Cisco IOS Software Releases 11.1

Table Of Contents

PA-T3 and PA-2T3 Serial
Port Adapters

Description

Platforms

Configuration Tasks

Configure the PA-T3 Port Adapter

Troubleshoot the PA-T3 Port Adapter

Monitor and Maintain the PA-T3 Port Adapter

Configuration Example

Command Reference

cablelength

clock source

dsu bandwidth

dsu mode

framing

invert data

loopback

scramble

show controllers cbus

show controllers serial

show diag

show interfaces serial

Supported MIB

What to Do Next

PA-T3 and PA-2T3 Serial
Port Adapters

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Description

The PA-T3 and PA-2T3 serial port adapters are available on Cisco 7200 series routers, on second-generation Versatile Interface Processor (VIP2) in all Cisco 7500 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI). These port adapters provide one (PA-T3) or two (PA-2T3) high-speed full-duplex synchronous serial T3 interfaces and integrated data service unit (DSU) functionality.

The T3 port adapters can transmit and receive data at T3 rates of up to 45 Mbps and use a 75-ohm coaxial cable available from Cisco to connect to a serial T3 network. These port adapters support the following features:

•16- and 32-bit cyclic redundancy checks (CRC)

•High-speed HDLC data

•C-bit, M13, and bypass framing

•HDB3 line coding

•ATM-DXI, Frame Relay, HDLC, PPP, and SMDS serial encapsulation

•DS3 MIB (RFC 1407)

•Scrambling and reduced bandwidth

•Remote and local loopbacks

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Note   For additional information on interoperability guidelines for T3 serial port adapter DSUs, refer to the PA-T3 Serial Port Adapter Installation and Configuration publication.

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Platforms

This feature is supported on these platforms:

•Cisco 7200 series

•Cisco 7500 series

•Cisco 7000 series routers with the RSP7000 and RSP7000CI

Configuration Tasks

Perform the tasks in the following sections to configure the PA-T3 (all tasks are optional except for the first task):

•Configure the PA-T3 Port Adapter

•Troubleshoot the PA-T3 Port Adapter

•Monitor and Maintain the PA-T3 Port Adapter

For PA-T3 port adapter configuration examples, see the "Configuration Example" section, later in this chapter.

The PA-T3 supports most interface commands. For information about these commands, refer to the "Configuring Interfaces" chapter of the Configuration Fundamentals Configuration Guide. For additional information on how to configure the PA-T3 serial port adapter, refer to the "Configure a Synchronous Serial Interface" section in the "Configuring Interfaces" chapter of the Configuration Fundamentals Configuration Guide.

For information on other commands that can be used by the PA-T3 serial port adapter, refer to the Cisco IOS Release 11.1 configuration guides.

Configure the PA-T3 Port Adapter

In addition to the commands in the "Configure a Synchronous Serial Interface" section in the "Configuring Interfaces" chapter of the Configuration Fundamentals Configuration Guide, the commands listed in have been added to support the PA-T3 interface configuration. If you do not modify the configuration of the PA-T3, the configuration defaults shown in are used.

Table 1 PA-T3 Port Adapter Defaults

Command	Default Value
cablelength	50
clock source	line
crc 32	16-bit
dsu bandwidth	44736 kbps
dsu mode	0
framing	C-bit
invert data	data is not inverted
scramble	disabled

If you need to change any of the default configuration attributes, complete the first task in global configuration mode followed by any of the optional tasks in interface configuration mode:

Task	Command
Select the PA-T3 interface and enter interface configuration mode.	interface serial slot/port-adapter/port (Cisco 7500 series and Cisco 7000 series routers with the RSP7000 and RSP7000CI) interface serial slot/port (Cisco 7200 series)
Change the cable length.	cablelength length
Enable 32-bit CRC.	crc 32
Change the DSU bandwidth.	dsu bandwidth kbps
Change the DSU mode. To connect to another PA-T3 port adapter or a Digital Link DSU, use the default mode (0). To connect to a Kentrox DSU, use mode 1. To connect to a Larscom DSU, use mode 2.	dsu mode {0 | 1 | 2}
Change the framing used by the interface.	framing {c-bit | m13 | bypass}
Invert the data stream on the interface.	invert data
Enable scrambling on the interface.	scramble

