Original subtitles

>> Working with the Cisco IOS.

Can I side tangent?

[laughs] I know you're like, you can't side tangent

until you have something to side tangent from.

You haven't even started.

I know, I know but I just have this thought and I-- the topic is kind of around the--

you know I always get the question, people are saying, well, how do I get into the Cisco career

or how do I open doors or how do I-- you know, how do I be successful in this career?

So I have this thought in my-- I think I've got an answer to that in a nutshell.

So-- so today is November 27th, 2012.

It is kind of the Christmas season in Arizona.

It's, you know, 63 degrees outside, freezing temperature and I'm sick.

It always happens, and nothing like flu.

It's just the stuffy head and your nose, congestion, scratchy throat, you know, coughing.

You know I'm like a NyQuil commercial waiting to happen.

And so-- and you know this morning I wake up I'm like-- I'm not recording, no way.

You know I'm not feeling well.

I'm just going to make some slides, you know, create--

maybe create some labs, going to do some-- some flow of the course.

So about 15 minutes ago, I'm walking out in the kitchen making some tea and my wife goes "Wow,

you must be rough, you know, you don't even like tea,"

and then I'm like, "I know, I'm going to record."

What? What?

What? I thought you're not-- and I know, I know.

I just finished the slide for working with the Cisco IOS and I'm so excited to talk about it,

I can't even focus on what's coming next.

I can't-- and you know like I'm looking at the blank white screen and I'm like I can't even--

I can't even do stuff on it because I'm thinking so much about things I want

to say and this day I got to record.

So now here I am.

I got my cup of tea, it's hot, and it's helping me record this

and so you're going okay, what's your point?

You know we've established Jeremy's kind of odd, a little freaky.

What's the point?

Okay, so here's my point.

This is now 15 years of training for me which is weird to be able to say that

and I've gone through a lot of technology.

I didn't start in Cisco.

I started in Microsoft and Novell and then actually even before that, in college,

computer programming, computer science was my degree and I hated them.

You know, I hated computer programming when I was in college.

I was like-- so much so that I got out of college and I went to Pizza Hut because I was

so convinced that I didn't like computers that I was like, "I'm going to work

in the pizza industry and further myself there," and then I realized I didn't like pizza either.

So nonetheless every technology that I've run into always when I start into it,

I'm frustrated, I don't get it, I read it and I'm like I don't get it and I listen

to it again, I'm like I still don't get it.

You know and I reach these points from the-- you reach these decision points where like okay,

I either push through this frustration until I really get it and maybe it's listening

to a nugget again, reading it from a different book, Googling a different source,

posting to a forum and helping somebody unders--

you know, explain it to you or talking to a friend, whatever.

You reach a point where you either say, "I'm going to push through until I get this,"

or I'm just going to be like, "Ah, whatever, I'll move on to the next thing."

The more of those, "ah, whatever" moments you have, the less passion you will have towards

that technology, you might say-- you might [inaudible] why do you care?

Well, because the more passion you develop for something, the better and better

and better you're going to get at it to the point to, you know,

now I'm like, "Well, how do I get a career?"

To the point where somebody will be crazy not to hire you.

I mean I've-- I now own a company.

I've interviewed people to where, you know, that some people will come in and they're like,

"Yeah, I've gotten some experience in this field."

I'm like so, you know, describe a DHCP server and they'll-- you know textbook and well,

a DHCP server is a server that hands out IP addresses to clients and--

you know and then I'm like, okay, you got the right answer but where are you at?

[laughs] You know, I'm like you are-- like are you excited to work here?

Are you-- are you excited about this technology?

And then, you know talk to another guy who's like, "Oh man, oh man, I just--

I just finished my course at, you know, the community college or whatever and then like--

and oh man, and I think I-- you know, I haven't even done this

yet but I really have a good idea.

You know based on what you've told me that we can design it this way."

And you know I'm like, "Bro, you are on board," because I know--

I know, you know, one person is going to be looking at, "Okay, well, it's about 5 o'clock

in the afternoon, I'm done, you know.

