Cisco Catalyst 6500 Series Switches

Field Notice: Incorrectly Programmed Serial EEPROM May Cause Fan-Fail Alarm in WS-C6509-NEB-A Chassis Field Notice

June 11, 2004

Products Affected


Part Number



Serial Numbers

Random #

FOX071700K5 FOX071700KV FOX07210459 FOX0721045G FOX0721045T FOX07210460 FOX07210469 FOX0721046H FOX0721046Q FOX0721048Q FOX0721048Y FOX07210495 FOX0721049D FOX0721049L FOX0721049T FOX074600ME FOX074600MN FOX07460153 FOX0746015A FOX0746015H FOX074601HL FOX0750070D FOX0750070L FOX0750070T FOX075104KD FOX075104KL FOX080105SM FOX080105SU FOX080105T3

FOX071700K7 FOX0719019S FOX0721045A FOX0721045H FOX0721045U FOX07210461 FOX0721046A FOX0721046J FOX0721046R FOX0721048R FOX0721048Z FOX07210496 FOX0721049E FOX0721049M FOX0721049V FOX074600MF FOX074600MP FOX07460154 FOX0746015B FOX07460160 FOX074601HM FOX0750070E FOX0750070M FOX075101F1 FOX075104KE FOX075104KM FOX080105SN FOX080105SV FOX080105T4

FOX071700KJ FOX071901A8 FOX0721045B FOX0721045J FOX0721045V FOX07210462 FOX0721046C FOX0721046K FOX0721048K FOX0721048S FOX07210490 FOX07210498 FOX0721049F FOX0721049N FOX0721049W FOX074600MG FOX0746014Y FOX07460155 FOX0746015C FOX07460161 FOX07500708 FOX0750070F FOX0750070N FOX075101F2 FOX075104KF FOX075104KN FOX080105SP FOX080105SW FOX080105T5

FOX071700KK FOX071901AD FOX0721045C FOX0721045K FOX0721045W FOX07210462 FOX0721046D FOX0721046L FOX0721048L FOX0721048T FOX07210491 FOX07210499 FOX0721049G FOX0721049P FOX0721049X FOX074600MJ FOX0746014Z FOX07460156 FOX0746015D FOX074601HG FOX07500709 FOX0750070G FOX0750070P FOX075101F3 FOX075104KG FOX075104KP FOX080105SQ FOX080105SX FOX080105V8

FOX071700KL FOX071901AK FOX0721045D FOX0721045L FOX0721045X FOX07210463 FOX0721046E FOX0721046M FOX0721048M FOX0721048U FOX07210492 FOX0721049A FOX0721049H FOX0721049Q FOX0721049Y FOX074600MK FOX07460150 FOX07460157 FOX0746015E FOX074601HH FOX0750070A FOX0750070H FOX0750070Q FOX075101F4 FOX075104KH FOX075104KQ FOX080105SR FOX080105SY FOX080105VB

FOX071700KM FOX071901AL FOX0721045E FOX0721045Q FOX0721045Y FOX07210464 FOX0721046F FOX0721046N FOX0721048N FOX0721048V FOX07210493 FOX0721049B FOX0721049J FOX0721049R FOX0721049Z FOX074600ML FOX07460151 FOX07460158 FOX0746015F FOX074601HJ FOX0750070B FOX0750070J FOX0750070R FOX075104K5 FOX075104KJ FOX075104KR FOX080105SS FOX080105SZ FOX080105VC

FOX071700KS FOX07210458 FOX0721045F FOX0721045S FOX0721045Z FOX07210467 FOX0721046G FOX0721046P FOX0721048P FOX0721048X FOX07210494 FOX0721049C FOX0721049K FOX0721049S FOX072104A1 FOX074600MM FOX07460152 FOX07460159 FOX0746015G FOX074601HK FOX0750070C FOX0750070K FOX0750070S FOX075104K6 FOX075104KK FOX075104KS FOX080105ST FOX080105T2

Problem Description

When only one fan tray is present in a Catalyst WS-C6509-A chassis, the system may erroneously indicate that a fan failure has occurred, and the active Supervisor module's status LED may turn orange.


Catalyst WS-C6509-NEB-A chassis which fall within the above serial number range have a Serial EEPROM which was misconfigured during the manufacturing process. This misconfigured EEPROM causes the chassis to incorrectly set the minimum fan tray threshold to two instead of one. Therefore, when only a single fan tray is present, the system goes into an error state, and the Supervisor module's status LED turns orange.

Problem Symptoms

Catalyst WS-C6509-NEB-A chassis in the affected serial number range, which only have a single fan tray installed, will generate the following error messages under IOS:

%C6KENV-SP-4-FANTRAYFAILED: fan tray 2 failed
%SNMP-5-CHASSISALARM: Chassis Alarm Trap: tmpAlarm(OFF), minorAlarm(ON), and/or majorAlarm(OFF)

Note: No error messages are generated on systems running CatOS.