Troubleshoot the PA-T3 Port Adapter

To set the following loopbacks to troubleshoot the PA-T3 port adapter using Cisco IOS software, perform the first task beginning in global configuration mode followed by any of the other tasks depending on your needs:

Task	Command
Loopback after the LIU toward the terminal.	loopback dte
Loopback after going through the framer toward the terminal.	loopback local
Loopback toward the network before going through the framer.	loopback network line
Loopback toward the network after going through the framer.	loopback network payload
Send a FEAC to set the remote framer in loopback.	loopback remote

These loopback commands loop all packets from the T3 interface either back to the interface or direct packets from the network back out toward the network.

Monitor and Maintain the PA-T3 Port Adapter

After configuring the new interface, you can display its status. To show current status of the T3 interface on the PA-T3 port adapter, perform any of the following tasks in EXEC mode:

Task	Command
Display system hardware configuration.	show version
Display current interface processors and their interfaces.	show controllers cbus
Display statistics for the T3 interface.	show interfaces slot/port-adapter/port (Cisco 7500 series and Cisco 7000 series routers with the RSP7000 and RSP7000CI) show interfaces slot/port (Cisco 7200 series)
Display the configuration information for the T3 interface.	show controllers serial slot/port-adapter/port (Cisco 7500 series and Cisco 7000 series routers with the RSP7000 and RSP7000CI) show controllers serial slot/port (Cisco 7200 series)
Display protocols configured for the system and specific interfaces.	show protocols
Display running configuration file.	show running-config
Display configuration stored in NVRAM.	show startup-config
Display specific port adapter information	show diag slot

Configuration Example

The following example shows a typical configuration for serial interface 1/0/0 on a PA-T3 serial port adapter in a Cisco 7500 series router. The dsu bandwidth command reduces the bandwidth by padding the T3 frame, and the dsu mode command enables and improves interoperability with other DSUs.

router# configure terminal

router(config)# interface serial 1/0/0

router(config-if)# ip address 1.1.1.10 255.255.255.0

router(config-if)# clock source internal

router(config-if)# crc 32

router(config-if)# dsu bandwidth 16000

router(config-if)# dsu mode 0

router(config-if)# no scramble

router(config-if)# framing c-bit

router(config-if)# no shutdown

router(config-if)# ^Z

Command Reference

This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 11.1 command references.

•cablelength

•clock source

•dsu bandwidth

•dsu mode

•framing

•invert data

•loopback

•scramble

•show controllers cbus

•show controllers serial

•show diag

•show interfaces serial

cablelength

To change the length of the cable, use the cablelength interface configuration command. To restore the default value, use the no form of this command.

cablelength length
no cablelength

Syntax Description

length

Cable length in the range of 0 to 450 feet. The default is 50 feet.

Default

50 feet

Command Mode

Interface configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 11.1 CA.

Example

The following example specifies a cable length of 250 feet:

interface serial 1/0

 cablelength 250

clock source

To control which clock a T3 interface or a PA-T3 serial port adapter will use to clock its transmitted data from, use the clock source interface configuration command. To restore the default value, use the no form of this command.

clock source {internal | line}
no clock source

Syntax Description

internal	Specifies that the interface will clock its transmitted data from its internal clock.
line	Specifies that the interface will clock its transmitted data from a clock recovered from the line's receive data stream (default).

Default

The line's receive data stream.

Command Mode

Interface configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 10.3.

This command was modified in Cisco IOS Release 11.1 CA to include the T3 serial port adapter and PA-T3 serial port adapter.

