Lesson 10: Cisco IOS CLI Modes
Cisco IOS is structured hierarchically, meaning commands are available only in specific modes.
The Three Primary Modes
| Mode Name | Prompt Symbol | Entry Command |
|---|---|---|
| 1. User EXEC Mode | > | Initial login (limited functions) |
| 2. Privileged EXEC Mode | # | enable from User EXEC |
| 3. Global Configuration Mode | (config)# | configure terminal from Privileged EXEC |
Configuration Sub-Modes
From Global Configuration Mode, you enter sub-modes to configure specific components:
| Sub-Mode | Prompt Example | Purpose |
|---|---|---|
| Interface Mode | (config-if)# | Configure specific ports (e.g., interface g0/1) |
| Line Mode | (config-line)# | Configure console or VTY lines (e.g., line vty 0 4) |
| Router Mode | (config-router)# | Configure routing protocols (e.g., router ospf 1) |
Essential Commands
?: Get context-sensitive help.TaborSpace: Command completion.show running-config: View the current configuration (in RAM).show startup-config: View the saved configuration (in NVRAM).copy running-config startup-config: Save the configuration (crucial!).reload: Restart the device.