Recovering a Catalyst 5000 RSM from a Corrupted or Missing Image, Boot, or ROMmon Mode

Document ID: 21382

Introduction
Before You Begin
      Conventions
      Prerequisites
      Components Used
Normal Operation
Recovering from Boot Mode
      Step-by-Step Instructions
Recovering from ROMmon Mode
      Step-by-Step Instructions
Final Check After Returning to Router> Prompt
Related Information

Introduction

This document explains how to recover a Catalyst 5000 Route Switch Module (RSM) from a missing or corrupted system image. A Layer 3 (L3) module image can sometimes be corrupted during a TFTP download, or deleted and squeezed (but not replaced) manually by the user. In other cases, the Flash device itself can become corrupted and require reformatting. The RSM provides a number of ways to recover if any of these events occur.

When the RSM boots up or resets, there are three possibilities, as follows:

The RSM starts up normally and displays the Router> prompt.
The RSM has a missing or corrupted system image, but is able to run from a boot helper or RXboot image. It displays the Router(boot)> prompt. This is a scaled down version of the system image which allows you to perform the copy tftp procedure to recover.
The RSM cannot find or has a corrupt boot image as well, and therefore it ends up in ROM monitor (ROMmon) mode. It displays the rommon> prompt. In ROMmon mode, the RSM must be able to locate a valid boot or system image. There is no option for Xmodem or Ymodem that allows you to copy an image through the console port.

In addition to the 8 MB internal Flash Single In-Line Memory Module (SIMM), the RSM has two Personal Computer Memory Card International Association (PCMCIA) card slots for up to 20 MB each: slot0 (bottom) and slot1 (top). If the system image or the boot image fails, theses devices provide a backup. The Flash devices are recognized in ROMmon, and the images stored there can be used to recover. For this reason, the RSM ships with a 16 MB PCMCIA card in slot0, which is the default Flash device.

Before You Begin

Conventions

For more information on document conventions, see the Cisco Technical Tips Conventions.

Prerequisites

There are no specific prerequisites for this document.

Components Used

The information in this document is based on the software and hardware versions below.

Catalyst 5000 series switch
RSM running Cisco IOS® Software Release 12.2(10b)

The information presented in this document was created from devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If you are working in a live network, ensure that you understand the potential impact of any command before using it.

Normal Operation

When the RSM is operating normally it is at the Router> or Router# prompt. You can issue the dir bootflash:, dir slot0:, or dir slot1: commands to view the contents of the RSM Flash devices. Issue the verify command to see if the image has a valid checksum. The following provides an example:

Router#dir bootflash:
Directory of bootflash:/

 1  -rw-     6761060   Jan 01 2000 00:49:41  c5rsm-boot-mz.122-10b.bin

7602176 bytes total (716268 bytes free)

Router#verify bootflash:
Verify filename []?
?File name not specified
RSM_mod3#verify bootflash:c5rsm-boot-mz.122-10b.bin
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCC
Verified bootflash:c5rsm-boot-mz.122-10b.bin

Since the RSM recognizes all Flash devices in both Boot mode and ROMmon mode, you can issue these same commands to view and verify Flash contents in Boot mode or ROMmon mode, as demonstrated in the sections Recovering from Boot Mode and Recovering from ROMmon Mode, below.

Notice in the Normal Operation example above, that there is only a single boot image in bootflash. This is the boot helper image. You can have either one or two boot images (depending on the size of the boot image), or just one system image, in bootflash without exceeding the 8 MB limit. Flash cards in slot0 and slot1, on the other hand, can be up to 20 MB each. You can manage the bootflash and Flash cards as you wish, but consider distributing the images between these devices for more redundancy in the case of failure.

For this document, one boot image is in bootflash and one system image is in slot0. Whether the image is missing, deleted, or corrupt, the RSM most likely ends up in one of two modes: Boot mode or ROMmon mode.

