WEBVTT

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 Hello, this video is part of the CCT
 routing and switching series and

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 in this video I'm going to give you an
 introduction to Cisco iOS and another

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 form of an operating system called CATOS,
 both of which are software operating

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 systems you will find in Cisco
 routers and switches.

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 My name is Keith Bogart and I will be
 your instructor for this session.

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 So let's talk a little bit about
 the objectives for this session.

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 So if you're looking at the CCT blueprint
 for routing and switching this

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 covers three different categories all
 under section two, namely describing

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 the different operating modes for Cisco
 iOS and CATOS software, navigating

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 between the different operating modes
 that are listed as well as determining

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 the current mode of the device.

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 So let's start with Cisco iOS, instead
 of most likely the Cisco software

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 that you're going to run
 into on a daily basis.

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 So iOS stands for the internet working
 operating system, that's what the

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 acronym iOS stands for, and it is the
 native software that you will find

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 on the vast majority of Cisco
 routers and switches.

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 I say vast majority because there are
 some corner cases of routers and

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 switches that do run different operating
 systems, but most of them run

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 some variant of iOS.

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 Now you'll hear things called iOS main
 line, iOS XE, iOS XR and all sorts

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 of other stuff. There are some slight
 differences between them, but as

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 far as this session's concerned as far
 as identifying the different modes

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 of iOS, they're basically
 the same.

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 And Cisco develops different iOS
 software for different platforms.

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 So the iOS software that you will find
 for example on an 1841 router looks

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 and feels very, very, very similar to the
 iOS you'll find on another platform

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 like a 7200 series router on a 6500
 series switch, so on and so forth.

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 But there might be some minor differences
 and that's because the way Cisco

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 is structured, it's such a large, such
 a huge company that they have different

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 business units within the company and
 one particular business unit will

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 focus on a certain line
 of routers or switches.

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 Another business unit will focus on a
 different line of routers or switches

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 and although they both start from a common
 software platform of iOS, their

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 code might be slightly different
 from one another.

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 So features and the way you configure
 those features on one router switch

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 might be a tiny bit different on a
 different model of router switch.

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 However, for your purposes as a field
 service engineer whose primary job

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 is to go out, identify the device or
 the chassis or the interface that's

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 having problems and we've already seen
 that in some of the previous videos

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 and then issue some basic iOS commands
 just to get in so you can, for

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 example, collect the running config
 or collect some diagnostics.

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 Those differences between the different
 iOS platforms aren't really going

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 to be relevant to you.

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 And Cisco iOS is usually operated through
 the command line interface.

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 Now there are ways to get into a router
 switch using a graphical user

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 interface accessible
 via a browser.

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 However, the graphical user interfaces
 mostly are pretty limited, especially

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 when it comes to diagnosing and troubleshooting
 problems on a router switch.

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 So you really do need to expect how
 to know how to use the command line

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 interface and issue the
 correct commands.

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 So with that being said, let's talk
 about the different modes of Cisco

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 iOS. So Cisco iOS has a command hierarchy
 where certain commands can only

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 be done from within certain modes and
 you need to be familiar with what

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 those modes are, the technical name
 or term of those modes and how you

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 go back and forth between
 those modes.

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 So let's start with the top one.

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 We see here at the top when you have
 the name of the device, which might

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 be router, switch, building three
 router, whatever it happens to be.

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 After that, if you see the greater
 than symbol, that means that you're

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 what's called user mode or
 sometimes called exec mode.

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 Now from this mode, you can issue some
 basic diagnostic and troubleshooting

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 commands that begin
 with the word show.

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 For example, let me get into
 a router right here.

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 So here you see a router, I'll make
 this a little bit larger for you.

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 Right now I am at user exec mode, as
 you can see from the fact that I've

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 got a greater than sign.

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 Now with Cisco iOS, it does have a command
 line help built into it, which

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 is by using the question mark.

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 So when you're at any given mode like
 this, if you simply issue the question

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 mark, it will show you all the commands
 are available to you at that mode.

