Cisco IOS CLI for beginners - Part 1

okay this is a beginners tutorial on the Cisco IOS and command-line interface and how to run commands on a router so first of all we'll start with a router so I'll click on routers here I'll grab a generic router the first generic router right here then n devices and you get a PC and what we're going to do is we're going to say pretend this is a brand new router and we've got a computer here we're going to make a console connection to the router so we'll go to connections we'll grab a console port or console cable and we'll attach it to the serial port on the computer and then drag up and then click on the router and then click on the console port and so this is a virtual console connection from a PC to a router okay and now we can also virtually set up a terminal session to the router so click on the PC and we'll go to desktop and you'll see that terminal is an emulator for a hyper terminal typically on a computer also you could use on your computer you could use putty if you wanted to set up a console connection to your router so we'll just click on terminal it's got the default configurations already set for you so all you have to do is click OK and what you're left with is a dialog screen that you would see on a if you had a brand new router out of the box with basically an empty configuration file or no configuration file and you can see here that the the router has booted you can see here the bootstrap and then some some copyright information some opening information and then here at the bottom it says system configuration dialog now this is a wizard that will walk you through step by step configuring an initial configuration of your router but typically in Cisco class you don't use this line by line wizard for configuring your router so we'll just type in no here so I've typed in no and hit enter and then you just you'll see a please return to get started message and press return and there you are you're left with a prompt it says router with the user privileged or user exact mode prompt right there okay and so it's ready to take commands so even though this PC virtual terminal connection is really great and it looks like we're configuring this router I could probably get this text a little bit bigger for in the interests of the video tutorial by just clicking on the router and then clicking on command-line interface and I've set they fought to be a little bit bigger which I think works better for the tutorial so I'm going to just use the routers virtual command-line interface so press return and I can keep pressing return here and this is the user exact prompt right this greater than sign and if I want to get to the different command modes so this is the basic command mode in this command mode what we can do is before we do that I'll just type in a question mark and it shows me all of the commands that are available in this basic level user exec command mode so you can see I can run a telnet command I could run an SSH command I have access to a few of the show commands right let's take a look at that so we'll type in show and then space and then a question mark and you can see here that I can do a show ARP show CDP right but I cannot do a show running configuration or startup configuration but I can do a show version command so I have access to some of the show commands also if I type question mark again and hit enter you can see here that I have access to the ping command and and then if I want to get to a more privileged mode see it says here turn on privileged commands I can type enable and to get to a higher mode command mode on the router so that's what I'll do here I'll type in enable and hit enter and now the prompt changes from a greater than sign to a pound sign which indicates that I'm now in privileged exec mode privileged user mode okay so now in privileged exec mode I have access to even more commands so if you type question mark you'll see that the commands run through to another screen if I want to see that the rest of the screen or the rest of the commands I can hit enter and look at them line by line or I can hit the spacebar to look at another screen worth of the commands and so then these are all the commands that you have available to you in in privileged exec mode and then to get to a configuration mode or what's called global configuration mode you type in configure space terminal and hit enter and then you'll see the word config in between parentheses and then a pound sign and that indicates that indicates that you are in global configuration mode and this is the mode that you could use to change the router name to configure your interfaces to turn on routing protocols you name all kinds of stuff for instance if I want to change this the name of this router to let's see here so you type in hostname write hostname and then if you're not sure what the rest of the command is you'll just hit a space and type question mark and then it tells you a word you need a word the systems networks name so it tells you exactly what to do so what I'll do is I'll just type in the name I'll type in Dan's courses and now the routers name is dance courses or I could type in hostname r1 which is something you typically see and now the routers hostname is r1 okay now - now that we have changed the routers hostname we want to save this to the configuration file and to do that what I'm going to do is is I'm going to exit out of this mode and go back to privileged mode and to do that what I can do is I can just hit ctrl C which will take me out of that mode and I can hit enter and again and now you see here I'm back in privileged mode and now I want to save that configuration so I'm going to say copy running and I'm going to do another thing here I've typed in run and then I'm going to hit tab and then it tab completes to the full command which is running - config right so I'm going to copy the running configuration running config space and I'll type Sta and then I'll hit tab and it tab completion finishes it for me finishes the command for me which is startup config and this command will copy the running configuration file in RAM to the startup configuration file which is saved in NVRAM or non-volatile Ram so if I do that it'll ask me the destination file name I can give it a file name here or it can accept the default which is start up - config and that's what we usually do in class is accept the default hit enter and it builds the configuration file and I've saved the configuration file so now if I was to restart the router the the configuration the hostname r1 will be saved the router command line interface reminds me a lot of a Linux terminal command line interface so if I want to go back in the history of the commands that I've used on each command mode all I have to do is hit up arrow and it will cycle through as I keep hitting up arrow it'll cycle through the commands that I've used in my history that's another one of the features that it has if I want to look at my run in configuration file which is something that do quite a bit I'm going to type a show show commands are very important if you want to see all of the show commands from privileged exec mode you type in show and then space and then a question mark but in this case I'm just going to say I want to show the run I'm going to hit tab completion show the running configuration and this shows me the running configuration file so the running configuration file is shows me the version of essentially the I believe that's the version of the iOS it shows me a couple of default commands that are in the configuration file by default notice the hostname r1 and then not much else if I hit more spacebar you can see that I have interfaces here for instance interface fastethernet 0/0 fastethernet one zero but there's no IP address and the interface has been shut down so administratively shut down by default I'm going to hit more again spacebar and you can see here that we have administrative interfaces we have line console 0 this is my console connection which I can configure and this is line virtual terminal this is how this is an administrative configuration or administrative interface for telnet or SSH and you can see line vty you have 0 space for that means I have I can set up five or configure five virtual terminals that I can connect to the router with so we'll be showing I'll be showing you how to configure those as well I'll hit more again spacebar and

Channel: danscourses

Views: 387,077

Rating: 4.9079452 out of 5

Keywords: CLI, IOS, Cisco, CCNA, beginner

Id: -zvihHxrfzM

Length: 10min 37sec (637 seconds)

Published: Sat Oct 08 2011