Chapter 4: Configuring the 6E3 Line Card

Table Of Contents

Configuring the 6E3 Line Card

Using the EXEC Command Interpreter

Configuring the Interfaces

Shutting Down an Interface

Performing a Basic Configuration

Customizing the 6E3 Line Card Configuration

Checking the Configuration

Using show Commands to Verify the New Interface Status

E3 Alarm and Event Detection

Using the ping Command to Verify Network Connectivity

Using loopback Commands

Bit Error Rate Testing

CLI-Controlled OIR

Line Card Crash Recovery

DSU Link Doesn't Work

Symptom

Conditions

Workaround

Configuring the 6E3 Line Card

To continue your 6E3 line card installation, you must configure the serial interfaces.

This chapter contains the following sections:

• Using the EXEC Command Interpreter

• Configuring the Interfaces

• Checking the Configuration

• CLI-Controlled OIR

• Line Card Crash Recovery

• DSU Link Doesn't Work

Using the EXEC Command Interpreter

You modify the configuration of your router through the software command interpreter called the EXEC (also called enable mode). You must enter the privileged level of the EXEC command interpreter with the enable command before you can use the configure command to configure a new interface or change the existing configuration of an interface. The system prompts you for a password if one has been set.

The system prompt for the privileged level ends with a pound sign (#) instead of an angle bracket (>). At the console terminal, use the following procedure to enter the privileged level:

Step 1 At the user-level EXEC prompt, enter the enable command. The EXEC prompts you for a privileged-level password as follows:
Router> enablePassword:
Step 2 Enter the password (the password is case sensitive). For security purposes, the password is not displayed.

When you enter the correct password, the system displays the privileged-level system prompt (#):
Router#

To configure the new interfaces, proceed to the "Configuring the Interfaces" section.

Configuring the Interfaces

After you verify that the new 6E3 line card is installed correctly (the STATUS LED turns green), use the privileged-level configure command to configure the new interfaces. Have the following information available:

•E3 information such as clock source and framing type

•Protocols you plan to route on each new interface

•IP addresses, if you plan to configure the interfaces for IP routing

•Bridging protocols you plan to use

•Timing source for each new interface

If you installed a new 6E3 line card or if you want to change the configuration of an existing interface, you must enter configuration mode to configure the new interfaces. If you replaced a 6E3 line card that was previously configured, the system recognizes the new interfaces and brings each of them up in their existing configuration.

For a summary of the configuration options available and instructions for configuring interfaces on a 6E3 line card, refer to the appropriate configuration publications listed in the "Related Documentation" section on page viii.

You execute configuration commands from the privileged level of the EXEC command interpreter, which usually requires password access. Contact your system administrator, if necessary, to obtain password access. (See the "Using the EXEC Command Interpreter" section for an explanation of the privileged level of the EXEC.)

This section contains the following subsections:

• Shutting Down an Interface

• Performing a Basic Configuration

• Customizing the 6E3 Line Card Configuration

Shutting Down an Interface

Before you remove an interface that you will not replace, or replace line cards, use the shutdown command to shut down (disable) the interfaces to prevent anomalies when you reinstall the new interface processor. When you shut down an interface, it is designated administratively down in the show command displays.

Follow these steps to shut down an interface:

Step 1 Enter the privileged level of the EXEC command interpreter (also called enable mode). (See the "Using the EXEC Command Interpreter" section for instructions.)

Step 2 At the privileged-level prompt, enter configuration mode and specify that the console terminal is the source of the configuration subcommands, as follows:
Router# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)#

Step 3 Shut down interfaces by entering the interface serial subcommand (followed by the interface address of the interface), and then enter the shutdown command. Table 4-1 shows the command syntax.

When you have finished, press Ctrl-Z—hold down the Control key while you press Z—or enter end or exit to exit configuration mode and return to the EXEC command interpreter.

Table 4-1 Syntax of the shutdown Command

Platform

Command

Example

Cisco 7304 routers

interface, followed by the type (serial) and slot/port (slot-number/
interface-port-number)

The example is for interface 0 and interface 1 on a 6E3 line card in slot 2.
Router(config-if)# interface serial 2/0Router(config-if)# shutdownRouter(config-if)# interface serial 2/1Router(config-if)# shutdownCtrl-ZRouter#

Note If you need to shut down additional interfaces, enter the interface serial command (followed by the interface address of the interface) for each of the interfaces on your line card. Use the no shutdown command to enable the interface.

Step 4 Write the new configuration to NVRAM as follows:
Router# copy running-config startup-config[OK]Router#

The system displays an OK message when the configuration has been stored in NVRAM.

Step 5 Verify that new interfaces are now in the correct state (shut down) using the show interfaces command (followed by the interface type and interface address of the interface) to display the specific interface. Table 4-2 provides examples.