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 And you'll have to hit the space bar
 if those commands occupy more than

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 a single screen.

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 So you can see there are quite
 a few commands right here.

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 But the primary commands that you would
 do from this mode would be commands

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 that begin with the word show, which
 means you want to view the contents

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 of a table, you want to view the contents
 of or what's happening with

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 something. So show commands will
 show you basic diagnostic stuff.

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 You can see there's a lot of other
 stuff here as well at this level.

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 But generally speaking, when people
 get into a router switch, they don't

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 stay in this mode.

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 This mode is very limited
 in what you can do.

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 One of the main commands that's missing
 from here is the configure command.

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 There's no way to change the operating
 characteristics of this device

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 from this mode. So people usually just
 stay in this mode for about one

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 second before they move
 on to the next mode.

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 So what is the next mode called?

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 We can see here the next mode
 is called privileged exec.

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 Sometimes people also
 call that enable mode.

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 You'll probably hear it called enable
 mode because that's a little bit

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 easier to say than privileged
 exec mode.

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 But it means the same thing.

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 And that's evidenced
 by the pound symbol.

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 So how do you get from user
 exec to privileged exec?

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 Well, it's simply just by typing
 one command, the command enable.

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 Or you can just shorten
 that to EN.

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 Another nice thing about Cisco iOS
 is some of the commands are fairly

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 long. And Cisco iOS has a feature built
 into it that if you type in just

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 enough characters where Cisco iOS can recognize
 it as being a unique command,

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 you don't have to
 type in the rest.

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 For example, if I just type in the letter
 E, it's going to say ambiguous.

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 Why is that? Well, if I type E followed
 by a question mark, it'll show

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 me all the commands that
 begin with the letter E.

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 And you can see there's
 four commands.

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 That's why it was ambiguous.

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 It didn't know which of those
 four I want to use.

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 But if I just type in EN, well, now
 there's only one command that starts

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 with EN, enable.

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 So I don't have to type
 in the rest of enable.

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 That's enough. And if I hit the enter
 key, now puts me into privileged

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 exec mode. Now from this mode, once
 again, if I use the question mark,

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 I can see all the different
 options available.

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 And you'll see there's actually several
 more pages of output available

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 at privileged exec mode.

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 So if you're doing monitoring or troubleshooting
 of your device, you're

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 going to want to be in
 privileged exec mode.

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 The show commands you have available to
 you, there's a lot more show commands.

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 And one subset of commands that's only
 available here are debugging commands.

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 If I scroll up to the top, you'll see
 here there are commands that begin

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 with debug. Debugging commands are not
 available in any other mode, but

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 right here. Now from this mode, this
 is good for viewing things on the

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 router or the switch, seeing what's going
 on, troubleshooting or debugging

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 what's going on.

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 But from this mode, you can't really
 change the operating characteristics

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 of the router or the switch.

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 You can't turn on a feature, you can't
 add or change an IP address, you

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 can't change the device
 in any way.

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 So for that, we need to go into the
 next mode, which is called global

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 configuration mode.

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 And you can see that's evidenced by
 the name, well this is called the

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 host name, the host name of the device,
 which in this case is router,

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 followed by the word config
 in parentheses.

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 So, I cannot go directly from user mode
 to config mode, I have to go in

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 this hierarchy, the hierarchy starts
 with user mode, then I have to type

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 enable to go into privilege exec, then
 I have to type in another command

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 to get me into global
 configuration mode.

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 And that command is configure
 terminal, configure terminal.

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 Now, like with anything else, I don't
 have to type in all of that, I just

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 have to type in enough unique
 characters for it to know.

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 So for example, if I type C question mark,
 if I type C O N F, that's enough

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 for it to know that I want
 to do configure, C O N F.

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 And if I do T N question mark, well
 you can see the only thing that, the

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 only keyword after configure that
 starts with a T is terminal.

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 So you can actually type, this is what
 most people type, conf T enter,

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 and that puts me into global
 configuration mode.