Also, in a single fan tray system, if the show environment alarm command is issued in IOS, or the show environment cooling command in CatOS, the output erroneously indicates that the system is experiencing a fan tray failure:

Cisco IOS Software:
Switch#show environment alarm
environmental alarms:
system minor alarm on fan-tray 2 fan-fail (raised 00:02:56 ago) !--- Erroneous output in italics

Cisco CatOS Software:
Console> (enable) show environment cooling

Chassis per slot cooling capacity : 76 cfm

Fan tray(s) cooling capacity :

Fan  Model               Ver Cooling  Ambient FanStatus
                             capacity temp             
---- ------------------- --- -------- ------- ---------
1    FAN-MOD-9            2   690 cfm   55C      ok
2                         -      -        -      fail
!--- Erroneous output in italics


Slot cooling requirement :

Slot CardType            Cooling
---- ------------------- -------
5    WS-SUP720-BASE       35 cfm
9    WS-X6248-RJ-45       30 cfm

The show power command in IOS, and the show system command in CatOS generate similar erroneous output:

Cisco IOS Software:
Switch#show power
system power redundancy mode = combined
system power total =     2830.80 Watts (67.40 Amps @ 42V)
system power used =      1172.64 Watts (27.92 Amps @ 42V)
system power available = 1658.16 Watts (39.48 Amps @ 42V)

                        Power-Capacity PS-Fan Output Oper
PS   Type               Watts   A @42V Status Status State
---- ------------------ ------- ------ ------ ------ -----
1    WS-CAC-3000W       2830.80 67.40  OK     OK     on
2    none

                        Pwr-Allocated  Oper
Fan  Type               Watts   A @42V State
---- ------------------ ------- ------ -----
1    FAN-MOD-9           241.50  5.75  OK
2                        241.50  5.75  failed
!--- Erroneous output in italics

[Remaining Output Removed...]

Cisco CatOS Software:
Console> (enable) show system
PS1-Status PS2-Status 
---------- ---------- 
ok         ok         

Fan-Status Temp-Alarm Sys-Status Uptime d,h:m:s Logout
---------- ---------- ---------- -------------- ---------
ok         off        faulty    0,00:59:28     none !--- Erroneous output in italics

[Remaining Output Removed...]


This procedure should be used to update an EEPROM on the backplane of the WS-C6509-NEB-A chassis to correct a misprogrammed FRU Minor value. The procedure includes downloading an EEPROM update image, copying that image to system flash, booting the system to ROMMON, executing the EEPROM update image, and then restoring the systems' previous IOS or CatOS image. Once this process has been successfully completed, they system should no longer experience a fan tray failure alarm when only a single fan tray is installed.

Step 1: Select and download the appropriate image for your system:

Supervisor 1�c�c�c�csprom-sup1-6509neba-swupdate-1.hZ (registered customers only)

Supervisor 2�c�c�c�csprom-sup2-6509neba-swupdate-1.hZ (registered customers only)

Supervisor 720�c�c�csprom-sup720-6509neba-swupdate-1.hZ (registered customers only)

Note: This image must only be run from the active Supervisor while it is in ROMMON. If a standby Supervisor is present, it will need to be powered down for the duration of the upgrade process.

Step 2: Copy the image onto the system flash or a removable flash device installed in the system. This process is the same as that used to copy any image onto a Cisco flash device. For more information on this procedure, please refer to either the Cisco IOS Software document entitled Loading and Maintaining System Images or the Cisco CatOS document entitled Upgrading Software Images on Catalyst 6000/6500 Series Switches.

Step 3a: Record the name and location of the current software image running on the system. This can be accomplished by issuing one of the following commands, and witting down the output indicated in italics.

Cisco CatOS:

Console> (enable) show version | include System Boot Image File
System Boot Image File is'[device]:[System-image-name]'
!--- Important output in italics

Cisco IOS:

Router# show version | include System image
        System image file is "[device]:[System-image-name]"
!--- Important output in italics

Step 3b: Record the current configuration register value by issuing one of the following commands, and witting down the output indicated in italics.

Cisco CatOS:

Console> (enable) show version | include Configuration register
        System Configuration register is 0x2
!--- Important output in italics

Cisco IOS:

Router# show version | include Configuration register
        Configuration register is 0x2102
!--- Important output in italics

Step 4: Set the configuration register so that upon reload, the system will boot into ROMMON.

