4.10. Manage Cisco IOS

Before you upgrade or restore a Cisco IOS, you really should copy the existing file to a TFTP host as a backup just in case the new image crashes and burns.

And you can use any TFTP host to accomplish this. By default, the flash memory in a router is used to store the Cisco IOS. In the following sections, I'll describe how to check the amount of flash memory, how to copy the Cisco IOS from flash memory to a TFTP host, and how to copy the IOS from a TFTP host to flash memory.


To learn how to use the Cisco IFS, please see Chapter 5 of the Sybex CCNA Study Guide 6th Edition.

But before you back up an IOS image to a network server on your intranet, you've got to do these three things:

  • Make sure that you can access the ...

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