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 Of course, you're certainly welcome to
 type out the entire thing, configure

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 terminal, but this will save you, you
 know, one quarter of a second by

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 typing in conf T.

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 Now we're not done yet.

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 Once you get into global configuration
 mode, that is the first mode in

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 which you can configure or change some
 characteristics of your router

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 or your switch. But there are
 sub modes beneath that.

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 For example, if you want to change
 the characteristics of a particular

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 port or interface on your router or
 your switch, for example, you want

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 to add an IP address to
 a router's interface.

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 You want to change the speed
 or duplex of a port.

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 You want to put some sort of security
 feature on an interface or on a

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 port. Well then you have to actually
 go into another sub mode of this,

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 which will put you into that interface,
 and you can see here, that's called

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 interface configuration mode.

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 Doesn't need by the config-if.

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 Now the router or the switch,
 it can't read your mind.

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 If in your head you're thinking, oh,
 I want to go into interface fast

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 ethernet zero slash one, and that's
 where I want to do something.

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 I want to put an IP
 address on there.

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 Well, it doesn't know.

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 Now there's certain other platforms
 out there, non-Sisco stuff, where

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 you could do everything
 from right here.

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 I'm sure there's some routers out there
 that are not made by Cisco, where

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 you could type something like interface,
 fast ethernet zero slash one,

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 IP address, and then put
 your IP address on it.

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 And you could do it all from global
 configuration mode, but Cisco iOS

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 is not like that.

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 Cisco iOS has several
 subcategories.

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 So from here, we have to first type
 in the interface that we want to go

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 into. And I'll type in the whole thing,
 interface, fast ethernet zero

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 slash one. Of course, I could have just
 shortened that to FA zero slash

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 one. And now when I hit enter, now it puts
 me into config dash if or interface

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 configuration mode.

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 So from here, if I use a question mark,
 it'll show me all the commands

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 I can do to that particular
 interface.

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 So all these commands that you see
 right here are commands that would

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 apply specifically to that port
 or interface on this router.

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 Now, what happens if I try typing in
 a command while in this mode that's

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 actually applicable
 for another mode?

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 For example, right now this router has
 a very generic name called router.

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 What if I want to change the name to
 something like building one router?

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 Well, that would be the
 host name command.

0:12:25.780000 --> 0:12:31.860000
 Now the host name command is
 not done from this level.

0:12:31.860000 --> 0:12:35.440000
 The host name command is sort of changing
 the characteristics of the chassis

0:12:35.440000 --> 0:12:39.780000
 itself. It's not affecting
 just this one interface.

0:12:39.780000 --> 0:12:43.700000
 So this command is being
 done at the wrong mode.

0:12:43.700000 --> 0:12:45.520000
 Now one of two things can happen.

0:12:45.520000 --> 0:12:49.880000
 Sometimes when you do a command like this
 at the wrong mode, you'll actually

0:12:49.880000 --> 0:12:51.620000
 just get an error message back.

0:12:51.620000 --> 0:12:55.880000
 iOS is smart enough to know, hey,
 that command can't be done here.

0:12:55.880000 --> 0:12:59.840000
 Other times when you do this command,
 iOS is smart enough to know, oh,

0:12:59.840000 --> 0:13:03.740000
 that is a valid command just not
 from this mode right here.

0:13:03.740000 --> 0:13:06.240000
 It'll kick you out to
 the correct mode.

0:13:06.240000 --> 0:13:07.780000
 So let's see what happens here.

0:13:07.780000 --> 0:13:10.260000
 See, look at that.

0:13:10.260000 --> 0:13:15.980000
 So it did change the name as well
 as putting me at the correct mode.

0:13:15.980000 --> 0:13:19.380000
 This is where I should have been, global
 configuration mode, to change

0:13:19.380000 --> 0:13:21.520000
 the name of the device.

0:13:21.520000 --> 0:13:27.340000
 And there are other
 sub-modes as well.

0:13:27.340000 --> 0:13:30.380000
 Here's one that's called router
 configuration mode.