Cisco CatOS:

Console> (enable) set boot config-register 0x0

Cisco IOS:

Router# configure terminal
        Router#(config) config-register 0x0   
        Router#(config) exit

Step 5: At this point the upgrade image should be loaded on a valid flash device in the system, and the system image name or location and configuration register should be recorded or logged in a safe place. Once each of these three tasks is complete, it is safe to reload the system so that it can boot into ROMMON.

Cisco CatOS:

Console> (enable) reset

Cisco IOS:

Router# reload

Note: If at any point during the reload process you are prompted to save your configuration file, do so, or you will lose any configuration changes made since the last save.

Step 6: Once the system has been reloaded, if you do not see a ROMMON prompt, press the Enter key a couple of times. Once the ROMMON prompt appears you will need to execute the EEPROM update image in order to correct the chassis EEPROM. Issue the following command to begin the EEPROM update:


rommon 1 >  boot [device]:[EEPROM-update-image-name]

After the EEPROM update image is done running, it will display a status dialogue, indicating if the EEPROM update was a success or a failure. If the upgrade was unsuccessful, follow the instructions outlined in the error message, and execute the EEPROM update image once more.

Step 7: If the update was successful, then the previously running system image must now be reloaded, using the image identified in Step 3a.


rommon 1 >  boot [device]:[system-image-name]

Step 8: Once the system is back online change the config-register value back to its original value, as noted in Step 3b.

Cisco CatOS:

Console> (enable) set boot config-register [value from Step 3b]

Cisco IOS:

Router# config terminal 
        Router#(config) config-register [value from Step 3b]
        Router#(config) exit 

Step 9: Power up the standby Supervisor, if present.


Below is sample output from the successful execution of the EEPROM update image:

rommon 1 > boot disk0:sprom-sup720-6509neba-swupdate-1.hZ
Uncompressing file: ######### [Output Removed...]
SR71K Interface (600 MHz)
System Power On Diagnostics
DRAM Size ....................64 MB
NVRAM Size ...................512KB
Level2 Cache .................Present ( 512 KB)
Boot image: slot0:sprom-sup720-6509neba-swupdate-1.hZ
Updating chassis SPROM ....
Chassis SPROM has been updated.
eobc_init_if: unit = 1 okay
System Bootstrap, Version 7.7(1)
Copyright (c) 1994-2003 by cisco Systems, Inc.
Cat6k-Sup720/SP processor with 524288 Kbytes of main memory
rommon 1 >


To follow the bug ID link below and see detailed bug information, you must be a registered user and you must be logged in.



CSCea58341 (registered customers only)

WS-C6509-NEB-A: fan-fail alarm when only 1 fan present

How To Identify Hardware Levels

In order to determine whether or not a given WS-C6509-NEB-A chassis is affected, one of the following commands must be executed on the system, and its output must be analyzed:

  • IOS: show idprom backplane

  • CatOS: show sprom chassis

Affected chassis will have a serial number which falls within the range defined at the top of this Field Notice. The chassis will also have a Manufacturing Assembly Number (IOS) or a Part Number (CatOS) of 73-7360-03. Lastly, in IOS, the FRU will be Cisco 7600 9-slot backplane, or, in CatOS, the FRU Minor Type will be 0x9004. Below are output examples of both the IOS and CatOS commands.

Cisco IOS Software:
Switch#show idprom backplane
IDPROM for backplane #0
  (FRU is 'Cisco 7600 9-slot backplane')
!--- Important information in italics

  OEM String = 'Cisco Systems'
  Product Number = 'WS-C6509-NEB-A'
  Serial Number = 'ABC012345XY'
  Manufacturing Assembly Number = '73-7360-03'
!--- Important information in italics

  Manufacturing Assembly Revision = '01'
  Hardware Revision = 0.101
  Current supplied (+) or consumed (-) =  -

Cisco CatOS Software:
 Console> (enable) show sprom chassis
 Chassis eeprom #1:
 Common block:
  Block Signature : 0xabab
  Block Version   : 2
  Block Length    : 156
  Block Checksum  : 0x1328
  EEPROM Size     : 512
  Block Count     : 2
  FRU Major Type  : 0x6001
  FRU Minor Type  : 0x9004
!--- Important information in italics

  OEM String      : Cisco Systems
  Product Number  : WS-C6509-NEB-A
  Serial Number   : ABC012345XY
  Part Number     : 73-7360-03
!--- Important information in italics

  Part Revision   : B1
  Mfg Deviation   :
  H/W Version     : 1.0
  Mfg Bits        : 0
  Engineer Use    : 0
  snmpOID         :
  Power Consump   : 0
  RMA Code        : 0-0-0-0
  CLEI            : IPM5800CRA

[Remaining Output Removed...]

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:

Receive Email Notification For New Field Notices

Product Alert Tool - Set up a profile to receive email updates about reliability, safety, network security, and end-of-sale issues for the Cisco products you specify.