Networking Basics: Understanding the \"copy running-config startup-config\" Command

What is the purpose of the command \"copy running-config startup-config\" on a Cisco router?

After making changes to the router configuration and issuing the command, what will happen?

Answer:

When the command "copy running-config startup-config" is executed on a Cisco router, it saves the changes made to the running configuration to the non-volatile RAM (NVRAM). This ensures that the changes will persist even after a reboot of the router.

In networking, routers and switches are vital components that require configuration to operate effectively. The running configuration of a router refers to the current configuration settings that are in use by the device. This configuration is stored in volatile memory, meaning it is lost when the device is powered off or restarted.

By issuing the "copy running-config startup-config" command, the network administrator is essentially saving the current configuration to the NVRAM of the router. The startup configuration is the configuration that is loaded when the router boots up, and by copying the running configuration to the startup configuration, the changes made by the administrator will be retained.

This command is crucial for ensuring that any configuration changes made to the router are saved and applied persistently. It's a best practice to save the running configuration to the startup configuration after making changes to prevent any loss of configurations in case of unexpected reboots or power outages.