0:13:30.380000 --> 0:13:35.540000
 If I want to configure some routing
 protocol like EIGRP or OSPF, or I

0:13:35.540000 --> 0:13:40.440000
 want to modify the characteristics of
 an existing running routing protocol,

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 well then I have to get into
 the routing protocol.

0:13:43.580000 --> 0:13:47.500000
 So from global configuration mode, or
 even from interface configuration

0:13:47.500000 --> 0:13:50.660000
 mode, I would type
 router, whatever.

0:13:50.660000 --> 0:13:54.580000
 For example, router rip.

0:13:54.580000 --> 0:13:57.820000
 And now that puts me
 into config-router.

0:13:57.820000 --> 0:14:02.340000
 So now at this point, if I use a question
 mark, it'll show me all of the

0:14:02.340000 --> 0:14:06.420000
 rip commands I have available
 to me within this mode.

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 These are all commands that apply
 to the rip routing protocol.

0:14:10.280000 --> 0:14:16.400000
 If I had done router OSPF, it still
 would have shown me config-router,

0:14:16.400000 --> 0:14:19.820000
 but now it would know, okay,
 he wants to configure OSPF.

0:14:19.820000 --> 0:14:26.420000
 And if I did the question mark, it would
 have shown me OSPF related commands.

0:14:26.420000 --> 0:14:30.100000
 Now, how do I get out
 of these modes?

0:14:30.100000 --> 0:14:34.420000
 We've seen how I can get deeper and
 deeper and deeper, enable, config

0:14:34.420000 --> 0:14:40.240000
-t, router rip, but what if I want
 to move backwards certain levels?

0:14:40.240000 --> 0:14:46.240000
 Well, if you want to move back just
 one level up, for example, I'm in

0:14:46.240000 --> 0:14:48.400000
 router configuration
 mode from here.

0:14:48.400000 --> 0:14:51.500000
 What's one level up in the
 hierarchy of commands?

0:14:51.500000 --> 0:14:54.800000
 What's the level just
 before this level?

0:14:54.800000 --> 0:14:58.940000
 Well, hopefully you said global
 configuration mode.

0:14:58.940000 --> 0:15:02.400000
 So how would I get back to global
 configuration mode from here?

0:15:02.400000 --> 0:15:04.700000
 I can just type exit.

0:15:04.700000 --> 0:15:10.220000
 So whenever you type exit, it will put
 you one level back, one level up,

0:15:10.220000 --> 0:15:14.980000
 in the hierarchical chain
 of Cisco iOS commands.

0:15:14.980000 --> 0:15:19.220000
 If I type exit right now, what mode
 do you think it will take me back

0:15:19.220000 --> 0:15:24.220000
 to? Well, hopefully you said enable
 mode or privileged exec.

0:15:24.220000 --> 0:15:28.540000
 That's right, it'll take me out of my
 configuration entirely and put me

0:15:28.540000 --> 0:15:30.620000
 into privileged exec mode.

0:15:30.620000 --> 0:15:33.320000
 Now, let me show you
 something else.

0:15:33.320000 --> 0:15:39.120000
 Let's say I'm two or three or even
 four levels deep, and I want to go

0:15:39.120000 --> 0:15:42.780000
 all the way back to privileged
 exec mode.

0:15:42.780000 --> 0:15:46.400000
 In other words, right now, if I want
 to go back to privileged exec mode

0:15:46.400000 --> 0:15:51.140000
 using the exit command, I would
 have to type exit twice.

0:15:51.140000 --> 0:15:56.400000
 Once to get back to global config and a
 second time to get back to privileged

0:15:56.400000 --> 0:15:58.120000
 exec or enable mode.

0:15:58.120000 --> 0:16:02.120000
 If you want to get out of your configuration
 modes altogether, no matter

0:16:02.120000 --> 0:16:06.360000
 how deep you are, and go all the way
 back to privileged exec mode, there's

0:16:06.360000 --> 0:16:07.900000
 actually two ways you can do it.