Recovering from Boot Mode

The RSM can end up in Boot mode as the result of a switch reset or RSM module reload after the image is corrupted or deleted, possibly after the config-register is changed.

You notice these primary symptoms from the switch side if the L3 blade is in Boot mode:

Routing failures occur because Boot mode cannot route between VLAN interfaces. It is a limited-feature set image designed to facilitate the copy tftp procedure.
If you session between the switch and the RSM, or if you are connected to the console port of the RSM, you see the following prompt:
```
Router(boot)>
```

Step-by-Step Instructions

Perform the steps below, in the order given, to facilitate a successful image recovery from Boot mode.

Step 1

You have two choices in this first step.
- You may choose to issue the session mod command from the switch side, as in the following example:
```
Console> (enable) session 5 
Trying Router-5... 
Connected to Router-5. 
Escape character is '^]'. 
Router(boot)>
```
  If you can still session in this manner, and if you find yourself at the Router(boot)> prompt, proceed directly to Step 2.
- If you cannot session or you already have a console connection to the RSM, on a standard Windows operating system platform configure a HyperTerminal connection directly to COM1 with the following settings:
  - 9600 bps
  - Eight data bits
  - No parity
  - One stop bit
  - Flow control none
Use a rolled male RJ-45 cable to connect from COM1 on the PC to the console port on the Catalyst 5000 RSM module. Use a DB-9 connector on the PC and a DB-25 adapter on the console port (Cisco part number CAB-25AS-MMOD= or equivalent. For more information on Cisco part number CAB-25AS-MMOD=, refer to the document Serial Cables, and scroll down to CAB-25AS-MMOD=). Cisco also makes a dedicated DB25-to-DB25 cable (part number CAB-RSM2CON), if you prefer it.
Use the HyperTerminal connect window to connect to the RSM. Press Enter to get to the Router(boot)> prompt.

Step 2

The main system image has a problem, but the RSM has successfully started up from the boot helper image.

At the enable prompt, issue the show slot0: command. Slot0: is where the system image is located for this document.

Issue the verify command to verify the image.

The following provides an example of these steps:

Router(boot)#show slot0:
-#- ED ----type---- --crc--- -seek-- nlen -length- -----date/time------ name
1   .. image        8A7B9039  C556DC   24 12801628 Jan 01 2000 00:29:37 c5rsm-jsv-mz.122-10b.bin
3582244 bytes available (12801756 bytes used)

Router(boot)#verify slot0:c5rsm-jsv-mz.122-10b.bin
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCC
Verified slot0:c5rsm-jsv-mz.122-10b.bin

Step 3

Look for a missing or deleted image. If you issue the show slot0: command, it shows .D for deleted, as in the following example:

Router(boot)#show slot0:
-#- ED ----type---- --crc--- -seek-- nlen -length- -----date/time------ name
1   .D image        8A7B9039  C556DC   24 12801628 Jan 01 2000 00:29:37 c5rsm-jsv-mz.122-10b.bin

Try to restore the image with the undelete command, as in the following example:
```
Router(boot)#undelete ? 
  <1-1024>  File index number 
 
Router(boot)#undelete 1 slot0:
```
If the undelete command is successful, you see the following output displayed:
```
Router(boot)#show slot0:
-#- ED ----type---- --crc--- -seek-- nlen -length- -----date/time------ name
1   .. image        8A7B9039  C556DC   24 12801628 Jan 01 2000 00:29:37 c5rsm-jsv-mz.122-10b.bin
```
If all images are missing or removed, you see the following (with a 16MB PCMCIA Flash card):
```
Router(boot)#dir slot0:
Directory of slot0:/

No files in directory

16384000 bytes total (16384000 bytes free)
```
If the image is missing altogether or Step 3 proves unsuccessful, (any outcome other than what is shown in Step 3 is displayed), then proceed directly to Step 4. Otherwise, continue by following the directions below.
Be sure a boot variable is configured, and verify that the config-register is set correctly, as shown in the following example:
```
Router(boot)#show bootvar
BOOT variable = slot0:c5rsm-jsv-mz.122-10b.bin,1;
CONFIG_FILE variable does not exist
BOOTLDR variable = bootflash:c5rsm-boot-mz.122-10b.bin
Configuration register is 0x2102
```
The BOOT variable determines the system image from which the RSM boots, just as the BOOTLDR variable determines the boot image to use. These commands are useful when dealing with multiple images on a Flash device. For now, be sure that the config register is set to 0x2102, which directs the module to boot from Flash. If it is not, the following is an example of how to configure it:
```
Router(boot)#configure t 
Enter configuration commands, one per line.  End with CNTL/Z. 
Router(boot)(config)#config-register 0x2102
```
Issue the reload command.

