Cisco Catalyst Switch has been in Rommon mode unable to start iOS problem resolution

Found that Cisco Catalyst Switch reboot is always in rommom mode, the system reboots when the Confreg command chooses the startup mode of 1 (starting from the first file) and cannot enter the normal interface.

Enter to boot:

0 = Disable Autoboot

1 = the internal flash device

2 = commands specified in ' BOOT ' environment variable

[2]: 1

The analysis suggested that the iOS file might be corrupted or purged, or that the correct iOS could not be started. If the iOS is damaged or cleared, you need to import a new iOS to Flash, from the Internet, there are two methods, one is TFTP upload, one is Xmodem way upload, xmodem upload slower, need a few hours. TFTP upload is to set the system variable first, then execute the tftpdnld command, but found that the switch does not have TFTPDMLD command. It was later found that the XMODEM command was not supported. So only consider pulling down the flash card, put it into another switch to import iOS. But let's see if there's any iOS in Flash.

Check for iOS in Flash. Enter the command in rommom mode: Dir bootflash: Display the files on Flash, the first file is not the correct iOS file, the second is the correct iOS file. It's a lot easier.

Set the startup mode to 2 with the Confreg command, and then manually boot from the correct iOS:

Rommon 2 >boot Bootflash:cat4000-is-mz.121-11b.ew

Rommon reg:0x30004180

Running diags ...

...

When the boot is finished, enter the iOS interface and modify the startup parameters:

Switch>enable

Switch#dir Bootflash:

To view the current startup parameters:

Switch#show Bootvar

Start configuration:

Switch#configure Terminal

Enter configuration commands, one per line. End With cntl/z.

Switch (config) #no boot system Flash BOOTFLASH:CAT4000-IS-MZ.121-8A.EW

Switch (config) #boot system Flash Bootflash:cat4000-is-mz.121-11b.ew

Switch (config) #end

Save in view:

Switch#write Memory

Switch#show Bootvar

BOOT variable = bootflash:cat4000-is-mz.121-11b.ew,1

Config_file variable does not exist

Bootldr variable does not exist

Configuration Register is 0x2102

Reference Documentation:

Http://www.cisco.com/en/US/products/hw/switches/ps663/products_configuration_example09186a0080094ecf.shtml

Related Error Output:

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*                                                         *

* Welcome to Rom Monitor for ws-c4948 System. *

* Copyright (c) 2003-2007 by Cisco Systems, Inc. *

* All rights reserved. *

*                                                         *

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