Cisco Certified Network Associate (CCNA) 2025 – 400 Free Practice Questions to Pass the Exam

The command 'copy run start' is used on a Cisco router to save the current running configuration to the startup configuration file. This action ensures that any configuration changes made during the current session are preserved when the router is rebooted. The startup configuration is the one that the router loads upon startup, while the running configuration is the configuration currently in use.

The command establishes a crucial backup mechanism; by copying the running configuration to the startup configuration, you effectively create a safeguard against data loss. In a scenario where the router is powered off or restarted, the saved configuration in the startup file will be loaded, allowing the router to return to its last operational state.

Understanding this command is fundamental for network management, as it ensures that all configuration changes are not lost upon a reset. This practice not only assists in maintaining network stability but also aids in the recovery process should a configuration need to be reverted.