Do not save your configuration. Saving your configuration overwrites the previous configuration in Non-Volatile RAM (NVRAM), causing you to lose your original configuration after issuing the reload command.
```
Router(boot)#reload 
01:46:07: %SYS-5-CONFIG_I: Configured from console by console 
System configuration has been modified. Save? [yes/no]:n

!--- Type n for "no" here.
```

Step 4

If the RSM falls back to the Router(boot)> prompt, you should follow these steps to permanently erase this system image:

Delete the system image.

Issue the squeeze command.

The following provides an example of these steps:

Router#delete slot0:c5rsm-jsv-mz.122-10b.bin
Delete filename [c5rsm-jsv-mz.122-10b.bin]?
Delete slot0:c5rsm-jsv-mz.122-10b.bin? [confirm]

Router#squeeze slot0:
All deleted files will be removed. Continue? [confirm]
Squeeze operation may take a while. Continue? [confirm]
Squeezing...Erasing squeeze buffer 

!--- Output suppressed.

Squeeze of slot0 complete

Step 5

If, despite the previous steps, the RSM remains in Router(boot)>, you need to perform the copy tftp procedure to place another image into Flash. An interface VLAN needs to be created.

Boot mode has limited routing capabilities, so if the tftp server is not on the same local subnet as the VLAN interface, a default gateway is required.

Issue the ip default-gateway command to enter a gateway router IP address, if necessary.

In the example below, the TFTP server is directly connected to the switch, so no default gateway is required.

Router(boot)(config)#interface vlan 1
00:08:01: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, 
changed state to down 
Router(boot)(config-if)#ip address 10.10.10.1 255.255.255.0
Router(boot)(config-if)#no shut
00:08:44: %LINK-3-UPDOWN: Interface Vlan1, changed state to up 
00:08:45: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, 
changed state to up 

Router(boot)#show run 

!--- Output suppressed.

interface Vlan1 
 ip address 10.10.10.1 255.255.255.0 
 no ip directed-broadcast 
 no ip route-cache 
!

Step 6

Using a straight-through cable, connect the PC Network Interface Card (NIC) to a Catalyst 5000 switching module.
Be sure the port to which it connects is in the same VLAN as the VLAN interface on the RSM (VLAN1 in this case).

Verify that you can ping the TFTP server, as follows:

Router(boot)#ping 10.10.10.2

Type escape sequence to abort. 
Sending 5, 100-byte ICMP Echos to 10.10.10.2, timeout is 2 seconds: 
!!!!! 
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/201/1000 ms

Step 7

Download an RSM intelligent module software image to your TFTP server hard drive. For more information on downloading an image, refer to Tools and Utilities.