Table 4-2 Examples of the show interfaces serial Command

Platform

Command

Example

Cisco 7304 router

show interfaces serial, followed by slot/port (slot-number/
interface-port-number)

The example is for interface 0 on a 6E3 line card in slot 2.
Router# show interfaces serial 2/0
Serial 2/0 is administratively down, line protocol is down

Step 6 Reenable interfaces by doing the following:

a. Repeat Step 3 to reenable an interface. Substitute the no shutdown command for the shutdown command.

b. Repeat Step 4 to write the new configuration to memory.
Use the copy running-config startup-config command.

c. Repeat Step 5 to verify that the interfaces are in the correct state. Use the
show interfaces command followed by the interface type and interface address of the interface.

For complete descriptions of software configuration commands, refer to the publications listed in the "Related Documentation" section on page viii.

Performing a Basic Configuration

Following are instructions for a basic configuration: enabling an interface and specifying IP routing. You might also need to enter other configuration subcommands, depending on the requirements for your system configuration and the protocols you plan to route on the interface. For complete descriptions of configuration subcommands and the configuration options available for serial interfaces, refer to the appropriate software documentation.

In the following procedure, press the Return key after each step unless otherwise noted. At any time you can exit the privileged level and return to the user level by entering disable at the prompt as follows:
Router# disable
Router>

Step 1 Enter configuration mode and specify that the console terminal is the source of the configuration subcommands, as follows:
Router# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)#

Step 2 Specify the first interface to configure by entering the interface serial subcommand, followed by the interface address of the interface you plan to configure. Table 4-3 provides an example.

Table 4-3 Examples of the interface serial Subcommand

Platform

Command

Example

Cisco 7304 router

interface serial, followed by slot/port (slot-number/
interface-port-number)

The example is for the first interface of a 6E3 line card in slot 4.
Router(config)# interface serial 4/0Router(config-if)#

Step 3 Assign an IP address and subnet mask to the interface (if IP routing is enabled on the system) by using the ip address subcommand, as in the following example:
Router(config-if)# ip address 10.0.0.0 10.255.255.255

Step 4 Add any additional configuration subcommands required to enable routing protocols and set the interface characteristics.

Step 5 Reenable the interfaces using the no shutdown command. (See the "Shutting Down an Interface" section.)

Step 6 Configure all additional line card interfaces as required.

Step 7 After including all of the configuration subcommands to complete your configuration, press Ctrl-Z—hold down the Control key while you press Z—or enter end or exit to exit configuration mode and return to the EXEC command interpreter prompt.

Step 8 Write the new configuration to NVRAM as follows
Router# copy running-config startupup-config[OK]Router#

This completes the procedure for creating a basic configuration.

Table 4-4 shows the default values for the 6E3 line card serial interfaces.

Table 4-4 6E3 Line Card Serial Interface Default Values

Parameter

Configuration Command

Default Value

Clock source

clock source [internal | line]

line

Cyclic redundancy check

crc [16 | 32]

16

DSU mode

[no] dsu mode [cisco | digital-link | kentrox]

cisco

DSU subrate bandwidth

[no] dsu bandwidth kbps

34010

Encapsulation

encapsulation [frame-relay | hdlc | ppp]

hdlc

Idle character mode

[no] idle-character [flags | marks]

flags

Invert data

[no] invert data

no invert data

Keepalive

[no] keepalive [seconds]

keepalive 10

Loopback mode

[no] loopback [local | network line | network payload | dte]

no loopback

Maximum transmission unit

[no] mtu bytes

4470 bytes

National bit

[no] national bit [0 | 1]

0

Payload scrambling

[no] scramble

no scramble

Transmitter delay

[no] transmitter-delay # of idle characters

0-255

Customizing the 6E3 Line Card Configuration

There are two sides to the network, a local network side and a remote customer side, or near and far ends. The 6E3 line card supports third-party data service units (DSUs), Internet Service Provider (ISP)-provided E3 lines, and so on. The configuration parameter default values in the 6E3 line card port interfaces must match the remote DSUs on your network. Table 4-5 shows the configuration parameters.

Table 4-5 6E3 Line Card Serial Interface DSU Modes

Parameter

Configuration Command

Default Value

Command

DSU mode

[no] dsu mode [cisco | digital-link | kentrox]

cisco

Router(config-if)# dsu mode cisco

DSU subrate bandwidth

[no] dsu bandwidth kbps

34010

Router(config-if)# dsu bandwidth 34010

Payload scrambling

[no] scramble

no scramble

Router(config-if)# scramble

Cyclic redundancy check

crc [16 | 32]

16

Router(config-if)# crc 16

Note The local port and the remote port must have matching configurations.