This command applies to a Cisco 4000 router or Cisco 7000 series, Cisco 7200 series, and Cisco 7500 series router. A T3 interface on a PA-T3 serial port adapter 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 T3 interface to clock its transmitted data from its internal clock:

interface serial 1/0

 clock source internal

dsu bandwidth

To specify the maximum allowable bandwidth used by the 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
no dsu bandwidth

Syntax Description

kbps	Maximum bandwidth in the range of 22 kbps to 44736 kbps. The default is 44736 kbps.

Default

44736 kbps

Command Mode

Interface configuration

Usage Guidelines

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 T3 frame.

To verify the data service unit (DSU) bandwidth configured on the interface, use the show controllers serial EXEC command.

Example

The following example sets the DSU bandwidth to 16000 kbps on interface 1/0/0:

interface serial 1/0/0

 dsu bandwidth 16000

Related Command

show controllers serial

dsu mode

To specify the interoperability mode used by the 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}
no dsu mode

Syntax Description

0	Sets the interoperability mode to 0. This is the default. Specify mode 0 to connect the 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 the PA-T3 port adapter to a Kentrox DSU.
2	Sets the interoperability mode to 2. Specify mode 2 to connect the PA-T3 port adapter to a Larscom DSU.

Default

0 mode

Command Mode

Interface configuration

Usage Guidelines

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 the PA-T3 port adapter. 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-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.

To verify the DSU mode configured on the interface, use the show controllers serial EXEC command.

Example

The following example sets the DSU mode to 1 on interface 1/0/0:

interface serial 1/0/0

 dsu mode 1

Related Command

show controllers serial

framing

To specify T3 line framing used by the PA-T3 port adapter, use the framing interface configuration command. To return to the default C-bit framing, use the no form of this command.

framing {c-bit | m13 | bypass}
no framing

Syntax Description

c-bit	Specifies C-bit T3 framing. This is the default.
m13	Specifies m13 T3 framing.
bypass	Specifies bypass T3 framing.

Default

C-bit framing

Command Mode

Interface configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 11.1 CA.

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 controllers serial EXEC command.

Example

The following example sets the framing mode to bypass on interface 1/0/0:

interface serial 1/0/0

 framing bypass

Related Command

show controllers serial

invert data

To invert the data stream, use the invert data interface configuration command. This command applies only to the Cisco 7000 series routers with the RSP7000 and RSP7000CI, Cisco 7200 series routers, and Cisco 7500 series routers. To disable this feature, use the no form of this command.

invert data
no invert data

Syntax Description

This command has no arguments or keywords.

Default

Data is not inverted.

Command Mode

Interface configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 11.1 CA and Release 11.2 P.

If the interface on the PA-T3 and PA-2T3 synchronous serial port adapters is used to drive a dedicated T3 line that does not have B8ZS encoding (a method to avoid 15 zeros), the data stream must be inverted (both TXD and RXD) either in the connecting CSU/DSU or the interface.

By inverting the HDLC data stream, the HDLC zero insertion algorithm becomes a ones insertion algorithm that satisfies the T3 requirements. Be careful not to invert data both on the interface and on the CSU/DSU as two data inversions will cancel each other out.

Inverting is a method of avoiding excessive zeroes that is superseded by the use of B8ZS encryption. This option could be needed for use with legacy equipment that supports this option.

Example

The following example inverts data on serial interface 3/1/0:

interface serial 3/1/0

 invert data

loopback

To loop the serial interface on a PA-T3 port adapter, use the loopback interface configuration command. To remove the loopback, use the no form of this command.

loopback {dte | local | network {line | payload} | remote}
no loopback

Syntax Description

dte	Sets the loopback after the LIU toward the terminal.
local	Sets the loopback after going through the framer toward the terminal.
network {line | payload}	Sets the loopback toward the network before going through the framer (line) or after going through the framer (payload).
remote	Sends a far-end alarm control (FEAC) to set the remote framer in loopback.

