Guest

Cisco MWR 1900 Mobile Wireless Routers

Field Notice: FN - 62656 - Specific MWR 1900 Mobile Wireless Series Routers Unable To Read Compact Flash - ROMMON Upgrade Available


Revised April 17, 2007

January 30, 2007

NOTICE:

THIS FIELD NOTICE IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTY OF MERCHANTABILITY. YOUR USE OF THE INFORMATION ON THE FIELD NOTICE OR MATERIALS LINKED FROM THE FIELD NOTICE IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS FIELD NOTICE AT ANY TIME.


Products Affected

Products Affected

Comments

MW19XX-MEM1900-32CF-EXT

Mobile Wireless 1900 Series Routers- 32MB Compact Flash

Problem Description

The compact flash (CF) used in specific Cisco routers may contain a defect preventing access to the Compact Flash and could cause a boot failure following a power cycle or reload. During a failed state the router will be unable to pass traffic. Cisco is providing a ROM Monitor (ROMmon) update that resolves this scenario.

Background

The Compact Flash modules were installed in specific Cisco routers manufactured between May 2005 and October 2006, or shipped individually as spares over that same time span.

This issue has been linked to a Compact Flash vendor manufacturing problem. The root cause was identified and appropriate steps taken to resolve the problem. An upgrade to the router ROM Monitor (ROMmon) is available.

Flash cards that were upgraded in the field or moved to a different chassis should be checked with the validation steps below.

Problem Symptoms

The problem symptom is typically seen during a system reload or cold start. Under normal circumstances a router's Compact Flash could contain Cisco IOS software, configurations or other files necessary for system boot or operation. These files are accessed by the router during the boot sequence to reach an operating state.

In the problem state, the router is unable to access the contents of the Compact Flash. When the problem occurs, the system is prevented from accessing information stored on the Compact Flash. This type of error occurs in the controller of the Compact Flash. Data stored on the Compact Flash should be intact but may not be accessible. The router may indicate the state with a message log below. The router will be unable to read the contents of the Compact Flash that was previously operational.

The output below shows the system log or terminal monitor message when the router is unable to read the Compact Flash contents.

%Error opening slot0:/ (No device available)

The router may stop the boot sequence and remain at a ROM Monitor (ROMmon) prompt as seen below.

Readonly ROMMON initialized 
boot: cannot open "flash:" 
boot: cannot determine first executable file name on device "flash:" 
cxxxx processor with 524288 Kbytes of main memory Main memory is configured to 64 bit mode with ECC enabled 
Readonly ROMMON initialized 
rommon 1 > 

Workaround/Solution

Cisco has made an update to the router ROM Monitor (ROMmon) software that resolves the scenario described in the Problem Symptoms section of this field notice. This fix allows the contents of the Compact Flash to be read by the router during the boot sequence.

Go to the Cisco MWR1900 Platform ROMMON Software download page (registered customers only) . Download image name: MWR1900_RM2.srec.124-11r.MC

If the Compact Flash has failed, then it is recommended to replace it with MEM1900-32CF-EXT=.

How To Identify Hardware Levels

fn62656_jcdv97.jpg

Follow the steps below to validate if your product is affected by this field notice. Please note that only flash that states, "Made in USA" are affected. Additionally, there are two methods to validate if the Compact Flash is affected:

1. Confirm Product ID and serial number range in the table below.

2. Visual inspection of compact flash is recommended if the flash is not currently installed in a router or the router is powered off. Note that powering down an affected router could trigger the symptom causing the router to remain at a ROM Monitor (ROMmon) prompt.

3. IOS inspection of compact flash is recommended if the router is currently running. Visual Inspection - Locate the Manufacturing Part Number Prefix and the Manufacturing Production Code on the Compact Flash. The image below shows the code locations on the Compact Flash.

Note: If Compact Flash is no longer paired with its original router (due to upgrade or other reasons) proceed with "Step 1" below. Manufacturing Code

Locations Location A - Manufacturing Part Number Prefix

Location B - Manufacturing Production Code

fn62656_jcdvce.jpg

fn62656_jce1xf.jpg

How To Upgrade Software

Please make sure to have backup copies of all configs or data stored in the compact flash before proceeding with the upgrade.

Steps to Upgrade:

1. Locate the new ROMMON image at the Cisco MWR1900 Platform ROMMON Software download page (registered customers only) . Image name is MWR1900_RM2.srec.124-11r.MC

2. Collect the existing ROMMON information in your router before the upgrade by using show rom-monitor command under IOS or showmon under rommon prompt

3. Upgrading the ROMMON can be done in either of two ways in IOS exec mode:

3.1 Copy the file into the CF (internal or external) and then execute the upgrade rom-monitor file flash:cXXXX.image-name command.

3.2 Upgrade by executing upgrade rom-monitor file tftp://223.255.254.254/cXXXX.image-name command.

4. After the upgrade completed, the router will be reloaded automatically. If the config register is 0x0, then the route will go to rommon prompt. Otherwise the router will boot up IOS, and go to router prompt.

5. To verify the upgrade result, use either of the following commands using showmon under rommon prompt using show rom-monitor under IOS

6. You can specify the upgrade ROMMON to be the default ROMMON by usingrommon-pref upgrade under rommon prompt using upgrade rom-monitor preference upgrade under IOS

6.1 Reboot/reload the router. A showmon or show rom-monitor should indicate the router is running the new ROMMON.

6.2 Please reboot/reload/restart (cold and warm) the router a couple of times and make sure it is successful every time.

7. If the new ROMMON fails to work, then you can revert back to your readonly ROMMON by using rommon-pref readonly under rommon prompt using upgrade rom-monitor preference readonly under IOS

7.1 Reboot/reload the router. A showmon or show rom-monitor should indicate same information as in Step 2. (old ROMMON version)

Another ROMMON upgrade procedure that should work for the MWR1941 is also located at:

ROM Monitor Download Procedures for Cisco 2691, Cisco 3631, Cisco 3725, and Cisco 3745 Routers

Frequently asked Questions (FAQs)

Q1 - Will formatting the Compact Flash resolve this issue?

A1 - No, attempts to format the Compact Flash will not resolve the problem. When the problem occurs data should be intact and re-formatting after applying the solution should not be necessary.

Q2 - I've applied the solution, but the router does not boot. What do I do?

A2 - There may be a separate issue preventing the router from booting. Further troubleshooting may be necessary.

Q3 - If the router has observed the symptom described in this field notice and stops at ROMMON, can I use the same CF to boot a different router?

A3 - The same compact flash cannot be used to boot a different router. After the same flash is fixed using upgrade ROMMON it may be used in the same or different router.

Q4 - What do I do if the router is currently in ROMMON mode?

A4 - Reference the Cisco Tech Tip for instructions on booting the router using TFTP or use another compact flash.

Tech Tip: ROM Monitor Download Procedures for Cisco 2691, Cisco 3631, Cisco 3725, and Cisco 3745 Routers

Revision History

Revision

Date

Comment

1.1

17-APR-2007

Updated Workaround/Solution section to include CF replacement PID.

1.0

30-JAN-2007

Initial Public Release

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.