0:16:07.900000 --> 0:16:10.800000
 It's just entirely your
 own personal preference.

0:16:10.800000 --> 0:16:14.960000
 One way is to type
 the command end.

0:16:14.960000 --> 0:16:20.160000
 So notice end gets you completely out
 saying, I'm done, I'm finished,

0:16:20.160000 --> 0:16:23.800000
 configuring, and my configuration.


0:16:23.800000 --> 0:16:28.560000
 Another way that you could do it, if you're
 a big fan of keyboard shortcuts,

0:16:28.560000 --> 0:16:32.220000
 is on your keyboard, you
 could hit control Z.

0:16:32.220000 --> 0:16:36.400000
 Control Z does the exact same
 thing as the word end.

0:16:36.400000 --> 0:16:39.100000
 It gets you all the way out.

0:16:39.100000 --> 0:16:42.840000
 So now hopefully you have an idea as
 far as what the modes are within

0:16:42.840000 --> 0:16:46.680000
 Cisco iOS. Just a couple of additional
 ones I'll show you that are not

0:16:46.680000 --> 0:16:52.180000
 on the slides. I'm not going to explain
 this command right here, I'll

0:16:52.180000 --> 0:16:55.140000
 talk about that in
 a subsequent video.

0:16:55.140000 --> 0:17:03.900000
 But another one you might
 see frequently is this.

0:17:03.900000 --> 0:17:09.260000
 Interface 0 1 slash 0 dot
 101 point to point.

0:17:09.260000 --> 0:17:10.900000
 Okay, so notice this one.

0:17:10.900000 --> 0:17:13.660000
 Config dash sub if.

0:17:13.660000 --> 0:17:17.700000
 This is called sub interface
 configuration mode.

0:17:17.700000 --> 0:17:21.600000
 This is when I'm taking a physical interface
 and I'm telling the software,

0:17:21.600000 --> 0:17:27.740000
 hey, I want you to, in your mind, logically,
 carve this out into sub interfaces.

0:17:27.740000 --> 0:17:31.200000
 In other words, even though this one
 physical interface is connected to

0:17:31.200000 --> 0:17:38.180000
 one cable, I actually want to control
 multiple networks on this one physical

0:17:38.180000 --> 0:17:43.520000
 interface. Well, the control multiple
 networks like multiple subnets or

0:17:43.520000 --> 0:17:49.420000
 multiple layer two PVCs, I have to
 carve it up into sub interfaces.

0:17:49.420000 --> 0:17:53.580000
 And so once I create a sub interface,
 it puts me in a config dash sub

0:17:53.580000 --> 0:17:57.280000
 if mode. That's another one
 you might see frequently.

0:17:57.280000 --> 0:18:01.740000
 All right, so that does it for understanding
 the modes of Cisco iOS and

0:18:01.740000 --> 0:18:05.700000
 how to get into the modes and how to
 go back and forth between the modes.

0:18:05.700000 --> 0:18:10.300000
 Let's go into another form of operating
 system that Cisco has that you

0:18:10.300000 --> 0:18:13.140000
 probably won't see, but you might.


0:18:13.140000 --> 0:18:16.780000
 And it is on the CCT exam, so
 we have to cover it here.

0:18:16.780000 --> 0:18:20.500000
 And that's called cat op cat OS.

0:18:20.500000 --> 0:18:23.820000
 So historically, I have to take you
 back in time here a little bit way

0:18:23.820000 --> 0:18:30.360000
 back in 1993, Cisco had its first acquisition
 of a company which was called

0:18:30.360000 --> 0:18:33.700000
 Crescendo Communications.

0:18:33.700000 --> 0:18:37.640000
 And what Crescendo brought to the company,
 why they bought this company

0:18:37.640000 --> 0:18:42.560000
 is because Crescendo had a very popular
 line of switches of modular switches

0:18:42.560000 --> 0:18:45.500000
 called the Calus 5000
 series of switches.