Default

Disabled

Command Mode

Interface configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 11.1 CA.

Use this command for troubleshooting purposes.

To verify that a loopback is configured on the interface, use the show interfaces serial EXEC command.

Example

The following example configures the serial interface located in slot 3/0/0 for a local loopback:

interface serial 3/0/0

 loopback local

Related Command

show interfaces serial

scramble

To enable scrambling of the payload on the PA-T3 port adapter, use the scramble interface configuration command. To disable scrambling, use the no form of this command.

scramble
no scramble

Syntax Description

This command has no keywords and arguments.

Default

Scrambling is disabled.

Command Mode

Interface configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 11.1 CA.

T3 scrambling is used to assist clock recovery on the receiving end.

Scrambling can prevent some bit patterns from being mistakenly interpreted as alarms by switches placed between the DSUs.

The local interface configuration must match the remote interface configuration. For example, if you enable scrambling on the local port, you must also do the same on the remote port.

To verify that scramble is configured on the interface, use the show controllers serial EXEC command.

Example

The following example enables scrambling on the PA-T3 port adapter in slot 1, port adapter slot 0, interface 0:

interface serial 1/0/0

 scramble

Related Command

show controllers serial

show controllers cbus

To display all of the current interface processors and their interfaces, use the show controllers cbus interface configuration command.

show controllers cbus

Syntax Description

This command has no keywords and arguments.

Command Mode

Interface configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 11.1 CA.

Sample Display

The following is sample output from the show controllers cbus command that shows serial port 1/0/0 on a 1-port T3 serial port adapter installed on a VIP2 in chassis slot 1 and serial port 2/0/0 on a 1-port E3 serial port adapter installed on a VIP2 in chassis slot 2:

router# show controllers cbus

MEMD at 40000000, 2097152 bytes (unused 672, recarves 1, lost 0)

  RawQ 48000100, ReturnQ 48000108, EventQ 48000110

  BufhdrQ 48000140 (2822 items), LovltrQ 48000158 (24 items, 2016 bytes)

  IpcbufQ 48000168 (40 items, 4096 bytes)

  IpcbufQ_classic 48000160 (8 items, 4096 bytes)

  3570 buffer headers (48002000 - 4800FF10)

  pool0: 10 buffers, 256 bytes, queue 48000148

  pool1: 439 buffers, 1536 bytes, queue 48000150

  pool2: 223 buffers, 4512 bytes, queue 48000170

  pool3: 4 buffers, 4544 bytes, queue 48000178

  slot0: VIP2, hw 2.4, sw 21.40, ccb 5800FF20, cmdq 48000080, vps 8192

    software loaded from system

    IOS (tm) VIP Software (SVIP-DW-M), Experimental Version 11.1(4430)

[gshen 108]

    ROM Monitor version 17.0

    Ethernet0/0/0, addr 00e0.f7d7.cb00 (bia 00e0.f7d7.cb00)

      gfreeq 48000150, lfreeq 48000180 (1536 bytes), throttled 4

      rxlo 4, rxhi 261, rxcurr 4, maxrxcurr 4

      txq 48001A00, txacc 48001A02 (value 146), txlimit 146

    Ethernet0/0/1, addr 00e0.f7d7.cb01 (bia 00e0.f7d7.cb01)

      gfreeq 48000150, lfreeq 48000188 (1536 bytes), throttled 0

      rxlo 4, rxhi 261, rxcurr 0, maxrxcurr 0

      txq 48001A08, txacc 48001A0A (value 0), txlimit 146

    Ethernet0/0/2, addr 00e0.f7d7.cb02 (bia 00e0.f7d7.cb02)

      gfreeq 48000150, lfreeq 48000190 (1536 bytes), throttled 0

      rxlo 4, rxhi 261, rxcurr 0, maxrxcurr 0

      txq 48001A10, txacc 48001A12 (value 0), txlimit 146

    Ethernet0/0/3, addr 00e0.f7d7.cb03 (bia 00e0.f7d7.cb03)

      gfreeq 48000150, lfreeq 48000198 (1536 bytes), throttled 0

      rxlo 4, rxhi 261, rxcurr 0, maxrxcurr 0

      txq 48001A18, txacc 48001A1A (value 0), txlimit 146

  slot1: VIP2, hw 2.4, sw 21.40, ccb 5800FF30, cmdq 48000088, vps 8192

    software loaded from system

    IOS (tm) VIP Software (SVIP-DW-M), Experimental Version 11.1(4430)