All right, see you, see you for today."

And then I've got another guy who's like, "Man, it's 5 o'clock, I'm going home,

spend a little time with my family and then 10 o'clock I'm waking back up or I'm jumping back

in and I'm going to, you know, finish this network diagram or whatever."

So when it's like, "Well, how do I open doors in Cisco?"

I know it's kind of like well, it's the generic answer

but there's no replacing just a genuine goodness, you know, to where you're just good

at the technology and you're really excited about it

and you can apply that principle to anything.

You know, I'm talking technology now but, you know, take your marriage, you know.

You know, I am not wife certified but if I spend--

the more time I spend trying to figure out my wife, the better and better the marriage get

or your kids or, you know, fill in, you know, life circumstance and the more--

you know every life circumstance is frustrating and you have that decision.

Do I walk away and just be like, "I don't get it," you know.

Or do I really push through and become a master of that technology?

Anyway, that's how you're successful in this career.

I know it's not a-- well, you know, call this guy and he'll get you in but that will--

I guarantee you, that will open doors.

So, working with the Cisco IOS, this is-- and you know, what a great intro.

I'm almost, you know, I'm so excited.

I'm kind of like shaking.

I'm like how do I even get into the IOS in transition?

What a good intro into the foundation software of everything Cisco.

So imagine for a moment that you had never seen Microsoft Windows.

You know this-- that we would have to have an introduction saying, okay, well this is Windows,

this is a task bar, this is how you minimize and maximize

and open a program, all those kind of things.

This is what that is for Cisco, you know, essentially IOS is the Cisco operating system.

So we're going to go through and get familiar with it.

Well, let's start off with defining the Cisco IOS.

IOS stands for Internetwork Operating System.

It is the operating system that has become the standard in the world today.

Now, you might look at for instance let's take Windows and then let's take Linux

or McIntosh OS X. So Windows right now, you know I'm talking end of 2012, things may change

but Windows has a 93 percent market share in businesses in America.

You know now-- now Apple and McIntosh is kind of creating this ripple effect

to where they're like, "Oh, you're-- you've got to get on OS X," and you're like, "Oh,

but the fact remains OS X today still only has a five

to six percent market share in businesses in America."

Why? Well, because McIntosh, while amazingly cool,

I love the McIntosh operating system, nobody knows it.

It's kind of like you are really hitting a learning curve if you are familiar with Windows

and then you come over to McIntosh and you're like, you know, "Where is my IP config?"

Well, I guess I'm talking techie, you know, like "Where is my programs?

How do I get there?

How come when I save this file, it's not compatible when I e-mail it to that guy?"

I mean like all of those things hit people and frustration escalates really fast.

Now Cisco has created the IOS which is a command line operating system that is very well known

in the industry as in if you learn-- you know there's a lot of vendors out there.

Let me-- either Cisco, there's-- let's just say Foundry which actually is now bought by Brocade.

There is-- well, I'm just drawing out some vendors, 3Com, HP.

I think those two merged and whatever.

The politics of companies beside there's a lot of people who create networking stuff.

I'll even throw Juniper in-- into that mix.

Now, this is the only nugget where we will mention these kinds of companies

and then you are banned from mentioning them in the future.

But there're all kinds of companies out there and all of them

when they create their operating system for interfacing with their device,

you will find for the most part, it is very similar to the Cisco IOS.

Why? Well, in the same sense that Linux, you know or McIntosh, you know people know

if they just go way off and start creating their own world that people are going to walk in

and it's too radical of a change to where no matter how cool the operating system is

or how cool the feature is, people are going to immediately like, "Whoa,

I'm not going to go there unless there's a very"--

I mean unless you create a feature that is so cool and so irreplicable that people are like--

they're coming to you because of that feature.

I mean people aren't going to go there.

So learning how to work with the IOS is huge, not only for working with Cisco but for working

with any networking equipments in the industry.

So this software, and that's the look and feel.

You kind of see a view of it there that's kind of-- that's what the IOS looks like.