0:18:45.500000 --> 0:18:50.160000
 So when Cisco purchased Crescendo, they
 purchased a land switching company

0:18:50.160000 --> 0:18:54.900000
 and those switches had their own operating
 system called the catalyst

0:18:54.900000 --> 0:18:57.320000
 operating system.

0:18:57.320000 --> 0:19:02.340000
 And so we frequently shorten that
 to cat OS, the catalyst OS.

0:19:02.340000 --> 0:19:08.900000
 Now, does Cisco still to this day
 make devices that run cat OS?

0:19:08.900000 --> 0:19:11.060000
 The answer is no.

0:19:11.060000 --> 0:19:16.880000
 So they stopped selling switches that
 natively ran cat OS probably back

0:19:16.880000 --> 0:19:19.420000
 in about 2010 or 2011.

0:19:19.420000 --> 0:19:23.920000
 And then the end of
 support was 2013.

0:19:23.920000 --> 0:19:28.300000
 End of support, what that means is if
 you open a case with the Cisco TAC

0:19:28.300000 --> 0:19:33.160000
 and they discover that the device you're
 on is running cat OS, technically

0:19:33.160000 --> 0:19:34.740000
 they can deny you service.

0:19:34.740000 --> 0:19:38.960000
 They can say, look, we not only stopped
 selling that software a long time

0:19:38.960000 --> 0:19:42.080000
 ago, we don't even
 support it anymore.

0:19:42.080000 --> 0:19:45.580000
 It's sort of like if you go to Microsoft,
 when Microsoft you say, hey,

0:19:45.580000 --> 0:19:53.200000
 I've got a Windows 3 device or something
 way before even Windows 95.

0:19:53.200000 --> 0:19:56.000000
 They'll probably, Microsoft will probably
 tell you we can't support that.

0:19:56.000000 --> 0:19:59.520000
 It's too old. Our support stat
 doesn't even know it anymore.

0:19:59.520000 --> 0:20:01.640000
 So why is it in here?

0:20:01.640000 --> 0:20:07.060000
 Well, because lots of switches that
 Cisco sold used to run the cat OS

0:20:07.060000 --> 0:20:08.500000
 operating system.

0:20:08.500000 --> 0:20:11.520000
 And some of them are still
 out there to this day.

0:20:11.520000 --> 0:20:15.260000
 Some people have not upgraded their
 switches in the last seven or eight

0:20:15.260000 --> 0:20:17.000000
 years because they're doing fine.

0:20:17.000000 --> 0:20:18.160000
 They're doing the job.

0:20:18.160000 --> 0:20:21.300000
 They don't need the enhanced features
 and those switches are working just

0:20:21.300000 --> 0:20:26.660000
 great. And yet the running
 cat OS operating system.

0:20:26.660000 --> 0:20:30.120000
 So if you run across one of those switches
 and you get into it, you'll

0:20:30.120000 --> 0:20:34.200000
 recognize very, very quickly, oh, this
 command line does not look like

0:20:34.200000 --> 0:20:36.300000
 iOS. What is this?

0:20:36.300000 --> 0:20:39.760000
 Well, it's probably the
 cat OS operating system.

0:20:39.760000 --> 0:20:44.520000
 Now the cat OS operating system in
 I own personal opinion was actually

0:20:44.520000 --> 0:20:49.860000
 a lot easier than Cisco iOS because
 it didn't have all these multiple

0:20:49.860000 --> 0:20:53.400000
 modes and sub modes and
 sub modes of sub modes.

0:20:53.400000 --> 0:20:57.900000
 Cat OS really just had two
 modes and that was it.

0:20:57.900000 --> 0:21:01.560000
 There were some also comparisons
 to it that I personally liked.

0:21:01.560000 --> 0:21:06.220000
 For example, cat OS only had
 two modes, exec and enable.

0:21:06.220000 --> 0:21:10.080000
 That was it. So when you got initially
 into the switch, you would have

0:21:10.080000 --> 0:21:13.600000
 the name of the switch like building
 one switch and then it might say

0:21:13.600000 --> 0:21:16.440000
 like console in parentheses.