[gshen 108]

    ROM Monitor version 17.0

   Mx T3(1) HW Revision 0x3, FW Revision 2.55

    Serial1/0/0, applique is T3 DTE

      received clockrate 40557734

      gfreeq 48000170, lfreeq 480001A0 (4512 bytes), throttled 248

      rxlo 4, rxhi 222, rxcurr 2, maxrxcurr 4

      txq 48001A20, txacc 48001A22 (value 111), txlimit 111

  slot2: VIP2, hw 2.4, sw 21.40, ccb 5800FF40, cmdq 48000090, vps 8192

    software loaded from system

    IOS (tm) VIP Software (SVIP-DW-M), Experimental Version 11.1(4430)

[gshen 108]

    ROM Monitor version 17.0

   Mx E3(1) HW Revision 0x2, FW Revision 2.55

    Serial2/0/0, applique is E3 DTE

      received clockrate 48333264

      gfreeq 48000170, lfreeq 480001A8 (4512 bytes), throttled 0

      rxlo 4, rxhi 222, rxcurr 0, maxrxcurr 1

      txq 48001A28, txacc 48001A2A (value 111), txlimit 111

  slot3: VIP2, hw 2.4, sw 21.40, ccb 5800FF50, cmdq 48000098, vps 8192

    software loaded from system

    IOS (tm) VIP Software (SVIP-DW-M), Experimental Version 11.1(4430)

[gshen 108]

    ROM Monitor version 17.0

    Fddi3/0/0, addr 00e0.f7d7.cb60 (bia 00e0.f7d7.cb60)

      gfreeq 48000170, lfreeq 480001B0 (4512 bytes), throttled 0

      rxlo 4, rxhi 222, rxcurr 0, maxrxcurr 0

      txq 48001A30, txacc 48001A32 (value 111), txlimit 111

    FastEthernet3/1/0, addr 00e0.f7d7.cb68 (bia 00e0.f7d7.cb68)

      gfreeq 48000150, lfreeq 480001B8 (1536 bytes), throttled 0

      rxlo 4, rxhi 261, rxcurr 0, maxrxcurr 0

      txq 48001A38, txacc 48001A3A (value 0), txlimit 146

Related Command

show controllers serial

show controllers serial

Use the show controllers serial privileged EXEC command to display information that is specific to the interface hardware.

show controllers serial [slot/port]
show controllers serial [slot/port-adapter/port] (Cisco 7500 series and Cisco 7000 series
routers with the RSP7000 and RSP7000CI)

Syntax Description

slot	(Optional) Slot number of the interface.
port	(Optional) Port number on the interface. The port value is always 0.
port-adapter	(Optional) On Cisco 7500 series routers and Cisco 7000 series routers with the RSP7000 and RSP7000CI, the location of the port adapter on a VIP. The value can be 0 or 1.

Command Mode

Privileged EXEC

Usage Guidelines

This command first appeared in Cisco IOS Release 10.0.

This command was modified in Cisco IOS Release 11.1 CA to include sample output for the PA-T3 port adapter.

The information displayed is generally useful for diagnostic tasks performed by technical support personnel only. For the PA-T3, the show controllers serial command also displays configuration information such as the framing, clock source, bandwidth limit, whether scrambling is enabled, and DSU mode configured on the interface. Also displayed are the performance statistics for the current interval and last 15-minute interval and whether any alarms exist.