Verifying Local and Remote E3 Port Settings

You can use telnet to determine the DSU mode settings on the remote E3 port. Once you verify the remote E3 port settings, you can negotiate changing configuration parameters so that DSU mode settings are the same on both the local and remote E3 ports.

Selecting a DSU Mode

The DSU mode supports two third-party DSU vendors—Digital Link and Kentrox—and the default DSU mode, Cisco. If you use a DSU to make the connection between the Cisco 7304 router and another device, the local E3 port configuration must match the remote E3 port configuration. Therefore, if the remote E3 port uses the Kentrox vendor, a request is sent to the local E3 port to change the DSU mode to Kentrox, either by manually entering the dsu mode configuration command and specifying the Kentrox DSU or by using the Cisco Remote Connection Management (CRCM) feature to remotely configure the remote E3 port. If you make a direct connection between a Cisco 7304 router and another device, you can use the Cisco DSU mode.

Configuring the DSU Bandwidth Range

The DSU bandwidth range is from 0 to 34010 kbps. The local port and the remote port must have matching configurations. Therefore, if you reduce the effective bandwidth to 3000 on the local port, you must do the same on the remote port by entering the dsu bandwidth interface configuration command.

In interface configuration mode, reduce effective bandwidth (range of 0 to 34010 kbps) by entering the dsu bandwidth configuration subcommand, as in the following example:
Router(config-if)# dsu bandwidth 3000

Use the no form of this command to return to the default, 34010.

Note The local port configuration must match the remote port configuration.

Enabling Payload Scrambling

Payload (data) scrambling converts the data received by the local or remote E3 ports from the Digital Link and Kentrox third-party DSU vendor modes as well as the default, Cisco mode. To enable payload scrambling on the local and remote E3 ports, you must enter the scramble interface configuration command. If you do not enter the scramble command, payload scrambling remains disabled by default on the local and remote E3 ports.

Configuring Cyclic Redundancy Checks

Table 4-6 summarizes cyclic redundancy check (CRC) commands. For more information, see the remainder of this section.

Table 4-6 CRC Commands

Purpose

Command

Example

Enable 32-bit CRC

crc size

The example enables 32-bit CRC on a serial interface:
Router(config)# interface serial 3/0Router(config-if)# crc 32

Return to default 16-bit CRC

no crc size

The example disables 32-bit CRC on a serial interface and returns to the default 16-bit CRC:
Router(config)# interface serial 3/0Router(config-if)# no crc 32

CRC is an error-checking technique that uses a calculated numeric value to detect errors in transmitted data. All interfaces use a 16-bit CRC by default but also support a 32-bit CRC. The sender of a data frame calculates the frame check sequence (FCS). Before it sends a frame, the sender appends the FCS value to the message. The receiver recalculates the FCS and compares its calculation to the FCS from the sender. When the CRC on a received frame is not correct, the frame is dropped. The card does not send a request to the remote end to transmit the frame. (A higher layer protocol is required to implement the retransmission.)

Enable 32-bit CRC using the crc 32 command. Before you can enable 32-bit CRC, you must use the interface serial command (followed by the interface address of the interface) to select the interface on which you want to enable 32-bit CRC. This command functions in the same way on all supported platforms.

In the example that follows, 32-bit CRC is specified:
Router(config-if)# crc 32

The preceding command example applies to all systems in which the 6E3 line card is supported.
Use the no crc 32 command to disable the 32-bit CRC setting and return the interface to the default 16-bit CRC setting.

When you have finished, press Ctrl-Z—hold down the Control key while you press Z—or enter end or exit to exit configuration mode and return to the EXEC command interpreter prompt. Then write the new configuration to NVRAM using the copy running-config startup-config command.

Note When enabling a 16-bit or 32-bit CRC on a local interface, ensure that the remote device is also configured for a 16-bit or 32-bit CRC.

For command descriptions, refer to the Configuration Fundamentals Configuration Guide publication. For more information, see the "Obtaining Additional Publications and Information" section on page xi and the "Obtaining Additional Publications and Information" section on page xi.

Configuring the Clock Source

The only exception for matching local and remote E3 port configurations is that the clock sources must be set opposite each other. Therefore, if you enter the clock source internal command for the local E3 port, you must enter clock source line for the remote E3 port.

Defining the DSU Mode

In interface configuration mode, define the DSU interoperability mode by entering the dsu mode [cisco | digital-link | kentrox ] configuration subcommand, as in the following example:
Router(config-if)# dsu mode cisco

Use the no form of this command to return to the default, cisco.

Note The local port configuration must match the remote port configuration. For example, if you define the DSU interoperability mode as cisco on the local port, you must do the same on the remote port. You need to know what type of DSU is at the remote port to find out if it interoperates with the 6E3 line card. For E3 serial interfaces, specify cisco for connection from a 6E3 line card to another 6E3 line card. Specify digital-link for connection to a Digital Link DSU (DL3100). Specify kentrox for connection from a 6E3 line card to a Kentrox DSU.

Also see the "Interoperability Guidelines for 6E3 Line Card DSUs" section on page 1-3 for information regarding DSU feature compatibilities.

Enabling E3 Scrambling

In interface configuration mode, enable E3 scrambling by entering the scramble configuration subcommand, as in the following example:
Router(config-if)# scramble

Use the no form of this command to restore the default value, scramble.

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

Also see the "Interoperability Guidelines for 6E3 Line Card DSUs" section on page 1-3 for information regarding DSU feature compatibilities.

Checking the Configuration

After configuring the new interface, use the show commands to display the status of the new interface or all interfaces, and use the ping and loopback commands to check connectivity. This section includes the following subsections:

• Using show Commands to Verify the New Interface Status

• E3 Alarm and Event Detection

• Using the ping Command to Verify Network Connectivity

• Using loopback Commands

• Bit Error Rate Testing

Using show Commands to Verify the New Interface Status

Table 4-7 demonstrates how you can use the show commands to verify that new interfaces are configured and operating correctly and that the 6E3 line card appears in them correctly. Sample displays of the output of selected show commands appear in the sections that follow. For complete command descriptions and examples, refer to the publications listed in the "Related Documentation" section on page viii.

Note The outputs that appear in this document may not match the output you receive when running these commands. The outputs in this document are examples only.

Table 4-7 Using show Commands

Command

Function

Example

show version

Displays system Cisco IOS software version, names and sources of configuration files, and boot images
Router# show version

show controllers

Displays all the current E3 interfaces
Router# show controllers

show diag slot

Displays types of line cards installed in your system and information about a specific chassis slot
Router# show diag 2

show interfaces type slot-number/
interface-port-number

Displays status information about a specific type of interface (for example, serial) in a Cisco 7304 router
Router# show interfaces serial 2/0

show protocols

Displays protocols configured for the entire system and for specific interfaces
Router# show protocols

show running-config

Displays the running configuration file
Router# show running-config

show startup-config

Displays the configuration stored in NVRAM
Router# show startup-config

If an interface is shut down and you configured it as up, or if the displays indicate that the hardware is not functioning properly, ensure that the interface is properly connected and terminated. If you still have problems bringing up the interface, contact a service representative for assistance. This section includes the following subsections:

• Using the show version Command

• Using the show diag (slot) Command

• Using the show interfaces Command

Choose the subsection appropriate for your system. Proceed to the "Using the ping Command to Verify Network Connectivity" section when you have finished using the show commands.

Using the show version Command

Display the configuration of the hardware, the Cisco IOS software version, the names and sources of configuration files, and the boot images by using the show version command.

Note The outputs that appear in this document may not match the output you receive when running these commands. The outputs in this document are examples only.

Cisco 7304 Routers

Following is an example of the show version command from a Cisco 7304 router with the 6E3 line card:
WS_2_DS3_1600 #show version
Cisco Internetwork Operating System SoftwareIOS (tm) 7300 Software (C7300-JS-M), Version 12.2(20S)Copyright (c) 1986-2001 by cisco Systems, Inc.Compiled Thu 20-Dec-03 03:25 by cvaImage text-base:0x4000878, data-base:0x42794000
ROM:System Bootstrap, Version 12.1(12r)EX1,RELEASE SOFTWARE (fc1)Currently running ROMMON from ROM 0
WS_@_DS3_1600 uptime is 3 hours, 50 minutesSystem returned to ROM by reloadSystem image file is "disk0:c7300-js-mz
cisco 7300 (NSE100) processor (revision E) with 114688K/16384K bytes of memory.Processor board ID SCA0702004VR7000 CPU at 350Mhz, Implementation 39, Rev 3.2, 256KB L2, 1024KB L3 Cache4 slot midplane, Version 67.49
Last reset from software reset or reloadBridging software.X.25 software, Version 3.0.0.SuperLAT software (copyright 1990 by Meridian Technology Corp).TN3270 Emulation software.PXF processor tmc0 running 'system:pxf/ucode1' v1.4 is activePXF processor tmc1 running 'system:pxf/ucode1' v1.4 is active1 FastEthernet/IEEE 802.3 interface(s)2 Gigabit Ethernet/IEEE 802.3 interface(s)12 Serial network interface(s)1 Packet over Sonet network interface(s)509K bytes of non-volatile configuration memory.
16064K bytes of ATA compact flash in bootdisk (Sector size 512 bytes).31360K bytes of ATA compact flash in disk0 (Sector size 512 bytes).Configuration register is 0x0

Using the show diag (slot) Command

Display the types of line cards installed in your system (and specific information about each) using the show diag slot command.

