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Boot Variable


what does this Mean 

SW-CORE#show bootvar
BOOT variable =
CONFIG_FILE variable does not exist
BOOTLDR variable does not exist
Configuration register is 0x2141

Standby BOOT variable =
Standby CONFIG_FILE variable does not exist
Standby BOOTLDR variable does not exist
Standby Configuration register is 0x2141

Hall of Fame Super Gold

If this is taken from a

If this is taken from a chassis-based switch, then the config-register is incorrect.  


There are TWO config-register value for chassis-based systems.  They are:  


  • 0x2101 - This config-register value means "ignore boot variable string option and boot the first available IOS from the flash/bootflash". 
  • 0x2102 - This means boot the IOS found in the boot variable string.  


Now there are different pros and cons to either these two.  If you don't know how to or you are unsure if your boot variable string is correct or not (and you don't want to find out the hard way) then using 0x2101 is OK. 


If you are using 0x2102 and you've got the wrong boot variable string or no boot variable string, the switch will boot into ROMmon.


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Hall of Fame Super Gold

To the OP:  I have no idea

To the OP: 


I have no idea what you are doing or what you are trying to do.  You really need to READ AND UNDERSTAND our responses.  Go here: