4.9. Manage IOS configuration files (including save, edit, upgrade, restore)
Any changes that you make to the router configuration are stored in the running-config file. And if you don't enter a copy run start command after you make a change to running-config, that change will go poof if the router reboots or gets powered down. So, you probably want to make another backup of the configuration information just in case the router or switch completely dies on you. Even if your machine is healthy and happy, it's good to have for reference and documentation reasons.
In the following sections, I'll describe how to copy the configuration of a router to a TFTP server and how to restore that configuration.