Begin the copy tftp procedure, as follows:

Router(boot)# copy tftp slot0:
Address or name of remote host []? 10.10.10.2 
Source filename []? c5rsm-jsv-mz.122-10b.bin
Destination filename [c5rsm-jsv-mz.122-10b.bin]? 
Accessing tftp://10.10.10.2/c5rsm-jsv-mz.122-10b.bin... 
Loading c5rsm-jsv-mz.122-10b.bin .from 10.10.10.2 (via Vlan1): !!!!!!!!!!! 
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
!!! 
[OK - 12801628/25603072 bytes]
  
12801628 bytes copied in 852.720 secs (15025 bytes/sec)
Router(boot)# 
Router(boot)#dir slot0: 
Directory of slot0:/ 

1 -rw- 12801628 Jan 01 2000 00:29:37 c5rsm-jsv-mz.122-10b.bin

16384000 bytes total (3582244 bytes free)
 
Router(boot)#verify slot0:c5rsm-jsv-mz.122-10b.bin
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCC
Verified slot0:c5rsm-jsv-mz.122-10b.bin

Router(boot)#show bootvar
BOOT variable = slot0:c5rsm-jsv-mz.122-10b.bin,1;
CONFIG_FILE variable does not exist
BOOTLDR variable does not exist 
Configuration register is 0x2102

Verify the image, and be sure that the config register is set to 0x2102, as explained in Step 3.

Note: If you experience errors copying the image file, you may need to issue the formatdevice command to reformat a corrupt device. After the device is formatted, you can continue with the image copy procedure.

Step 8

Issue the reload command for the RSM.

Do not save your configuration when in Router(boot)>.

Router(boot)#reload
 
System configuration has been modified. Save? [yes/no]: n 
Proceed with reload? [confirm] 

00:17:15: %SYS-5-RELOAD: Reload requested 
System Bootstrap, Version 11.2(17523) [mohsen 102], INTERIM SOFTWARE 
Copyright (c) 1994-1997 by Cisco Systems, Inc. 

SLOT 7 C5RSP is system master 
C5RSP processor with 32768 Kbytes of main memory 

CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 
Self decompressing the image : ################################################ 

######################################################################## 
######################################## [OK] 
Self decompressing the image :
################################################# 
######################################################################### 
######################################################################### 
######################################################################### 
# [OK] 


!--- Output suppressed.

Cisco Internetwork Operating System Software
IOS (tm) C5RSM Software (C5RSM-JSV-M), Version 12.2(10b), RELEASE SOFTWARE (fc1)


!--- Output suppressed.


cisco RSP2 (R4700) processor with 32768K/2072K bytes of memory. 
16384K bytes of Flash PCMCIA card at slot 0 (Sector size 128K). 
8192K bytes of Flash PCMCIA card at slot 1 (Sector size 128K). 
8192K bytes of Flash internal SIMM (Sector size 256K). 

Press RETURN to get started! 

Router>

Perform a final check of the config-register settings and boot system statements. For more information, refer to the Final Check After Returning to Router> Prompt section of this document.
Save your configuration.

Recovering from ROMmon Mode

There are some major differences between the kind of recovery you can accomplish in Boot mode and a recovery in ROMmon mode.

If the switch is in ROMmon mode, you notice the following:

The green status LED on the RSM turns amber.

You can no longer issue the session command to shift from the switch to the RSM, as follows:

Console> (enable) session 5 
Trying Router-5... 
session: Unable to tunnel to Router-5 (57)

You need to connect to the RSM console port. The rommon1> prompt appears.

If the RSM enters ROMmon mode, it may be that the config-register or boot variable was set incorrectly, or that a boot statement is pointing to an image that has been deleted or corrupted. In some cases, a bootable image may still exists.

Issue the dir bootflash:, dir slot0:, or dir slot1: command to determine if any images are present, as follows:
```
rommon 1 >  dir slot0:
File size                   Checksum      File name
12801628 bytes (0xc3565c)   0x8a7b9039    c5rsm-jsv-mz.122-10b.bin
```
In this case, there is an image left on slot0.
Depending on the type of image that is still present, there are two possibilities for recovering from ROMmon, as follows:
- Boot from the system image.
- Boot from the boot image. (The boot image has the word "boot" in the image name, for example, c5rsm-boot-mz.122-10b.bin.)

