default value is 3 milliseconds. |
rts-timeout value | Determines the number of milliseconds the DTE waits for CTS to be asserted after the assertion of RTS before giving up on its transmission attempt. If CTS is not asserted in the specified amount of time, an error counter is incremented. The range is dependent on the serial interface hardware. The default value is 3 milliseconds. |
transmit-delay value | Specifies the number of milliseconds a half-duplex interface will delay the start of transmission. In the case of a DTE interface, this delay specifies how long the interface waits after something shows up in the transmit queue before asserting RTS. For a DCE interface, this dictates how long the interface waits after data is placed in the transmit queue before starting transmission. If the DCE interface is in controlled-carrier mode, this delay shows up as a delayed assertion of DCD. This timer enables the transmitter to be adjusted if the receiver is a little slow and is not able to keep up with the transmitter. The range is 0 to 4400 milliseconds (4.4 seconds). The default value is 0 milliseconds. |
The default cts-delay value is 0 milliseconds.
The default cts-drop-timeout value is 250 milliseconds.
The default dcd-drop-delay value is 100 milliseconds.
The default dcd-txstart-delay value is 100 milliseconds.
The default rts-drop-delay value is 3 milliseconds.
The default rts-timeout value is 3 milliseconds.
The default transmit-delay value is 0 milliseconds.
Interface configuration
This command first appeared in Cisco IOS Release 11.3.
The half-duplex timer command is used to tune half-duplex timers. With these timer tuning commands you can adjust the timing of the half-duplex state machines to suit the particular needs of their half-duplex installation.
The range of values for the cts-delay and rts-timeout keywords are dependent on the serial interface hardware.
The following example set the cts-delay timer to 10 ms and the transmit-delay timer to 50 milliseconds:
interface serial 2 half-duplex timer cts-delay 10 half-duplex timer transmit-delay 50
You can use the master indexes or search online to find documentation of related commands.
half-duplex controlled-carrier
physical-layer
To specify the hold-queue limit of an interface, use the hold-queue interface configuration command. Use the no form of this command with the appropriate keyword to restore the default values for an interface.
hold-queue length {in | out}
length | Integer that specifies the maximum number of packets in the queue. |
in | Specifies the input queue. |
out | Specifies the output queue. |
The default input hold-queue limit is 75 packets. The default output hold-queue limit is 40 packets. These limits prevent a malfunctioning interface from consuming an excessive amount of memory. There is no fixed upper limit to a queue size.
Interface configuration
This command first appeared in Cisco IOS Release 10.0.
The input hold queue prevents a single interface from flooding the network server with too many input packets. Further input packets are discarded if the interface has too many input packets outstanding in the system.
If priority output queueing is being used, the length of the four output queues is set using the priority-list global configuration command. The hold-queue command cannot be used to set an output hold queue length in this situation.
For slow links, use a small output hold-queue limit. This approach prevents storing packets at a rate that exceeds the transmission capability of the link. For fast links, use a large output hold-queue limit. A fast link may be busy for a short time (and thus require the hold queue), but can empty the output hold queue quickly when capacity returns.
To display the current hold queue setting and the number of packets discarded because of hold queue overflows, use the EXEC command show interfaces.
The following example sets a small input queue on a slow serial line:
interface serial 0
hold-queue 30 in
You can use the master indexes or search online to find documentation of related commands.
show interfaces
Use the hssi external-loop-request interface configuration command to allow the router to support a CSU/DSU that uses the LC signal to request a loopback from the router. Use the no form of this command to disable the feature.
hssi external-loop-requestThis command has no arguments or keywords.
Disabled
Interface configuration
This command first appeared in Cisco IOS Release 10.0.
The HSA applique (on the HSSI) contains an LED that indicates the LA, LB, and LC signals transiting through the devices. The CSU/DSU uses the LC signal to request a loopback from the router. The CSU/DSU may want to do this so that its own network management diagnostics can independently check the integrity of the connection between the CSU/DSU and the router.
Use this command to enable a two-way, internal, and external loopback request on HSSI from the CSU/DSU.
The following example enables a CSU/DSU to use the LC signal to request a loopback from the router:
hssi external-loop-request
To convert the HSSI interface into a clock master, use the hssi internal-clock interface configuration command. Use the no form of this command to disable the clock master mode.
hssi internal-clockThis command has no arguments or keywords.
Disabled
Interface configuration
This command first appeared in Cisco IOS Release 10.0.
Use this command in conjunction with the HSSI null-modem cable to connect two Cisco routers together with HSSI. You must configure this command at both ends of the link, not just one.
The following example converts the HSSI interface into a 45 MHz clock master:
hssi internal-clock 45 MHz
ethernet | Indicates that the hub is in front of an Ethernet interface. |
number | Hub number, starting with 0. Since there is currently only one hub, this number is 0. |
port | Port number on the hub. On the Cisco 2505, port numbers range from 1 to 8. On the Cisco 2507, port numbers range from 1 to 16. If a second port number follows, then the first port number indicates the beginning of a port range. |
end-port | (Optional) Last port number of a range. |
No hub ports are configured.
Global configuration
This command first appeared in Cisco IOS Release 10.3.
The following example enables port 1 on hub 0:
hub ethernet 0 1 no shutdown
The following example enables ports 1 through 8 on hub 0:
hub ethernet 0 1 8 no shutdown
You can use the master indexes or search online to find documentation of related commands.
shutdown
Use the ignore-dcd interface configuration command to configure the serial interface to monitor the DSR signal (instead of the DCD signal) as the line up/down indicator. Use the no form of this command to restore the default.
ignore-dcdThis command has no arguments or keywords.
The serial interface, operating in DTE mode, monitors the DCD signal as the line up/down indicator.
Interface configuration
This command first appeared in Cisco IOS Release 11.0.
This command applies to Quad Serial NIM interfaces on the Cisco 4000 series routers and Hitachi-based serial interfaces on the Cisco 2500 and 3000 series routers.
When the serial interface is operating in DTE mode, it monitors the Data Carrier Detect (DCD) signal as the line up/down indicator. By default, the attached DCE device sends the DCD signal. When the DTE interface detects the DCD signal, it changes the state of the interface to up.
In some configurations, such as an SDLC multidrop environment, the DCE device sends the Data Set Ready (DSR) signal instead of the DCD signal, which prevents the interface from coming up. Use this command to tell the interface to monitor the DSR signal instead of the DCD signal as the line up/down indicator.
The following example configures serial interface 0 to monitor the DSR signal as the line up/down indicator:
interface serial 0 ignore-dcd
To disable the monitoring of the LL pin when in DCE mode, enable the ingnore-hw local-loopback interface configuration command. To return to the default, use the no form of this command.
ignore-hw local-loopbackThis command has no arguments or keywords.
Enable
Interface configuration
This command first appeared in Cisco IOS Release 11.3.
Use this command if your system is experiencing spurious modem interrupts, which momentarily causes the interface to enter loopback mode. The end result of this behavior is flapping and the loss of SDLLC sessions.
The following example displays how to disable the monitoring of the LL pin when in DCE mode:
Router#conf term
Router(config)#interface serial 2
|
|