It's consistent through nearly all Cisco devices.

Now I say nearly all because Cisco has other stuff

like for instance Cisco ASA Firewalls would be one.

They cannot use the IOS on there 'cause that would be a security vulnerability.

If they found a security hole in the IOS, then it would also be true of their firewall.

So they created their own operating system through the ASA

which you will find them described as IOS like to where it's like the IOS, it feels like it

but there're some differences that are in there.

Same thing, you know, as you get into Nexus equipment.

I mean there're different families but they all kind of have that same look and feel.

Cisco's goal is that you learn it once and then use it many times.

So Cisco knows that the hardware that you buy can be replicated by anyone.

Everybody buys the same chips, same-- now of course you could say well, you know,

there's certain vendors that say well, okay, but hardware wise, people can all buy the same stuff

within a couple of years of each other.

So Cisco really differentiates itself through its software

and Cisco will describe themselves much counter and counter to most people's belief,

they will say, "We are a software company.

We are not-- our primary focus is not producing hardware 'cause hardware can be produced

by anyone."

Now the IOS and learning the command line is more powerful than any graphic interface,

which is tough when you're first getting started 'cause it's a learning curve especially

if you come from a graphic interface background and you're not used to typing in commands

to do this kind of configuration.

It's tough to move away from that world but once you learn it, you're kind of like, wow.

You know, you reach the point where-- even if you have a point and click GUI for instance,

there are things now-- Cisco has the SDM GUI to manage devices.

That can accomplish almost-- well, most major things.

But I just don't use it at all not because it's a bad interface

but because I find myself facing a learning curve again to where I'm like, okay,

I know if I'm in the command line I would type config T, interface that, do this, do this,

do this and I'm done, whereas here I'm going, "Where is that again?

You know, is it in this Window?

No, no, okay."

So you know, people will obviously gravitate to whatever they know.

To learn the Cisco IOS, there's no replacing seeing it and doing it and actually interacting

with the operating system itself.

So that's what we're going to do for the rest of the nugget, it's just kind of work in there.

So this is a review slide.

This is what the whole last nugget was about, so I won't go through it all again

but in essence this is what I've done.

Grabbed the console cable, plugged it into the serial port of my PC, grabbed that end,

connect it to the console port of the switch, booted up my terminal program

which I'm actually using Tera Term, but any one of those will do, and then set the serial port

to the settings and now we're good.

Now I'm actually using Tera Term, which is my nice black window.

And I reach down here and plug in-- plug in the switch.

Couple items of notes, switches, while we're waiting for this guy to boot,

switches don't usually have power switches.

Essentially if you plug it in, it is on and working, whereas routers on the other hand,

usually do have power switches so you can turn them on and off and that kind

of thing without disconnecting the power.

Also, I'm using right now a Cisco Catalyst 3550 Switch which is a phenomenal lab switch.

You can get them now fairly inexpensive

because this switches a layer two and a layer three switch.

Now, we'll talk about layer three switching a little bit later.

It's actually not officially part of this series but it's so valuable that I want to bring it

in 'cause you're going to run into it everywhere.

And so, it can do routing and switching together.

So, what a great device.

So right now, what's happening is let's just think of this as its power on self test,

you know, just like your computer where it's like checking memory.

We saw this in the last nugget, it's taking that IOS, that's the image,

there is your file name right there and it's copying it over to memory.

It's decompressing that guy from flash into RAM.

Now once that process completes, then it's going to go through

and actually start running the IOS.

It's going to look for any configuration file that it has.

If-- you know, to see if this device has been previously configured,

and if so we'll apply that.

But eventually it's going to end at either--

either number one, a prompt where you can just start typing in commands or it's going to end

in a question that will say, "Do you want to enter initial config dialogue?"

That question, first off I will say means you have no configuration,

like this device has been erased or it's brand new and it's never been configured before.

Second thing I'll say about that is when you see that question, always answer no.

Now a little side note as this comes up.

This is the model number of the switch I have, and it's actually a 24-port power, PWR.

