Cisco Switch Fails to Boot to new IOS Once .tar package is uploaded

This tutorial explains how to remove a IOS from ROMMON mode that is causing the switch not to boot


Here we can see that the Switch is failing to load IOS

BIN file was part of the .tar package that we uploaded to the router

The first step is to make sure that we are booting from the correct IOS so we can look at the contents of the flash with the following command

to look in the directory where the new IOS is located


z.150-2.SE2.bin is the name of the new IOS that we uploaded and want to boot from so this can be done via the following command


Delete the offending IOS

The switch will now attempt to boot from the IOS that we have selected. Should this then fail, we need to consider that we have a corrupt or incompatible IOS so we need to set it to boot from the other IOS or we need to remove the potentially corrupt IOS

to delete the offending IOS we can issue the following command


lt will now boot from the good IOS



The reason for this is that the switch will not be able to find the IOS we deleted so now has to revert to the original IOS


Now we can boot into the original IOS we have more commands and capability available to us. including being able to remove the original.tar folder that we uploaded originally


This can be done by looking at the directory

the directory we want to delete. in this example ‘c2960s-universalk9-mz.150-2.SE2’ and enter the following command

the 2 switch commands that we are using here do the following


The switch is now in a state that it initially was before we uploaded the new .tar package, in this example ‘c2960s-universalk9-tar.150-2.SE2.tar’

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