Note The outputs that appear in this document may not match the output you receive when running these commands. The outputs in this document are examples only.

Cisco 7304 Routers

Following is an example of the show diag slot command that shows the 6E3 line card in slot 2 of a Cisco 7304 router:
Router# show diag 2
Slot 2:E3 Line Card, 6 portsLine Card state:ActiveInsertion time:23:39:27 agoBandwidth points:204060EEPROM contents at hardware discovery:Hardware Revision :3.0Unknown Field (type 0046):00 00PCB Serial Number :CAB0548LLN5Part Number :73-5938-04Board Revision :A0Fab Version :02RMA Test History :00RMA Number :0-0-0-0RMA History :00Deviation Number :0-0Product Number :7300-6E3Top Assy. Part Number :68-0000-00Manufacturing Test Data :00 00 00 00 00 00 00 00Field Diagnostics Data :00 00 00 00 00 00 00 00Calibration Data :Minimum:0 dBmV, Maximum:0 dBmVCalibration values :EEPROM format version 4EEPROM contents (hex):0x00:04 FF 40 03 E2 41 03 00 46 00 00 C1 8B 43 41 420x10:30 35 34 38 4C 4C 4E 35 82 49 17 32 04 42 41 300x20:02 02 03 00 81 00 00 00 00 04 00 80 00 00 00 000x30:CB 94 37 33 30 30 2D 36 45 33 20 20 20 20 20 200x40:20 20 20 20 20 20 87 44 00 00 00 C4 08 00 00 000x50:00 00 00 00 00 C5 08 00 00 00 00 00 00 00 00 C80x60:09 00 00 00 00 00 00 00 00 00 C7 7C F6 49 44 350x70:00 00 00 00 00 00 00 00 00 00 00 00 07 08 64 320x80:28 37 26 09 C4 64 32 28 32 DD 0C E4 64 32 28 430x90:24 2E E0 AA 82 64 F4 24 00 00 00 00 00 00 00 000xA0:00 00 00 00 00 00 F4 B9 FF FF FF FF FF FF FF FF0xB0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0xC0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0xD0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0xE0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0xF0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x100:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x110:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x120:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x130:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x140:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x150:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x160:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x170:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x180:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x190:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x1A0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x1B0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x1C0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x1D0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x1E0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF0x1F0:FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FFFPGA information:Current FPGA version :00.16IOS bundled FPGA version :00.16CPLD version :01.02LC recoveries happened so far:1LC Crash History:LC 2, LC Santa Ana, channel A, error counters:SL0 SL1 SL2 SL3Reframe: [ 0 0 0 0 ]Overrun: [ 0 0 0 0 ]Underrun: [ 0 0 0 0 ]OOB: [ 0 0 0 0 ]Disparity: [ 0 0 0 0 ]Missing_Ctrl_Code: [ 0 0 0 0 ]Chip access errors:[ 0 0 0 0 ]LC 2, NSE Santa Ana 0, channel A, error counters:SL0 SL1 SL2 SL3Reframe: [ 0 0 0 0 ]Overrun: [ 0 0 0 0 ]Underrun: [ 0 0 0 0 ]OOB: [ 0 0 0 0 ]Disparity: [ 0 0 0 0 ]Missing_Ctrl_Code: [ 0 0 0 0 ]Chip access errors:[ 0 0 0 0 ]
Linecard interrupt counters:Egress droped packet = 11 (23:41:58 ago)Alarms = 30 (23:56:13 ago)Egress hw error = 10 (23:41:58 ago)Linecard egress hardware error counters:Pkt buffer invalid i/p hdr = 10 (23:41:58 ago)No sop flag at the packet hdr = 4 (23:44:24 ago)Port id error = 10 (23:41:58 ago)
Router#
Using the show interfaces Command

The show interfaces command displays status information (including the physical slot and interface address) for the interfaces you specify. The example that follows specifies serial interfaces.

Note The outputs that appear in this document may not match the output you receive when running these commands. The outputs in this document are examples only.

