Modes
User EXEC ……………………Device>
Privileged EXEC……………. Device#
Global Config…………. …….Device(config)#
Interface Config…………… Device(config-if)#
Line Config………….. ………Device(config-line)
?
One of the most useful commands in cisco ios. The Question mark represents basically a help function. When you cant remember the next command in line use the ? it will show all available commands that can follow.
Show Running-Configuration
This shows the current configuration of the Router, Switch, Firewall.
This is extremely handy when troubleshooting configurations, every time you save a configuration it amends the current Running-Configuration
copy running-configuration startup-configuration
This saves your work to NVRAM (Non-volatile RAM).
Show Interface
This will show information on the interface you wish to display.
For example show interface fastethernet 0/0
With this command you are able to get numerous information about an interface such as the status of the port, (up/down), Protocol Status.
enable
moves you to Privilege Exec mode
Configure Terminal
This allows you to change global parameters
Shut or No Shut
Shuts interface down , No shut brings interface up
Debug
This command is used for troubleshooting. Be careful if using in production Network as it can generate a lot of information and hamper if not bring down routers/switches by the amount of information it needs to generate.