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bootflash question

schoychidl
Level 1
Level 1

Hi,

I am a Cisco rookie with very little Cisco experience.  We have a Catalyst 4506-e switch that boots occasionally reboots into ROMmon mode (while in ROMmon mode, manually booting to the correct bootflash file will result in a proper boot)..  All other 4506-e's boot fine.  Doing basic investigation and compairing results of show run-config gives these results:

Good switches:

service sequence-numbers

!

hostname xxxxxxxx

!

boot-start-marker

boot-end-marker

!

logging buffered

Bad switch:

service sequence-numbers

!

hostname xxxxxxxxx

!

boot-start-marker

boot bootstrap bootflash:

boot system flash bootflash:cat4500e-ipbasek9-mz.122-53.sg2.bin

boot system flash bootslash:cat4500e-ipbasek9-mz.122-53.SG.bin

boot system flash bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin

boot bootldr bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin

boot-end-marker

!

logging buffered

The correct bootflash: is in bold above.

Also, dir bootflash: gives these results:

Good switches:

Directory of bootflash:/

    6  -rw-    24678948  May 18 2010 07:01:52 -04:00  cat4500e-ipbasek9-mz.122-53.SG2.bin

128282624 bytes total (96129024 bytes free)

Bad switch

Directory of bootflash:/

    6  -rw-       34033   Dec 8 2011 11:21:34 -05:00  10.14.2.14

    7  -rw-    24678948   Aug 2 2012 11:21:58 -04:00  cat4500e-ipbasek9-mz.122-53.SG2.bin

    8  -rw-    24678948  May 18 2010 07:09:54 -04:00  cat4500e-ipbasek9-mz.122-53.SG2OLD.bin

128282624 bytes total (71397376 bytes free)

Does this information help diagnose why the bad switch will reboot in ROMmon mode?  If you are able to provide help, I would sincerely appreciate step-by-step instructions for any fix.  I'm still learning my way around the Cisco environment.


4 Replies 4

Arumugam Muthaiah
Cisco Employee
Cisco Employee

Hi,

The switch could wind up in ROMmon mode due to these reason

  • A switch reload or crash after the image was corrupted or deleted
  • The Compact Flash which holds the system image has been removed
  • The configuration register has been changed incorrectly. The configuration register value of 0x0 always brings the switch to ROMmon mode. The typical configuration register is 0x2102, with the boot system flash command pointing to the system image to load
  • The boot variable is incorrect, but a valid image is still present

Suggestion:

  • Issue the show bootvar command to check the current boot variable

Switch#show bootvar

BOOT variable = bootflash:cat4000-is-mz.121-8a.Ew,1

CONFIG_FILE variable does not exist

BOOTLDR variable does not exist

Configuration register is 0x2102

  • Remove the existing incorrect boot variable and add the correct one. Issue the configure terminal command in order to do this.

Switch#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Switch(config)#no boot system flash bootflash:cat4500e-ipbasek9-mz.122-53.sg2.bin

Switch(config)#no boot system flash bootslash:cat4500e-ipbasek9-mz.122-53.SG.bin

Switch(config)#boot system flash bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin
Switch(config)#end

  • Save the configuration from running to startup, by issuing the write memory command.

Switch#write memory

Building configuration...

Compressed configuration from 4359 bytes to 1730 bytes[OK]

Switch#

  • Check the boot variable again to make sure it is set properly so that the switch boots up the correct system file on the next reboot. Issue the show bootvar command in order to do this.

Switch#show bootvar

BOOT variable = bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin
CONFIG_FILE variable does not exist

BOOTLDR variable does not exist

Configuration register is 0x2102

Refer:

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

Regards,

Aru

*** Please rate if the post is useful ***

Regards, Aru *** Please rate if the post useful ***

Hello Aru,

Thanks for the reply and the help.  I followed your instructions explicitly.  Here's what I get at show bootvar:

show bootvar

BOOT variable = bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin,1;

CONFIG_FILE variable does not exist

BOOTLDR variable = bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin

Configuration register is 0x2101

Any issue with this being different that what you expected?

Thanks for the help!

Hi,

Thanks for your kind response. If you see that the configuration register is set as 0x2101. Usually from the factory the config register is 0x2101 which means it loads the first image it finds in flash regardless of the boot statement you try to use

In your case, the switch is ignoring your boot statement

boot system flash bootflash:cat4500e-ipbasek9-mz.122-53.sg2.bin

boot system flash bootslash:cat4500e-ipbasek9-mz.122-53.SG.bin

boot system flash bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin

boot bootldr bootflash:cat4500e-ipbasek9-mz.122-53.SG2.bin

When you do a "sh bootflash: the image that is on top is the one that will load with a 0x2101 register.

Directory of bootflash:/

    6  -rw-       34033   Dec 8 2011 11:21:34 -05:00  10.14.2.14

    7  -rw-    24678948   Aug 2 2012 11:21:58 -04:00  cat4500e-ipbasek9-mz.122-53.SG2.bin

    8  -rw-    24678948  May 18 2010 07:09:54 -04:00  cat4500e-ipbasek9-mz.122-53.SG2OLD.bin

Suggestion:

Please change the config register as 0x2102 which will use the image you specify in the boot statement

Refer:

http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a008022493f.shtml

Regards,

Aru

Regards, Aru *** Please rate if the post useful ***

Thank you Aru,

That fixed my issue today so thank you for posting this easy to follow solution!

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