Cisco 12000 Series Routers

Field Notice: Cisco 12000 Series ROM Monitor Cache Error Exception

September 3, 1999

Products Affected




The Gigabit Route Processor (GRP) is used in Cisco 12000 series Gigabit Switch Routers (GSRs) and serves as the main system processor for the GSRs.

Problem Description

An error in the ROM Monitor (ROMMON) code bundled with the 12000 series Cisco IOS images may prevent the router from reloading correctly after the ROMMON is upgraded. This ROMMON error is tracked with Cisco software defect CSCdm89160.

The problem can only occur if the Cisco 12000 series router is operating with one of the affected Cisco IOS maintenances and the ROMMON is manually upgraded. If these conditions are met, a Cache Error Exception error will display causing the Cisco 12000 series router to fail the boot process.

Cisco will defer the affected images.


CSCdm70130 introduced the ROMMON software defect. See the Cisco IOS Versions Affected section for a listing of Cisco IOS trains, maintenances, and images affected.

Problem Symptoms

After upgrade rom slot rp-slot# or upgrade all, the Cisco 12000 series router will experience a Cache Error Exception error due to uninitialized memory. If the GRP is in autoboot mode, it appears to keep crashing with this Cache Error Exception error.

*** Cache Error Exception ***
Cache Err Reg = 0xa4240560
data reference, primary cache, data field error , error on SysAD Bus
PC = 0xbfc00e04, Cause = 0x8000, Status Reg = 0x30408404
Tiger Masked Interrupt Register = 0x000000ff
Tiger Interrupt Value Register = 0x0000000c

This error will prevent the router from booting correctly. If this error occurs, use the recovery procedure documented in the Workaround/Solution section.


To Avoid the "Cache Error Exception" Error

  • Do not manually upgrade the ROMMON.

  • Downgrade to an older Cisco IOS 12000 series image until a solution is available.

Routers configured with the service upgrade all command will not be affected by this software defect since this command does not upgrade the GRP ROMMON.


If a Cache Error Exception error occurs after meeting the conditions described in the Problem Description section:

  • Contact Cisco Technical Support (see the For More Information section below) and request the recovery procedure documented in CSCdm89160.


  • Upgrade to Cisco IOS Software Release 11.2(18)GS2 or 12.0(6)S.

Cisco IOS Solution

Cisco IOS Trains

Cisco IOS Maintenances

Cisco IOS Images

Date Available


11.2(18)GS2 or later 11.2GS images

all gsr images (gsr-*-mz)

Forecast to CCO: September 6, 1999


12.0(6)S or later 12.0S images

all gsr images (gsr-*-mz)

Forecast to CCO: September 7, 1999


This defect has Cisco bug ID CSCdm89160. If you are a registered CCO user and you have logged in, you can view the bug details.




GSR: cache error exception after upgrading to 11.2(17)GS1 rommon

Cisco IOS Versions Affected

The affected images will be removed from and will not be shipped with new products.

Cisco IOS Trains Affected

Cisco IOS Maintenances Affected

Cisco IOS Images Affected




all gsr images (gsr-*-mz)





all gsr images (gsr-*-mz)

How To Upgrade Software

For more information, refer to the IOS Downloads (registered customers only) page.

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:

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