Making configuration changes

Making configuration changes
3.1.6 This page will explain how configuration variables can be changed in different modes.

If a configuration requires modification, go to the appropriate mode and enter the proper command. For example, if an interface must be enabled, enter global configuration mode, enter interface mode, and issue the command no shutdown.

To verify changes, use the show running-config command. This command will display the current configuration. If the variables displayed are not correct, the environment can be changed in the following ways:

• Issue the no form of a configuration command.
• Reload the system to return to the original configuration file from NVRAM.
• Copy an archived configuration file from a TFTP server.
• Remove the startup configuration file with the erase startup-config, then restart the router and enter setup mode.

To save the configuration variables to the startup configuration file in NVRAM, enter the following command at the privileged EXEC prompt:

Router#copy running-config startup-config

The next page will teach students how to configure an Ethernet interface

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