|  | 12.1 | Initial Router Configuration
| 12.1.1 | Setup mode

After testing the hardware and loading the Cisco IOS system image, the router finds and applies the configuration statements. These entries provide the router with details about router-specific attributes, protocol functions, and interface addresses. However, if the router is unable to locate a valid startup-config file, it enters an initial router configuration mode called setup mode. With the setup mode command facility, you can answer questions in the system configuration dialog. This facility prompts you for basic configuration information. The answers you enter allow the router to use a sufficient, but minimal-feature, router configuration that includes the following: an inventory of interfaces an opportunity to enter global parameters an opportunity to enter interface parameters a setup script review an opportunity to indicate whether you want the router to use this configuration After you approve setup mode entries, the router uses the entries as a running configuration. The router also stores the configuration in NVRAM as a new startup-config, and you can start using the router. For additional protocol and interface changes, you can use the enable mode and enter the command configure.