Cisco Systems Cisco 12816 Manuale Utente

The configuration modes allow you to make changes to the running configuration 
file. If you save the configuration, the commands are stored and persist across 
router reboots. In order to access the various configuration modes, you must start 
from global configuration mode. From global configuration mode, you can enter 
interface configuration mode, subinterface configuration mode, and a variety of 
protocol-specific modes.

ROM monitor mode, described earlier in this chapter, is a separate mode used 
when the router cannot boot properly. If your router does not find a valid system 
image when it is booting, or if its configuration file is corrupted at startup, the 
system typically enters ROM monitor mode.

After the system boots successfully and loads the Cisco IOS software, the user 
EXEC mode prompt appears on the system console. The user EXEC mode prompt 
consists of the router host name followed by the right angle bracket (>). The 
following example shows the user EXEC mode prompt for a router with the 
factory default name Router.

Router>

The default host name is 

Router

 unless it was changed during initial configuration 

using the setup command facility.

To enter privileged EXEC mode, enter the enable command at the user EXEC 
mode prompt. If the enable secret password is set and saved in memory, the 
system prompts you to enter the enable secret password. The password does not 
appear on the window and is case sensitive. When the system accepts the 
password, the prompt changes to the privileged EXEC mode prompt, which 
consists of the router host name followed by the pound sign (#).

Because many of the privileged commands set operating parameters, privileged 
access should be password-protected to prevent unauthorized use.