That means it's inline power, as in if I plug-in IP phones or wireless access points

or video camera, they can actually get their power,

their electricity from the Ethernet cable on this device.

It's really, really cool.

Now, here's-- this is great.

So here's the question, I said you always want answer no to that question

and all of a sudden you see [inaudible] like whoa, what just happened there?

What those are are status messages or some people will call them syslog messages

that are coming through letting you know, "Hey,

these are things that are happening in your software right now."

It's kind of like a log file.

Now, if you're not used to those, well, I'll say get used to those, they'll happen all the time,

but initially they may frustrate you.

They may be like well, you know, I'm supposed to be typing up here

but my cursor is blinking right here, what do I do?

Well, usually if you hit the tab key, now it's not going to work

at this point 'cause it's asking me a question, but hitting the tab key

on the keyboard will repaint whatever you were typing.

So if this cut what you were typing in half, hitting the tab key will fix that for you,

and I'll explain that more later.

But for now I'm just going to hit the enter key 'cause I know it's going to keep asking me

that question until I either say yes or no.

So I'll type in no, always answer no in that case.

No. You might be thinking, what is that?

What if I would answer yes?

Well, what that is, is kind of an initial setup wizard that Cisco has created from moons ago.

I mean it's going to walk you through configuring protocols

that just don't exist anymore, things that we just don't use anymore.

It will walk you through configuring like IPX/XPX, AppleTalk,

I mean things that just aren't normal for us to use.

Instead, we want to configure the switch or router, you know,

'cause they both use these same commands and same configuration.

Configure the switch or the router manually using the different modes that are there,

and that's the big-- the big topics that I want to talk about.

So, these are the modes of configuration of Cisco IOS.

But before we even dive into that, let me go back to the-- back to the switch.

My window closed.

So I'm back in the switch so this is, you know, after I've hit enter a couple of times,

it comes up to this prompt which is considered user mode.

In user mode, you can do some limited commands.

You can work with the switch, you know, and view some of the configuration

but you can't even view all of it, it's just--

it's a very limited mode for just basic reconnaissance like let's see what's going on.

So before we start navigating to the different modes, let's get familiar, okay.

I'm sitting here, what do I type?

How do I type it?

Well that-- that leads me to I would say the biggest thing

that made Cisco famous is their help system.

At any point, no matter where you are in the configuration, you can hit the question mark

on the keyboard and it will give you a list of the commands that you're able to type in.

So I'll go, okay, well I'm in user mode, what do I do?

I hit question mark, I'm like, oh, well these are all things that I'm able to do.

Oh, look, I can ping something.

I can make sure that it's online or I can-- I can show something.

I can view some kind of configuration from this device or I can SSH-- start an SSH session to--

I mean these are all things we haven't talked about yet

but these are the commands that you're able to do.

Now you might say, okay, well-- okay, maybe I want to ping something so I type

in ping and I go, okay, is that it?

Well, at anytime you can do ping and then do, you know, space question mark

and it will give you the commands that relate to ping.

So let's say, okay, well you can either type in a word.

Now anytime and here's-- here's a good rule for you, anytime you see something in all capitals

in the help menu, that means it's a variable, like type something in there.

You don't actually type in word in all capitals, they're saying what do you want to put in?

You ping the destination address or host name.

So maybe I want to say ping 4.2.2.2 as an IP address

or ping google.com, you know, would be something.

So it's saying, you know, we can type anything there.

Or it says you can either type an IP, which would be fine.

I can type in ping IP and I go, okay, well what comes after that?

Hit the question mark and it says, okay,

well type in whatever address you want to type in now.

Now you might say, "Well, couldn't I have done that by just typing it here?

I mean do I have to type an IP as well?"

Well no, sometimes there will be multiple ways of accomplishing the same thing

in the Cisco IOS and this is an example.

Ping and then IP address or name is the same thing as ping IP in the IP address or the name.

But notice you can also go different directions.

I could say ping IPv6 and then it says, okay, well, what IPv6--

that's TCP/IP version 6, the next version of TCP/IP.