Cisco 7304 Routers

Following is an example of the show interfaces command for Cisco 7304 routers. In this example, the serial interfaces (0 to 5) are on a 6E3 line card in slot 1, also, the status information for interfaces 1 through 5 is omitted. (Interfaces are administratively shut down until you enable them.)
Router #sho interfaces serial 2/1Serial2/1 is up, line protocol is upHardware is Packet over E3Internet address is 150.2.2.1/24MTU 4470 bytes, BW 34009 Kbit, DLY 200 usec,reliability 255/255, txload 1/255, rxload 1/255Encapsulation HDLC, crc 16, loopback setKeepalive not setLast input 21:04:19, output 21:04:19, output hang neverLast clearing of "show interface" counters 16:31:30Input queue:0/75/0/0 (size/max/drops/flushes); Total output drops:15263Queueing strategy:fifoOutput queue:0/40 (size/max)5 minute input rate 0 bits/sec, 0 packets/sec5 minute output rate 0 bits/sec, 0 packets/sec0 packets input, 0 bytes, 0 no bufferReceived 0 broadcasts (0 IP multicast)0 runts, 0 giants, 0* throttles0 parity0 input errors, 0 CRC, 0 frame, 0 overrun,, 0 abort505603671 packets output, 48537952992 bytes, 0 underruns0 output errors, 0 applique, 0 interface resets0 output buffer failures, 0 output buffers swapped out0 carrier transitions(Additional display test omitted from this example.)
E3 Alarm and Event Detection

This section assumes that you are familiar with E3 alarms and line states. The 6E3 line card does not have an LED for alarm and event detection. However, you can enter the show controllers serial slot/port EXEC command to verify whether the alarm and event detection messages are active or inactive. Most alarm and event detection messages are short-lived, because if problems occur, the line card clears the error condition, but records the event to verify line card operation status.

The output from the show controllers serial slot/port EXEC command sends messages about the following types of alarms and events:

•AIS (Alarm Indication Signal)

•LOF (Loss of Frame)

•LOS (Loss of Signal)

•RAI (Remote Alarm Indication)

•OOF (Out of Frame)

Cisco 7304 Routers

The output also indicates whether the alarm or event originates from the local-end connector or the remote-end connector, as shown in the following example:
WS_2_DS3_1600 #show controllers serial 2/0Interface Serial2/0 (E3 port 0)Line state is uprxLOS inactive, rxLOF inactive, rxAIS inactivetxAIS inactive, rxRAI inactive, txRAI inactiveCurrent configurable parameter settings:Loopback is none,Clock source is internalDSU mode is cisco, DSU bandwidth limit is 34010National bit is 0Payload scrambling is disabled, CRC is 32Bert pattern is disabled, Bert interval is 0 minutesTransmitter delay is 0, Encapsulation is HDLCIdle character is flags, Invert data is disabledMTU is 9216MIB information:Data in current interval (477 seconds elapsed):0 Line Code Violations0 P-bit Err Secs, 0 P-bit Sev Err Secs0 Sev Err Framing Secs, 0 Unavailable Secs0 Line Errored SecsNo alarms detected.Interface 2/0 counters:Total input packets = 804690023, bytes = 77792437916, drops = 0Total output packets = 816580774, bytes = 78921469092, drops = 0PXF i/f number = 0x10PXF Hdr lo = 0x3000012, PXF Hdr hi = 0x1000000

Using the ping Command to Verify Network Connectivity

Using the ping command, you can verify that an interface port is functioning properly. This section provides a brief description of this command. Refer to the publications listed in the "Related Documentation" section on page viii for detailed command descriptions and examples.

The ping command sends echo request packets out to a remote device at an IP address that you specify. After sending an echo request, the system waits a specified time for the remote device to reply. Each echo reply is displayed as an exclamation point (!) on the console terminal; each request that is not returned before the specified timeout is displayed as a period (.). A series of exclamation points (!!!!!) indicates a good connection; a series of periods (.....) or the messages [timed out] or [failed] indicate a bad connection.

Following is an example of a successful ping command to a remote server with the address 10.0.0.10:
Router# ping 10.0.0.10 <Return>Type escape sequence to abort.Sending 5, 100-byte ICMP Echoes to 10.0.0.10, timeout is 2 seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 1/15/64 msRouter#

If the connection fails, verify that you have the correct IP address for the destination and that the device is active (powered on), and repeat the ping command.

Proceed to the next section, " Using loopback Commands," to finish checking network connectivity.

Using loopback Commands

With the loopback test, you can detect and isolate equipment malfunctions by testing the connection between the 6E3 line card interface and a remote device such as a modem or a CSU/DSU. The loopback command places an interface in loopback mode, which enables test packets that are generated from the ping command to loop through a remote device or compact serial cable. If the packets complete the loop, the connection is good. If not, you can isolate a fault to the remote device or compact serial cable in the path of the loopback test.