Sample Display

The following is sample output from the show controllers serial command that shows serial port 1/0/0 on a 1-port T3 serial port adapter installed on a VIP2 in chassis slot 1:

router# show controllers serial 2/0/1

Serial1/0/0 -

   Mx T3(1) HW Revision 0x3, FW Revision 2.55

   Framing is c-bit, Clock Source is Line

   Bandwidth limit is 35000, DSU mode 1, Cable length is 50

   Data in current interval (325 seconds elapsed):

     0 Line Code Violations, 0 P-bit Coding Violation

     0 C-bit Coding Violation

     0 P-bit Err Secs, 0 P-bit Sev Err Secs

     0 Sev Err Framing Secs, 0 Unavailable Secs

     0 Line Errored Secs, 0 C-bit Errored Secs, 0 C-bit Sev Err Secs

   Total Data (last 24 hours)

     0 Line Code Violations, 0 P-bit Coding Violation,

     0 C-bit Coding Violation,

     0 P-bit Err Secs, 0 P-bit Sev Err Secs,

     0 Sev Err Framing Secs, 0 Unavailable Secs,

     0 Line Errored Secs, 0 C-bit Errored Secs, 0 C-bit Sev Err Secs

No alarms detected.

show diag

To display hardware information for an interface, use the show diag privileged EXEC command on Cisco 7500 series routers.

show diag [slot]

Syntax Description

slot	(Optional) Slot number of the interface.

Command Mode

Privileged EXEC

Usage Guidelines

This command first appeared in Cisco IOS Release 11.1.

This command was modified in Cisco IOS Release 11.1 CA to include sample output for the PA-T3 port adapter.

Use this command to determine the type of port adapter installed on a VIP2 in your router.

Sample Display

The following is sample output from the show diag command for a one-port T3 serial port adapter in chassis slot 1:

router# show diag 1

Slot 1:

        Physical slot 1, ~physical slot 0xE, logical slot 1, CBus 0

        Microcode Status 0x4

        Master Enable, LED, WCS Loaded

        Board is analyzed

        Pending I/O Status: None

        EEPROM format version 1

        VIP2 controller, HW rev 2.4, board revision D0

        Serial number: 04372053  Part number: 73-1684-03

        Test history: 0x00        RMA number: 00-00-00

        Flags: cisco 7000 board; 7500 compatible

        EEPROM contents (hex):

          0x20: 01 15 02 04 00 42 B6 55 49 06 94 03 00 00 00 00

          0x30: 68 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

        Slot database information:

        Flags: 0x4      Insertion time: 0x14A8 (5d02h ago)

        Controller Memory Size: 16 MBytes DRAM, 1024 KBytes SRAM

        PA Bay 0 Information:

                T3 Serial PA, 1 ports

                EEPROM format version 1

                HW rev FF.FF, Board revision UNKNOWN

                Serial number: 4294967295  Part number: 255-65535-255

show interfaces serial

To display information about a serial interface, use the show interfaces serial privileged EXEC command.

show interfaces serial [slot/port] (Cisco 7200 series)
show interfaces serial [slot/port-adapter/port] (Cisco 7500 series and Cisco 7000 series with
the RSP7000 and RSP7000CI)

Syntax Description

slot	(Optional) Slot number of the interface.
port	(Optional) Port number on the interface. The port value is always 0.
port-adapter	(Optional) On Cisco 7500 series routers and Cisco 7000 series routers with the RSP7000 and RSP7000CI, the location of the port adapter on a VIP. The value can be 0 or 1.

Command Mode

Privileged EXEC

Usage Guidelines

This command was modified in Cisco IOS Release 11.1 CA to include sample output for the PA-T3 serial port adapter.

For additional command syntax and sample displays, refer to the show interfaces serial command in the "Interface Commands" chapter of the Configuration Fundamentals Command Reference.