What TCP/IP version 6 address do you want to ping?

Or, you know, the list goes on and on.

So, let me first off say, there is no shame in using the question mark at all,

whether you're in production or even on the certification exam.

You will have simulations where the question mark is absolutely valid and a lot

of times Cisco wants you to go that direction because there are literally millions

of combinations of commands in the Cisco IOS.

Don't let that discourage you, let that encourage you because you have a question mark

that will really walk you through it.

You know in Windows-- in Windows if you are doing something,

most of the time they have a Wizard, right?

You open it up, it's like, okay, you're going to install this program.

What-- where do you want to install?

You put in C colon backslash program files and then you hit next, right?

And then, oh, what options do you want?

Next. And then, you know, whatever, you know it's kind of like next, next.

Your people say it all the time, next, next, next, next, finish and you're done.

Well, think of the question mark as your next command to where you're going.

Okay, well I want to, you know, now this is, you know, I want to do something with Crypto,

you know, the encryption-related commands up there and I go, well, you know, what do I do?

Well, here's your next button, I just hit next.

It says, okay, well I need to type in key, you know, there's not much else I can do here.

Next. And then it says, okay, well do you want that in?

So, it's asking me these options.

Now obviously, you have to know why you're doing something.

You can't just say, "Well, I want to do something with encryption and do that."

You have to know what this command is for or why you're doing it

but you always have a question mark or a next button to walk you through it.

Now, also right along with this is the tab key.

Now I mentioned that the tab key can kind of repaint what you're typing

if you ever get interrupted by those messages, which is true,

but it will also finish any partially typed command.

So let's just look at this.

I see-- I see two commands that start with D. Actually I forgot to show you something.

I can type in D question mark.

Notice no space at all and the IOS is like, "Oh, you just want to know what command start

with D," and it will filter down to just those two.

Now I'm going to hit the tab key, watch this.

What just happened there?

It just said, okay, he hit tab which--

which really means finish the command that I've started typing.

But now the Cisco IOS is saying, "Well, both of my D-Command start with DIS, so I can finish it

that far but now I don't know which direction you want to go.

Do you want to disable or do you want to disconnect?"

So, as soon as I type in that fourth character, let's say I put a C there,

it now knows I want to disconnect.

So I can hit the tab key and it finishes that command.

You will start seeing people that have a lot of experience in Cisco

that that tab key is like their best friend.

They're just constantly, you know, they're-- I'm just going to type a few things real quick,

you know, copy, running config to start up config--

I mean it just becomes like second nature to you in the commands that you're doing

to just say, okay, let me hit that tab key.

Now-- now let me also mention this.

Ignore the commands I'm typing, I'm just kind of showing you how to work with this here.

I'm going to do a disable, take me back to that user mode.

What was I going to say?

The tab key is also optional.

So let's say I want to-- well, let me get-- let me get back here.

I want to disable, right?

Well I know, you know, I'm going to type in DIS which it's still saying, okay, wait a sec.

There're still two commands I don't know, but now as soon as I type in A,

does it know which command I want to use?

Yeah, it does because disconnect doesn't have an A there.

So, if I just hit the enter key there, it executes that command.

Okay, rule across all Cisco IOS.

You can use a shortcut of any command as long as you type enough characters

for it to be uniquely recognized.

Okay, so for example one of the big commands you will always type is enable.

Enable is actually the command.

Where's my pen?

Enable is the command that allows you to move from user mode up to privileged mode.

That's one of the first commands that we're going to discuss.

You will find almost-- hardly anybody actually types in the enable command.

Almost everybody will just get in, they will go EN because that's the shortest version of enable

that they can type and still allowed to be valid.

Or, you know, disable is actually a command that's rarely used

but disable moves you back to user mode.

It's kind of like why would I ever want to deescalate my privileges?

I want to always escalate, you know.

Anyway, well, maybe you do.

Well, you know, what if you don't want to leave it logged in?

Well, most people will just type in exit, you know, and drop back out.

So they're now back in the-- back in that mode.

