There are following primary modes of operation in IOS.
- Setup Mode
- User Exec Mode
- Privileged Exec Mode
- Global Configuration Mode
- Interface Configuration Mode
- Rommon Mode
- In router or switches, all configurations are saved in NVRAM.
- If there is no any router’s configuration saved in NVRAM means NVRAM is blank then it shows a message given below:
Continue with configuration dialog [yes/no]:
To enter in setup mode, type “y” for yes.
If initial configurations are saved in NVRAM, then you can’t enter in the setup mode.
User Exec Mode
- It is the primary mode when you log in router or switch.
- By default, you can access this mode directly (without password).
- It consists of device hostname followed by greater than (>) sign.
- For router default hostname is Router. For switch default hostname is Switch.
| Router> |
To see list of commands available in User exec mode, type command “Router>?”
Privileged Exec Mode
- It can be accessed by typing enable command at user exec mode.
- By default, it consists of device hostname followed by “#” symbol.
- This mode allows you to execute all available exec commands.
- To see list of commands available in Privileged exec mode, use the command “Router#?”
- If you want to move back to the user mode, type disables command.
Global Configuration Mode
- It is used to configure the device globally.
- Type configure terminal command at privilege mode to access global configuration mode.
- It allows you to make changes in the running configuration.
- By default, it consists device name followed by (config)#.
- To see all commands used in global configuration mode, you can use “Router(config)?”
- If you want to move back to privilege exec mode, use “exit” command.
Interface Configuration mode
- This mode is used to configure interfaces like Serial interface port (s0/0/0, s0/0/1, so on), and Fast Ethernet interface port (f0/0, f0/1, so on).
- We provide IP addresses to each interface through which the device is connected.
- To see all commands used in interface configuration mode, you can use “Router(config-if)?” Command.
- If you want to move back to the Global configuration mode, use “exit” command.
- This mode is used for diagnostic purpose.
- By default, the router does not enter in rommon mode.
- To manually enter in this mode, type reload command at privileged exec mode and then press CTRL+C key to enter in rommon mode.
Cisco IOS mode Summary
|Mode||Purpose||Prompt||Command to enter||Command to exit|
|Setup||Router use setup mode to create an initial configuration, if the running configuration is not present||Parameter[Parameter: Value]:||Router will automatically Insert in this mode if running Configuration is not present.||Press Ctrl+C Command to exit.|
|User EXEC||It allows you to connect remote devices, and allow authorized users to configure and manage the router or switches.||Router >||Default mode after booting. Login with the password, if configured.||Use exit command|
|Privileged EXEC||It includes high-level testing and list of commands like show, copy, and debug.||Router#||Use enable command at user exec mode||Use exit command|
|Global Configuration||It allows users to modify the running system configuration.||Router(config)#||Use configure terminalcommand at privileged exec mode.||Use exit command|
|Interface Configuration||It allows users to modify the Operation of an interface.||Router(config-if)#||Use interface type number command at global configuration mode.||Use the exit command to return in global configuration mode.|
|ROMMON||It allows you to Perform low- Level Diagnostics.||ROMMON>||Enter reload command at Privileged exec Mode.||Use exit Command.|