Table 4-8 provides examples of the loopback {dte | local | network {line | payload} command. The examples given are for interface 0 of a 6E3 line card in slot 2 of a Cisco 7304 router:

Table 4-8 Using loopback Commands

Command

Function

Example

loopback local

Sets the interface into local loopback mode. Local loopback loops the router output data back toward the router at the framer.
Router(config)# interface serial 2/0Router(config-if)# loopback local

loopback network line

Sets the interface into network line loopback mode. Network line loopback loops the data back toward the network (before the framer).
Router(config)# interface serial 2/0Router(config-if)# loopback network line

loopback network payload

Sets the interface into network payload loopback mode. Network payload loopback loops just the payload data back toward the network at the E3 framer.
Router(config)# interface serial 2/0Router(config-if)# loopback network payload

loopback dte

Sets the interface into loopback data terminal equipment (DTE) mode. Loopback DTE loops the router output data back toward the router (after the LIU).
Router(config)# interface serial 2/0Router(config-if)# loopback dte

Figure 4-1 shows the data flow for three loopback configuration paths, including no loopback.

Figure 4-1 E3 Loopback Paths

Bit Error Rate Testing

The ratio of received bits on an interface that contain errors is called the bit error rate (BER). A bit error rate test (BERT) is used to check the BER. E3 bit error rate testing is used on the Cisco 7304 router to check communication between local and remote E3 ports. If traffic is not being transmitted or received on an E3 port, or if the quality of the line simply needs to be tested, E3 bit error rate testing can be used to test the port.

For information on performing bit error rate testing, refer to the Configuration Tasks section of the T3 Maintenance Data Link Messages on the Cisco 7304 Router documenat the following URL:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121newft/121limit/121ex/121ex12c/e_t3bert.htm#1023406

CLI-Controlled OIR

Line cards can be removed from the Cisco 7304 router without disrupting data flow by using the hw-module slot slot # stop/start command in EXEC mode. The hw-module slot slot # stop command will stop traffic, shut down all line card interfaces, and deactivate the line card. The hw-module slot slot # start command resets the line card, puts the line card back online and turns off the OIR LED.

Note Upon insertion of a line card, the system will automatically activate the card. The hw-module slot slot # start command is only necessary when reactivating an installed line card that has been deactivated with the hw-module slot slot # stop command.

To remove and install an active line card in slot 2 proceed as follows:

Step 1 Enter the following:
Router# hw-module slot 2 stop

Step 2 When the OIR LED turns green, remove the line cards from slot 2.

When the OIR LED turns green, the line card in slot 2 has been deactivated and can be physically removed and replaced with a new line card (see the "Line Card Removal and Installation" section on page 3-3).

Step 3 Insert the new line card in slot 2. It is automatically reset, put online, and the OIR LED is turned off.

Line Card Crash Recovery

The 6E3 line card automatically recovers from the following catastrophic errors:

•Fatal serial link errors

•Line card local processor firmware crash

•Loss of keepalive packets from line card local processor

•Hardware errors reported by line card devices

•Too many line card error interrupts (more than 60 interrupts within 10 processor ticks)

If the 6E3 line card encounters more than five fatal errors within one hour, recovery will not be attempted and the line card will be deactivated. To reactivate the line card use the hw-module slot slot # start command, or physically remove and replace the line card.

The 6E3 line card crash history may be viewed by using the show diag slot command. The crash history is saved as long as the line card is physically present in the chassis. Physically removing the 6E3 line card from the chassis or performing a CLI-controlled OIR will clear the crash history.

The following messages are associated with line card recovery:
Error Message 00:00:06:% LC-3-RECOVERY: Line card (slot <x>) recovery in progress Error Message 00:00:06:% LC-3-EXCESSERRORS: Errors seen on the line card (slot %d) exceeds the error threshold
When the 6E3 line card encounters any of the nonrecoverable errors listed below, the line card is deactivated and must be restarted by performing a CLI-controlled OIR or physically removing and installing the line card.

•Line card hardware failures

•Line card local processor boot code/firmware initialization failure (failure to boot or boot code exceptions, firmware download failure)

•Environmental critical conditions (voltage and temperature)

•Insufficient system memory to allocate critical line card driver data structures during line card initialization

The following examples show nonrecoverable fatal error messages:
Error Message 00:00:06% SERIAL-0-DLL_OUTOFLOCK: E3 HW DLLS failed to lock in line card at slot <x> Error Message 00:00:06% SERIAL-0-860_BOOT_NOTOK: E3 Line card local processor at slot <x> failed to boot Error Message 00:00:06% SERIAL-3-FW_CHECKSUM_FAILED: E3 line card in slot <x>, firmware integrity check failed (section <x>, expected checksum: <x>, calculated checksum: <x>) Error Message 00:00:06% ENVM-0-SHUTDOWN: Environmental Monitor initiated shutdown due to <voltage/temperature/power supply> in slot <x> Error Message 00:00:06% SERIAL-1-ALLOCFAIL: E3 (slot <x>) line card plugin structure allocation failure
DSU Link Doesn't Work

Symptom

The link between the 6E3 line card and digitial link DSU (DL3100E) doesn't work when subrates have been configured. Pings don't go through.