Step-by-Step Instructions

Step 1

Boot the system image. The system image takes you directly to the previously saved configuration and restores connectivity to the network, so always try this image first.

To boot the system image, issue the command boot device:image name . The system image for this example is on slot0.

rommon 2 > boot slot0:c5rsm-jsv-mz.122-10b.bin
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCC
Self decompressing the image : #############################################################
################################################## [OK]

!--- Output suppressed.


16384K bytes of Flash PCMCIA card at slot 0 (Sector size 128K).
8192K bytes of Flash internal SIMM (Sector size 256K).


Press RETURN to get started!

Router>

Step 2

If you do not have a system image, you can still recover using the boot image and return to the Router(boot)> prompt.

Perform the copy tftp procedure, outlined in Steps 7-8 of Recovering from Boot Mode, to reach the Router> prompt.

Store this image in bootflash. Bootflash is the a good place to store it, as the boot image is about half the size of the system image.

rommon 9 > boot bootflash:c5rsm-boot-mz.122-10b.bin
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 
CCCCCCCCCCCCCC 
Self decompressing the image : ####################### 
############################################## 
####################################### 


!--- Output suppressed.

Press RETURN to get started! 
 
Router(boot)>

The RSM also enters the ROMmon mode if there are no valid images on both the bootflash and the Flash devices. Since there is no Xmodem or Ymodem disaster recovery available on the RSM, you have the following options if all boot images and system images on all Flash devices—bootflash, slot0 and slot1—are missing or corrupt:

Use a PCMCIA card from another RSM, if available.
Use a compatible PCMCIA card with the same filesystem from another Cisco device. The RSM uses Filesystem Class "A". For a list of Cisco devices that use the same PCMCIA formatting, refer to PCMCIA Filesystem Compatibility Matrix and Filesystem Information.

Note: PCMCIA Flash memory cards must be formatted either on the RSM or on one of the devices cited in PCMCIA Filesystem Compatibility Matrix and Filesystem Information, and they must be running the same or later software version as the RSM. Flash memory cards previously formatted on a Route Processor (RP)-based Cisco 7000 series router cannot be used on the RSM.
If all of these options fail, open a case with Cisco Technical Assistance Center (TAC). Registered users may open a case with Cisco TAC. If you are not a registered user, go to User Registration.

Final Check After Returning to Router> Prompt

Be sure the correct image is installed by issuing the dir bootflash:, dir slot0:, or dir slot1: command. Compare the image length (size in bytes) to the same image on the Cisco Downloads.

If you wish, verify the cheksum of the file by issuing the verify command.

The following provides an example of these steps:

Router#dir bootflash:
Directory of bootflash:/

 1  -rw-     6761060   Jan 01 2000 00:49:41  c5rsm-boot-mz.122-10b.bin

7602176 bytes total (716268 bytes free)

Router#verify bootflash:
Verify filename []?
?File name not specified
RSM_mod3#verify bootflash:c5rsm-boot-mz.122-10b.bin
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCCCC
Verified bootflash:c5rsm-boot-mz.122-10b.bin

Configure a boot variable and verify that the config-register is set correctly. The boot system command determines the image from which the RSM module boots.

Next, set the config-register to boot from the default Flash device (slot0: for the RSM) by issuing the config-register 0x2102 command.

Save the configuration to memory by issuing the write memory command, and verify the boot variable settings by issuing the show bootvar command.

The following provides an example of these steps:

Router#configure t
Enter configuration commands, one per line.  End with CNTL/Z. 
Router(config)#boot system slot0:c5rsm-jsv-mz.122-10b.bin
Router(config)#config-register 0x2102
Router(config)#exit
 
Router#write memory 
Building configuration... 
[OK] 

Router#show bootvar
BOOT variable = c5rsm-jsv-mz.122-10b.bin,1;
CONFIG_FILE variable does not exist
BOOTLDR variable = 
Configuration register is 0x2102

Related Information

Updated: Nov 16, 2007

Document ID: 21382

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