Sample Displays

The following is sample output from the show interfaces serial command for a 1-port T3 serial port adapter-configured VIP2 in chassis slot 1, in port adapter slot 0.

router# show interface serial 1/0/0

Serial1/0/0 is up, line protocol is up

  Hardware is cyBus PODS3 Serial

  Internet address is 133.1.1.1/24

  MTU 4470 bytes, BW 44736 Kbit, DLY 200 usec, rely 255/255, load 1/255

  Encapsulation HDLC, loopback not set, keepalive set (10 sec)

  Last input 00:00:05, output 00:00:02, output hang never

  Last clearing of "show interface" counters 5d02h

  Queueing strategy: fifo

  Output queue 0/40, 0 drops; input queue 0/75, 27269 drops

  5 minute input rate 0 bits/sec, 0 packets/sec

  5 minute output rate 0 bits/sec, 0 packets/sec

     79039 packets input, 14195344 bytes, 0 no buffer

     Received 84506 broadcasts, 0 runts, 0 giants

              0 parity

     9574 input errors, 6714 CRC, 0 frame, 1 overrun, 0 ignored, 2859 abort

     62472 packets output, 13751644 bytes, 0 underruns

     0 output errors, 0 applique, 10 interface resets

     0 output buffer failures, 0 output buffers swapped out

     16 carrier transitions

   rxLOS inactive, rxLOF inactive, rxAIS inactive

   txAIS inactive, rxRAI inactive, txRAI inactive

describes significant fields shown in the display.

