Cisco Networking: Global Configuration Mode

By Edward Tetz from Cisco Networking All-in-One For Dummies

To configure a Cisco network device you must enter the Global Configuration operating mode. After passing thru the User EXEC and Privilege EXEC modes you enter the Global Configuration mode by entering the configure command.

When you type the configure command, you need to specify how you will make configuration changes. The most common manner of configuring devices is by using the terminal, so you use the configure terminal or conf t (for configure terminal) commands. The Global Configuration mode appears, and your command prompt will look something like this:

Router(config)#

This prompt is identified by the (config), which is in the prompt. You also have a different list of commands that you can type. Here is just a sample of the commands at this level:

access-list: Manage Access Control Lists (ACLs) to restrict network connections to, from, or through the device you are connected to.
arp: Manage the Address Resolution Protocol (ARP) cache on the device you are connected to.
banner: Set a logon banner to issue a security warning to users connecting to the device you are connected to.
boot: Configure or modify the system boot parameters, such as the IOS version that will be used.
cdp: Cisco Discovery Protocol (CDP) tells you what is connected to you on network interfaces. CDP allows you to view this information.
clock: Allows you to change the system clock.
config-register (router only): Set the configuration register, which is the location in memory that stores a pointer to the system configuration information.
enable: Sets or changes enable passwords.
exit: Exits Global Configuration mode.
hostname: Sets the device hostname.
ip: Enters the IP configuration subcommands.
interface: Selects an interface for configuration.
no: Negates another command that has been issued.
prompt: Sets the devices command prompt.