| Explanation & Hint:
In the show running-config command, the part of the syntax represented by running-config is a keyword. Let’s explore each option in detail to understand their roles and how they relate to the command structure.
Option 1: The Command
Definition: A command in the context of Cisco IOS (Internetwork Operating System) refers to an instruction given by a user to perform a specific action or retrieve certain information from the device.
Example: In the show running-config command, the entire phrase is considered the command. The show keyword tells the device to display certain information, and running-config specifies what information to display. The show running-config command instructs the device to display the current active configuration running on the device. This configuration includes all the settings that are currently in effect.
Detail: Commands in Cisco IOS are hierarchical and can be simple or complex. They often start with a keyword that describes the action (show, configure, interface, etc.), followed by parameters or sub-commands that specify the details of the action. For instance, show ip interface brief is another command where show is the action keyword and ip interface brief specifies the detail of the information to display.
Option 2: A Keyword
Definition: A keyword in Cisco IOS is a predefined word that has a specific meaning within the context of the command structure. Keywords are used to define the actions and parameters of commands.
Example: In the show running-config command, running-config is a keyword. It indicates to the IOS what specific information is being requested.
Detail: Keywords are essential building blocks of Cisco IOS commands. They make the commands human-readable and understandable. For example:
show: This keyword is used to display information.interface: Used to enter interface configuration mode.ip: Often used to specify actions or configurations related to IP protocols.
In show running-config, running-config tells the system to display the current configuration stored in RAM (Random Access Memory), which is actively being used by the device.
Option 3: A Variable
Definition: A variable in the context of Cisco IOS commands refers to a user-defined value or a placeholder that can change. Variables allow for flexibility and specificity in commands.
Example: In a command like ping [destination IP address], the [destination IP address] is a variable where the user inputs the specific IP address they want to ping.
Detail: Variables are not static; they change based on the user’s input. For instance:
- In the command
interface [interface ID], the [interface ID] is a variable where you might specify GigabitEthernet0/1.
- Variables enable the customization of commands to suit specific needs, such as targeting a specific interface or IP address.
In the show running-config command, there are no variables. The entire command is a fixed set of keywords.
Option 4: A Prompt
Definition: A prompt in Cisco IOS is the text or symbol displayed to the user, indicating that the device is ready to accept commands. Prompts change based on the mode the user is in (User EXEC, Privileged EXEC, Global Configuration, etc.).
Example: Typical prompts include:
Router>: Indicates User EXEC mode.Router#: Indicates Privileged EXEC mode.Router(config)#: Indicates Global Configuration mode.
Detail: Prompts are essential for navigation and context within the CLI (Command Line Interface). They inform the user of the current mode and readiness to accept commands. For example:
Router(config-if)#: Indicates interface configuration mode.Router(vty)#: Indicates line vty configuration mode.
In the show running-config command, running-config is not a prompt. The prompt is what you see before entering the command, such as Router#.
Conclusion
In summary, the show running-config command involves the following elements:
- The Command: The entire phrase instructs the device to perform an action.
- A Keyword:
running-config is a keyword specifying what the show command should display.
- A Variable: Not applicable in this command as
running-config is not user-defined or changeable.
- A Prompt: Not part of the command itself but what precedes it in the CLI.
Therefore, running-config in the show running-config command is best described as a keyword. It is a predefined term that tells the IOS to display the current configuration running on the device. This configuration is stored in RAM and reflects all active settings and commands that are currently in use. |