Table 2 Show Interfaces Serial Field Descriptions  

Field	Description
Serial... is {up | down} ...is administratively down	Indicates whether the interface hardware is currently active (whether carrier detect is present), inactive, or has been taken down by an administrator.
line protocol is {up | down}	Indicates whether the software processes that handle the line protocol consider the line usable (that is, whether keepalives are successful) or if it has been taken down by an administrator.
Hardware is	Specifies the hardware type.
Internet address is	Specifies the Internet address and subnet mask.
MTU	Maximum Transmission Unit of the interface.
BW	Indicates the value of the bandwidth parameter that has been configured for the interface (in kilobits per second). The bandwidth parameter is used to compute IGRP metrics only. If the interface is attached to a serial line with a line speed that does not match the default (1536 or 1544 for T1 and 56 for a standard synchronous serial line), use the bandwidth command to specify the correct line speed for this serial line.
DLY	Delay of the interface in microseconds.
rely	Reliability of the interface as a fraction of 255 (255/255 is 100% reliability), calculated as an exponential average over 5 minutes.
load	Load on the interface as a fraction of 255 (255/255 is completely saturated), calculated as an exponential average over 5 minutes.
Encapsulation	Encapsulation method assigned to interface.
loopback	Indicates whether loopback is set or not.
keepalive	Indicates whether keepalives are set or not.
Last input	Number of hours, minutes, and seconds since the last packet was successfully received by an interface. Useful for knowing when an interface failed.
Last output	Number of hours, minutes, and seconds since the last packet was successfully transmitted by an interface.
output hang	Number of hours, minutes, and seconds (or never) since the interface was last reset because of a transmission that took too long. When the number of hours in any of the "last" fields exceeds 24 hours, the number of days and hours is printed. If that field overflows, asterisks are printed.
Last clearing of "show interface" counters	Time the counters were last cleared.
Queueing strategy	First-in, first-out queuing strategy (other queueing strategies you might see are priority-list, custom-list, and weighted fair).
Output queue, drops input queue, drops	Number of packets in output and input queues. Each number is followed by a slash, the maximum size of the queue, and the number of packets dropped due to a full queue.
5 minute input rate 5 minute output rate	Average number of bits and packets transmitted per second in the last 5 minutes. The 5-minute input and output rates should be used only as an approximation of traffic per second during a given 5-minute period. These rates are exponentially weighted averages with a time constant of 5 minutes. A period of four time constants must pass before the average will be within two percent of the instantaneous rate of a uniform stream of traffic over that period.
packets input	Total number of error-free packets received by the system.
bytes input	Total number of bytes, including data and MAC encapsulation, in the error free packets received by the system.
no buffers	Number of received packets discarded because there was no buffer space in the main system. Compare with ignored count. Broadcast storms on Ethernets and bursts of noise on serial lines are often responsible for no input buffer events.
Received... broadcasts	Total number of broadcast or multicast packets received by the interface.
runts	Number of packets that are discarded because they are smaller than the medium's minimum packet size.
giants	Number of packets that are discarded because they exceed the medium's maximum packet size.
parity	Number of the parity errors on the interface.
input error	Total number of no buffer, runts, giants, CRCs, frame, overrun, ignored, and abort counts. Other input-related errors can also increment the count, so that this sum might not balance with the other counts.
CRC	Cyclic redundancy checksum generated by the originating station or far-end device does not match the checksum calculated from the data received. On a serial link, CRCs usually indicate noise, gain hits, or other transmission problems on the data link.
frame	Number of packets received incorrectly having a CRC error and a noninteger number of octets. On a serial line, this is usually the result of noise or other transmission problems.
overrun	Number of times the serial receiver hardware was unable to hand received data to a hardware buffer because the input rate exceeded the receiver's ability to handle the data.
ignored	Number of received packets ignored by the interface because the interface hardware ran low on internal buffers. Broadcast storms and bursts of noise can cause the ignored count to be increased.
abort	Illegal sequence of one bits on a serial interface. This usually indicates a clocking problem between the serial interface and the data link equipment.
packets output	Total number of messages transmitted by the system.
bytes output	Total number of bytes, including data and MAC encapsulation, transmitted by the system.
underruns	Number of times that the transmitter has been running faster than the router can handle. This might never be reported on some interfaces.
output errors	Sum of all errors that prevented the final transmission of datagrams out of the interface being examined. Note that this might not balance with the sum of the enumerated output errors, as some datagrams might have more than one error, and others might have errors that do not fall into any of the specifically tabulated categories.
applique	Indicates an unrecoverable error has occurred on the T3 applique. The router then invokes an interface reset.
interface resets	Number of times an interface has been completely reset. This can happen if packets queued for transmission were not sent within several seconds' time. On a serial line, this can be caused by a malfunctioning modem that is not supplying the transmit clock signal, or by a cable problem. If the system notices that the carrier detect line of a serial interface is up, but the line protocol is down, it periodically resets the interface in an effort to restart it. Interface resets can also occur when an interface is looped back or shut down.
output buffer failures	Number of no resource errors received on the output.
output buffers swapped out	Number of packets swapped to DRAM.
carrier transitions	Number of times the carrier detect signal of a serial interface has changed state. For example, if data carrier detect (DCD) goes down and comes up, the carrier transition counter will increment two times. Indicates modem or line problems if the carrier detect line is changing state often.
rxLOS, rxLOF, rxAIS	Receive loss of signal, loss of frame, and alarm indication signal status. Values are inactive or active.
txAIS, rxRAI, txRAI	Transmit alarm indication signal, receive remote alarm indicator, and transmit remote alarm indicator status. Values are inactive or active. When the router receives an LOS, LOF, or AIS, the txRAI is active. When the remote router receives an LOS, LOF, or AIS, the rxRAI is active.

Supported MIB

The PA-T3 port adapter supports a subset of RFC 1407 MIB.

We support DS3 Near End Group including—DS3/T3 Configuration Table, DS3/T3 Current Table, DS3/T3 Interval Table, and DS3/T3 Total Table.

We do not support DS3 Far End Group and DS3/T3 Fractional Group.

The PA-T3 port adapter also supports the cardTable in the Cisco Chassis MIB and the MIB-II for each PA-T3 interface.

What to Do Next

For more information on the PA-T3 serial port adapter, refer to the PA-T3 Serial Port Adapter Installation and Configuration publication.