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Backing Up and Restoring the Cisco IOS

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The router will reload and ask if you want to use setup mode (because no

startup-config is used). Answer No to entering setup mode, press Enter to go
into user mode, and then type enable to go into privileged mode.

Viewing and Changing the Configuration

Now you are past where you would need to enter the user mode and priv-
ileged mode passwords in a router. Copy the startup-config file to the
running-config file:

copy startup-config running-config

or use the shortcut:

copy start run

The configuration is now running in RAM (random access memory), and

you are in privileged mode, which means that you can view and change the
configuration. Although you cannot view the enable secret setting for the
password, you can change the password, as follows:

config t

enable secret todd

Resetting the Configuration Register and Reloading the
Router

After you are finished changing passwords, set the configuration register
back to the default value with the config-register command:

config t

config-register 0x2102

Finally, save the new configuration with a copy running-config

startup-config

and reload the router.

Backing Up and Restoring the Cisco IOS

efore you upgrade or restore a Cisco IOS, you should copy the exist-

ing file to a TFTP host as a backup in case the new image does not work.

You can use any TFTP host to perform this function. By default, the flash

memory in a router is used to store the Cisco IOS. The following sections
describe how to check the amount of flash memory, copy the Cisco IOS from
flash memory to a TFTP host, and then copy the IOS from a TFTP host
to flash memory.

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