So, any command can be shortcutted that way, okay.

So, now let's talk about the modes themselves.

Knowing the modes of your Cisco devices is almost as important

as knowing the commands themselves.

Actually, let me change this thing and I'm going to revise my statement right there.

Knowing the modes of your Cisco device is more important than knowing what commands

to type themselves, that's a bold statement.

Think of it this way.

Have you ever-- you guys remember the game Myst?

Oh, I despise that game.

It was when computer graphics where it's first starting to get really good and essentially

with Myst, you would be put in all these different puzzle scenarios like you would walk

into a room and you know in this room, all these different gadgets do things like if I click

on that part of the screen which you know spins the little timer and then I click

on the notebook to open it up and look inside of the notebook, then I'm going to find the piece

of paper that only appears if the timer is spinning.

Where if I chose to do it when the moons were aligned,

I would then progress to the next level of Myst.

It was one of those kinds of games where you just spend hours staring

at the same screen trying to figure out what area of the screen to click

on at what time to make something happen.

Well, in the same way, think of these modes of the Cisco IOS like the areas of the screen.

When I'm in user mode, I have a certain set of commands that I can type

in that-- and you saw them matter of fact.

When you first get into switch, this little right angle bracket right there lets you know

I'm in user mode and I hit the question mark and, okay, you get a feel that that's it

by the way, that's all the commands you can type in.

Oh, actually sometimes-- forgive me,

sometimes I've been doing this long enough that I assume things.

When you see a more, you can either scroll line by line by pressing the enter key like that

or you can scroll a page at a time by pressing the spacebar

which in this case scrolls the rest of the way.

Now if you see a more, the enter key

and the spacebar is the only ones that kind of move you around.

If you press any other key like sometimes I'm like, okay, I've seen enough,

I'll hit the Q key, it just stops the output right there.

Now, I hit Q but I could also go in and hit M or any key except space

or the enter key will stop that up.

Okay, so you get the feel, right?

These are all the commands that are in user mode.

Now, as soon as I type in enable, I'm now moved into a privilege mode.

I know I am because I'm looking at that pound symbol on my device.

That tells me I'm in privilege mode which says I now have access

to all the functionality of this device.

There're no restrictions on what I can do anymore, I'm now escalated.

Now, you might say well, what is-- you want a password protect that?

Well, absolutely, but this is a device with no configuration

so there is no password yet, right?

So now watch what happens.

I hit the question mark and I go, okay, well there's some and hit the spacebar.

Good grief, and there's some more and--

I mean, wow, can you see the difference between user mode and privileged mode?

Again, going back to that Myst, it's like one mode I'm in a room

with a couple little buttons that I can push and look around.

In another room in Myst, I'm in this gigantic galaxy where anything is possible

and remembering that each one of these things, you know, when I type in show

and hit the question mark, each one of these has a whole giant subset of commands that could go

in there and each one of those to have a whole giant subset.

Again like I type in show IP and you know hit the question mark,

it's like good grief, you know.

And like each time you do that, it's like walking into a new room with Myst where you have

to kind of figure out what to do.

But the point is, the reason I said knowing what mode to be in is more valuable

than knowing what command to type is because given enough time, you can kind of poke

around in the mode and kind of be like oh, okay, I see.

If I do this and this and, you know, as long as you're in the right mode

to start off with, okay, that makes sense, okay.

Now don't let-- when you see that gargantuous amount of commands, don't--

again, don't let that scare you away.

In your Cisco career, you will always only know a subset of commands that there are--

like I said, there're millions of combinations of commands in the Cisco IOS.

There are some core commands that will get you going and then there's some peripheral commands

that those are the ones that reference books are made for, you know,

you'll look them up when you need them.

So, two modes that we've talked about so far.

User mode allows limited visibility of the IOS.

You know I can do some-- this is meant for a help desk technician to come in there

and say "Oh, look it's running," or "Oh, look I can ping it from this device."

And that must mean that it's working or, "Ooh,

I can't ping it from this device, so it must not be."

Once you move to privileged mode, now you have full options.

