How to check the configuration of a core switch

You can view a core switch's configuration using commands like show running-config for the active configuration and show startup-config for the saved configuration.

Accessing the Switch

To view the configuration, first connect to the switch via console cable, SSH, or Telnet. Use a terminal emulator like PuTTY and log in with the appropriate credentials. Ensure you have privileged EXEC mode access (enable mode) to run configuration commands.

Key Commands to View Configurationshow running-config: Displays the current active configuration in RAM, including VLANs, interface settings, and security parameters.show startup-config: Shows the configuration stored in NVRAM that will load on the next reboot.show version: Provides switch model, IOS version, uptime, and memory information.show vlan brief: Lists all VLANs configured on the switch and their status.show interfaces / show ip interface brief: Displays interface status, IP addresses, and operational state.show mac address-table: Shows learned MAC addresses and associated ports.show spanning-tree: Displays STP status to prevent network loops.show inventory / show environment: Checks hardware components, power supplies, and environmental health.

Additional Tips

Use context-sensitive help by typing? after a command to see available options. For VLAN-specific details, use show vlan id or show interfaces trunk to verify trunking. To ensure changes are saved, compare running-config with startup-config and use copy running-config startup-config if needed.

By systematically using these commands, you can fully inspect the core switch's configuration, verify VLANs, interface settings, and security policies, and ensure the switch is operating as intended.