Troubleshooting

The Cisco ASR 901 router undergoes extensive testing before it leaves the factory. If you encounter problems, use the information in this appendix to help isolate problems or to eliminate the router as the source of the problem.

This appendix contains the following sections:

If you cannot locate the source of the problem, contact a customer service representative for information on how to proceed. For technical support information, see the Cisco Information Packet publication that shipped with your router. Before you call, have the following information ready:

  • Chassis type and serial number
  • Maintenance agreement or warranty information
  • Type of software and version number
  • Date you received the new chassis
  • Brief description of the problem
  • Brief explanation of the steps you took to isolate the problem

Note Ensure you provide the customer service representative with any upgrade or maintenance information that was performed on the Cisco ASR 901 router after your initial installation (see Appendix C, “Site Log” for Site Log information.)

Problem Solving

To solve a problem, isolate the problem to a specific subsystem by comparing the current router activity to the expected router activity.

The LEDs on the front panel of the router enable you to determine router performance and operation. For a description of these LEDs, see “Reading the LEDs” section.

When solving a problem, check the following router subsystems:

  • Power and cooling systems—External power source, power cable, router power supply and circuit breaker, and router fans. Also check for inadequate ventilation or air circulation.
  • Modules—Checking the LEDs on the modules can help you to identify a failure.
  • Cables—Ensure that the external cables connecting the router to the network are all secure.

Troubleshooting the Power and Cooling Systems

See Table A-1 for information to help you isolate the problem.

 

Table A-1 Troubleshooting the Power and Cooling Systems
Symptom
Possible Cause
Corrective Action

The power (labeled PWR) LED on the front panel is not on.

The power source is not connected properly.

Note When the Cisco ASR 901 1G router (DC unit) is powered ON, it takes about 30 seconds for the system LED to turn ON.

Check the DC input.

Check the DC source.

The router shut down after being on for only a short time.

The cause is environmental.

Check for an environmentally induced shutdown. (See “Environmental Reporting Features” section).

The fans do not work; the router overheats and shuts down.

Check the fans.

The chassis intake and exhaust vents are obstructed.

Check the chassis intake and exhaust vents for obstructions. Clear any obstructions.

Installation does not meet environmental site requirements.

Check the environmental site requirements in the “System Specifications” section .

The router partially boots, but the LEDs do not light.

There is a possible power supply failure.

Check the power LED on the front panel of the router. If the LED is on, the power supply is functional. If the LED is off, refer to the Cisco Information Packet for warranty information or contact customer service.

Environmental Reporting Features

The Cisco ASR 901 router has a temperature sensor to detect over temperature conditions inside the chassis. The over temperature detection triggers an alert at 70°C. This condition is reported to the processor as an interrupt, where software takes action to generate the appropriate alarms. If the router reaches a temperature of 85°C, the power supply will cycle to prevent the router from exceeding that temperature while being powered up state. See Table A-2 for help in interpreting environmental reporting features.

 

Table A-2 Interpreting Environmental Reporting Features
Symptom
Possible Cause
Corrective Action

The router operates at an abnormally high temperature. The following message appears on the console screen:

%SYS-1-OVERTEMP: System detected OVERTEMPERATURE condition. Please resolve cooling problem immediately!

There is a fan failure.

There is an air conditioner failure in the room.

The air flow to cooling vents is blocked.

Take corrective steps. For information about environmental operating conditions, see the System Specifications).

Troubleshooting Cables, and Connections

Network problems can be caused by a cable or cable connection, or external device such as a modem, transceiver, hub, wall jack, WAN interface, or terminal. See Table A-3 for information to help you isolate the problem.

 

Table A-3 Troubleshooting Cables, and Connections
Symptom
Possible Cause
Corrective Action

The router is experiencing network problems.

The router does not boot properly.

The router constantly or intermittently reboots.

Check the router chassis or software. For warranty information, refer to the Cisco Information Packet publication that shipped with your router or contact customer service.

 

The router boots, but the console screen is frozen.

Verify that the parameters for your terminal are set as follows:

(a) The terminal should have the same data rate as the router (9600 bps is the default).

(b) 8 data bits.

(c) No parity generated or checked.

(d) 2 stop bits.

 

 

The router powers on and boots only when a particular cable is disconnected.

There may be a problem with the module or cable. For warranty information, refer to the Cisco Information Packet publication that shipped with your order or contact customer service.

 

Reading the LEDs

The following sections describe the LEDs on the Cisco ASR 901 router.

Chassis LEDs

Table A-4 summarizes the LEDs on the chassis of the Cisco ASR 901 router. These LEDs are common to all versions of the Cisco ASR 901 router.

 

Table A-4 LED Summary
Copper GE ports (from GE/FE Quad PHY) contain will have Two LEDS each

RJ-45 Link

L

Solid Green

PHY

Link with no activity

FLASH Green

Link with activity

Off

No link

RJ-45 Speed

S

Green

PHY

Speed 1000

Off

off
T1/E1 ports contain Two LEDs each

Alarm

AL

Off

WP2

Not configured

Yellow

Alarm Condition

Active

C

Off

WP2

Out of Service / Not configured

Green

Carrier Condition (all-ok)
Copper GE (from Quad combo PHY) ports contain Two LEDS each.

RJ-45 Link

L

Solid Green

PHY

Link with no activity

FLASH Green

Link with activity

Off

No link

RJ-45 Speed

S

Green

PHY

Speed 1000

Off

off
System LED

System

Off

HP

No power or unit not boot-up

Alternating Green/Off

POST in progress

Solid Green

System Healthy (normal operation)

Solid Red

System Faulty
SFP LED

SFP Link-Active

L-A

Orange

HP

Link and Active Indicator

Off

Not Enabled

T1/E1 Interface LEDs

Table A-5 summarizes the LEDs on the T1/E1 interface (available only for A901-12C-FT-D and A901-4C-FT-D).

 

Table A-5 T1/E1 Port LEDs
LED
Color/State
Description (two LEDs for each T1/E1 port)

Active (labeled C, left LED)

Green

Carrier condition—operating without problem

Yellow

Loop condition

Off

Out of service or not configured

Alarm (labeled AL, right LED)

Yellow

Alarm condition

Off

No alarm

SFP Ethernet Interface LEDs

Table A-6 gives information about the LEDs on the SFP interface.

 

Table A-6 SFP LEDs
LED
Color/State
Description

SFP Link/Active (labeled LINK ACT)

Orange

Link and active indicator

Off

Link not enabled

RJ-45 Ethernet Interface LEDs

Table A-7 summarizes the LEDs on the RJ-45 Ethernet interface.

 

Table A-7 100/1000 Ethernet Port LEDs
LED
Color/State
Description (two LEDs for each 100/1000 Ethernet port)

100/1000 RJ-45 link (labeled L, left LED)

Solid Green

Link with no activity

Flash Green

Link with activity

Off

No link detected

100/1000 RJ-45 speed (labeled S, right LED)

Green

Speed 1000

Yellow

Speed 100

Off

Off