This is where the admin, a true Cisco admin is engaged.

Now in the privileged mode itself, you know, we're sitting here from that pound symbol,

there's a lot of stuff that you can do.

I mean, there's a lot.

But from this-- from this mode itself, you can't really configure anything.

This is all, you know, kind of working with the IOS like you can do some ping commands you know

and go that way or you could go, you know, do some show commands,

do a show running configuration and see, well, here's how my device is configured and I can--

you know, you can kind of go through and get a lot of information from the switch,

get all the information from the switch but you can't change anything.

To change something, I have to start moving into the configuration mode.

The configuration mode always starts with global, meaning I move from user to privileged,

from privileged to global and then I can either do some config there or move into one

of the hundreds of subconfiguration modes that I have.

So let me give you an example.

I type in, and here's the command by the way.

To move in the global configuration mode, I type in configure terminal.

In a nutshell that means I am configuring my device from the terminal,

you know, that's why I'm doing that.

You can configure that device from all kinds of sources.

I can copy configurations from other places or do it remotely, you know, all that [inaudible]

but I am configuring it from my terminal.

That's the most common place that you configure it from.

Now I've just moved, and you can see the prompt changed to config.

I am now sitting in global configuration mode.

Things that I change here are global to the whole device.

I mean things like the name of the device, like I can type in host name,

you know this is a global option.

And by the way I'm just-- this nugget, I'm just about the modes, I'm not about the commands.

I'm just using these commands to demonstrate the mode, so I can type in host name Jeremy needs

to cough [laughs] and I'll be pausing shortly to do that and you--

oh, man, I even went beyond that.

So, Jeremy needs to cough now becomes the name of this device.

It's a global change that affects the whole thing.

Or for example, sending a password to protect this transition, setting a password

to keep people from going from user mode to privileged mode just

by typing in a command is a global change.

So all of those kind of things, and there's a lot

of them can be done from global configuration mode.

But then from there, and I noticed this is where I brought this little cheat sheet in here,

I can move into any one of the subconfiguration modes.

So for example, this device, this switch has a whole bunch of interfaces.

Hang with me for a second, I will show you.

And actually I'm going to-- I want to show you something-- oh, perfect, perfect.

So, I've got this pound symbol, right?

And now my cursor is blinking here, so I'm going to do a show--

whoa, wait a sec, that doesn't feel right.

You know, I'm typing my show command right here but it's at the end of a status message.

What do I do?

Tab key, right?

Tab. Moves me down to the next line, gives me a good prompt again and now I'm typing my command.

Okay, so I'm going to do a show IP interface brief.

By the way, that's my all time favorite command in all of Cisco, and I'm able to see all

of the interfaces that this device has.

Now-- and I'm going to stop saying this, but we will discuss all of that.

You know, what does this mean, what's the zero slash whatever, you know,

all of that to be discussed, just talking about modes right now.

But let's just say I wanted to configure just that interface.

That interface connects to a key server and I want to make sure

that it's working the right way or whatever the case may be.

So okay, I want to set up that interface, here's what I do.

I'm going to go into global config, so I'll type in config T. And by the way,

let me just show you that again, I can type in cough.

Oh, I'm so-- I'm so into the tab key I just hit it naturally.

Cough T and that will do the same thing, that's a nice shortcut to do there.

And then I can say, well, I actually want-- I don't want to do anything global to this device.

I want to just do that one interface, so I'll type in interface FastEthernet0/1 and hit enter.

Notice every single time I'm doing this, my prompt is changing.

Let's say okay-- okay, you've now moved from kind of global--

there's a global sense configuration mode into an interface.

So now all the commands that you type, you've entered another room in that Myst video game,

all the commands that you type affect just that interface.

So you'll see commands like I want to set the speed of that interface to 100 or I want

to set the duplex of that interface to full duplex, you know,

and I can start doing my interface configurations from here

but everything always affects this.

Now look back at this chart.

Notice that once I'm in the interface configuration mode,

I can always move back to global.

Well, how do I do that?

