Cisco routers run an operating system, called IOS. Like any operating system, IOS includes a command language to enable equipment owners to retrieve information and change the device’s settings. One of the most powerful commands in IOS is show. This command retrieves information. This guide gives you information on the most important data that you can get out of your router with the show command.
Help
Before we discuss the main subject of this guide, there is one very helpful little tool in the Cisco operating system that you should know about. This is the help command, which is typed as ?. If you type ? at the command prompt, you will get a list of all available commands in the operating system. If you type a command and follow it with ? (like show ?) you will get an explanation of the parameters for that command. Some commands have several different purposes that are tailored by a second word. You can get specific help for that branch of command by typing ? after it. For example, show ip ? will show you all of the information options that relate to IP data.
Cisco show command cheat sheet
The following table lists the show commands that you are most likely to use in your day-to-day administration tasks.
Further reading
There are a lot more show commands than those listed in this guide. For a definitive list, take a look at the Cisco IOS Configuration Fundamentals Command Reference. You can also read our Cisco Discovery Protocol tutorial.