Note This is an intermittent problem that occurs with the DL3100E DSU. Other supported external CSU and DSU products are not affected.

Conditions

This symptom is observed after you have reloaded a Cisco 7304, (when a 6-port E3 line card is connected to an external digital link DSU) and when the interface has the dsu bandwidth command enabled.

Workaround

Enter the shutdown command followed by the no shutdown command on the affected interface.
Router#conf t Enter configuration commands, one per line. End with CNTL/Z. Router(config)#int ser 5/0 Router(config-if)#shut Router(config-if)#no shut
*Oct 20 21:39:34.331: %LINK-5-CHANGED: Interface Serial5/0, changed state to administratively down Router(config-if)# *Oct 20 21:39:34.331: %WS_ALARM-6-INFO: ASSERT INFO Se5/0 Physical Port Administrative State Down *Oct 20 21:39:35.331: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial5/0, changed state to down *Oct 20 21:39:37.263: %LINK-3-UPDOWN: Interface Serial5/0, changed state to down *Oct 20 21:39:37.263: %WS_ALARM-6-INFO: CLEAR INFO Se5/0 Physical Port Administrative State Down *Oct 20 21:39:37.263: %WS_ALARM-6-INFO: ASSERT MAJOR Se5/0 Physical Port Link Down Router(config-if)# Router(config-if)# *Oct 20 21:39:41.895: %LINK-3-UPDOWN: Interface Serial5/0, changed state to up *Oct 20 21:39:41.895: %WS_ALARM-6-INFO: CLEAR MAJOR Se5/0 Physical Port Link Down *Oct 20 21:39:42.895: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial5/0, changed state to up Router(config-if)#end Router#

Parameter	Configuration Command	Default Value
Clock source	clock source [internal \| line]	line
Cyclic redundancy check	crc [16 \| 32]	16
DSU mode	[no] dsu mode [cisco \| digital-link \| kentrox]	cisco
DSU subrate bandwidth	[no] dsu bandwidth kbps	34010
Encapsulation	encapsulation [frame-relay \| hdlc \| ppp]	hdlc
Idle character mode	[no] idle-character [flags \| marks]	flags
Invert data	[no] invert data	no invert data
Keepalive	[no] keepalive [seconds]	keepalive 10
Loopback mode	[no] loopback [local \| network line \| network payload \| dte]	no loopback
Maximum transmission unit	[no] mtu bytes	4470 bytes
National bit	[no] national bit [0 \| 1]	0
Payload scrambling	[no] scramble	no scramble
Transmitter delay	[no] transmitter-delay # of idle characters	0-255

Purpose	Command	Example
Enable 32-bit CRC	crc size	The example enables 32-bit CRC on a serial interface: `Router(config)# interface serial 3/0Router(config-if)# crc 32`
Return to default 16-bit CRC	no crc size	The example disables 32-bit CRC on a serial interface and returns to the default 16-bit CRC: `Router(config)# interface serial 3/0Router(config-if)# no crc 32`

Command	Function	Example
show version	Displays system Cisco IOS software version, names and sources of configuration files, and boot images	`Router# show version`
show controllers	Displays all the current E3 interfaces	`Router# show controllers`
show diag slot	Displays types of line cards installed in your system and information about a specific chassis slot	`Router# show diag 2`
show interfaces type slot-number/ interface-port-number	Displays status information about a specific type of interface (for example, serial) in a Cisco 7304 router	`Router# show interfaces serial 2/0`
show protocols	Displays protocols configured for the entire system and for specific interfaces	`Router# show protocols`
show running-config	Displays the running configuration file	`Router# show running-config`
show startup-config	Displays the configuration stored in NVRAM	`Router# show startup-config`

Command	Function	Example
loopback local	Sets the interface into local loopback mode. Local loopback loops the router output data back toward the router at the framer.	`Router(config)# interface serial 2/0Router(config-if)# loopback local`
loopback network line	Sets the interface into network line loopback mode. Network line loopback loops the data back toward the network (before the framer).	`Router(config)# interface serial 2/0Router(config-if)# loopback network line`
loopback network payload	Sets the interface into network payload loopback mode. Network payload loopback loops just the payload data back toward the network at the E3 framer.	`Router(config)# interface serial 2/0Router(config-if)# loopback network payload`
loopback dte	Sets the interface into loopback data terminal equipment (DTE) mode. Loopback DTE loops the router output data back toward the router (after the LIU).	`Router(config)# interface serial 2/0Router(config-if)# loopback dte`