I got exit, so I can be in the interface configuration mode, type in exit and bam,

I'm back out to the global configuration mode.

Now here is the key.

Remember, this is like the different rooms of Myst.

The little widget, the timer that you spun under the interface isn't going to work

from global for-- so for example, I type in speed and hit the question mark--

not that key, I hit speed and hit question mark and it's going--

I don't know what you're talking about.

Sorry, total invalid command.

Well, wait, wait a sec, what about duplex?

Duplex question mark-- nope, sorry totally wrong command.

Ooh, do you see why?

I said knowing the modes is more valuable because you can kind of reason your way

through it if you know what mode to be in but if you're in global,

you won't even get the commands that you need for that individual interface.

So, the commands that are in the interface don't work in global and the commands for instance

when I typed in-- remember back here, yeah, let me back up.

I typed in show IP interface brief, I was in privileged mode.

So the commands that I type from privileged mode, if I type in show IP interface brief,

it's like oh I'm sorry, you're off now.

Now notice even this, Cisco is trying to guide me, it's going, "Hey, you went off right here."

It says invalid input detected here and you're going, well, why,

that's how you spell show, I mean it seems right.

Well, what it's saying is in global configuration mode,

there's no commands that start with anything SHO.

If I hit S question mark, you notice there's a whole bunch of commands but there's only--

I can see-- let's see, I'm looking for SH, there right there, shutdown.

So I have this shutdown which is it's saying, okay, that was valid, but as soon as you went

into the O in global configuration mode, I don't have any commands that start with SHO.

Now, if I go into the interface, interface 0/1 and type in S question mark,

notice totally different set of commands than what I had in global configuration mode.

Are you seeing it?

Are you seeing-- are you seeing the mode?

Now that is just two of the modes, that's global and that's interface config but literally,

you know, we've got line config, router config and this is just-- these are just examples,

this goes on to the hundreds of modes.

Each one dedicated to configuring some aspect of your Cisco device.

Now, last thing I want to show you here is-- notice I was sitting in these modes.

I can type in exit to move back one level at a time, you know,

I got to-- it's getting just ugly.

I can type in exit and move back one level at a time, so let me go back here.

I'm in interface config, I can exit to global, exit back to privileged and then exit

out completely and now I'm back-- back in user mode.

I'm going to type in enable, go back into global, go under FastEthernet0/1.

I can also do what I would call a bailout.

You can do it one of two ways.

I can type in end and notice I'm dropped--

I'd skipped right past global and go all the way back to configuration mode or privileged mode,

all the way back to the base, or I can be in interface FastEthernet0/1

and hit control Z, and that will also bail me out.

Now I actually like control Z better because no matter where I'm at, I could be in the middle

of typing a command, I could be in interface FastEthernet0/1 and type in--

well, the description of this interface is connection to--

and I'm like I don't even want to be here, control Z, bam.

It's like you're done at any point, whereas if I would type in end,

it would think that's my description.

So control Z is the ultimate, at any point, you bail out kind of command.

So there it is, that's the welcome to the world of Cisco.

Like I said, if this were Windows, this would have been like, okay, that's the start button,

that's the control panel, you know.

We aren't really saying what the control panel does or what the start button is for

but you kind of get the idea of just how to move around and navigate.

So here's what I want you to do with this.

I would like you-- before you dive into the next nugget, if you can, well,

if you have some lab equipment, just any Cisco device will do, get in there,

start navigating into user mode, into privileged mode, into global config.

Start seeing what other modes there are.

Like for instance, you saw on that graphic there was line mode or router mode.

You might look at that and say, well, what are those?

You know, start gaining a little curiosity of like what are some

of the things that I can do from these modes?

Don't worry if it's lab equipment, now don't do it on production,

but if it's lab equipment, you can't hurt anything.

You can just simply reboot the device and it erases everything

that you did back to the beginning.

So get that familiar and play around with that and then dive into the next nugget

where we're going to start getting into the configuration of the switch itself.

For now I hope this has been informative for you and I'd like to thank you for viewing.