0:21:16.440000 --> 0:21:20.620000
 And then you typed enable just
 like you do in Cisco switches.

0:21:20.620000 --> 0:21:22.200000
 Then you were in enable mode.

0:21:22.200000 --> 0:21:24.300000
 At that point, you were done.

0:21:24.300000 --> 0:21:25.800000
 Those were the only two modes.

0:21:25.800000 --> 0:21:29.340000
 So from that enable mode, you would
 do all of your configuration, your

0:21:29.340000 --> 0:21:31.680000
 troubleshooting, your debugging.

0:21:31.680000 --> 0:21:34.900000
 You didn't have to bounce back and forth
 between all these different modes.

0:21:34.900000 --> 0:21:37.140000
 So it was a lot easier
 to remember that.

0:21:37.140000 --> 0:21:41.940000
 Whereas we know now that was iOS, there
 are multiple modes of operation.

0:21:41.940000 --> 0:21:48.160000
 Another difference in Cisco iOS, Cisco
 iOS devices have two configuration

0:21:48.160000 --> 0:21:52.620000
 files. There's the running
 configuration.

0:21:52.620000 --> 0:21:55.500000
 So when you're actually in the router,
 the switch and it's up and it's

0:21:55.500000 --> 0:21:59.600000
 running and you're making changes, what
 you're making changes is to the

0:21:59.600000 --> 0:22:04.500000
 configuration that's stored in DRAM memory,
 which is the running configuration.

0:22:04.500000 --> 0:22:08.560000
 But as we know from our previous videos,
 DRAM memory when it's powered

0:22:08.560000 --> 0:22:12.180000
 off loses everything inside of it.


0:22:12.180000 --> 0:22:14.760000
 So if you make a whole bunch of changes
 to your running configuration

0:22:14.760000 --> 0:22:18.060000
 and you don't save
 them, they're lost.

0:22:18.060000 --> 0:22:22.680000
 That's because Cisco iOS has a second configuration,
 a long-term configuration

0:22:22.680000 --> 0:22:25.400000
 called the startup configuration.

0:22:25.400000 --> 0:22:29.280000
 And that's stored in non
-volatile RAM or NV RAM.

0:22:29.280000 --> 0:22:31.400000
 So one of the things you have to learn
 when you're dealing with Cisco

0:22:31.400000 --> 0:22:35.960000
 routers and switches is to very frequently
 save the changes from your

0:22:35.960000 --> 0:22:38.620000
 running config to your
 startup config.

0:22:38.620000 --> 0:22:41.360000
 And that's a manual process
 with a manual command.

0:22:41.360000 --> 0:22:43.720000
 Not so with CadoS.

0:22:43.720000 --> 0:22:47.180000
 CadoS did not have the concept
 of two different config files.

0:22:47.180000 --> 0:22:51.240000
 As soon as you hit the enter key, your
 changes were automatically saved.

0:22:51.240000 --> 0:22:53.460000
 So you didn't have to
 worry about that.

0:22:53.460000 --> 0:22:57.640000
 Now in iOS, the commands
 vary widely.

0:22:57.640000 --> 0:23:01.160000
 There's all sorts of syntax
 with the iOS commands.

0:23:01.160000 --> 0:23:06.300000
 In CadoS, vast majority of the commands
 began with the word set.

0:23:06.300000 --> 0:23:10.920000
 Set VLAN, set speed, set
 duplex, set trunk.

0:23:10.920000 --> 0:23:13.420000
 They all began with the word set.

0:23:13.420000 --> 0:23:19.180000
 And in iOS, if you want to undo or erase
 a command you've typed in, you

0:23:19.180000 --> 0:23:21.660000
 would preface that command
 typically with the word no.

0:23:21.660000 --> 0:23:26.140000
 Like no IP address, no router rip.


0:23:26.140000 --> 0:23:28.920000
 Or you could possibly use
 the default command.

0:23:28.920000 --> 0:23:33.700000
 In CadoS, it was the clear command to
 set something back to its defaults.

0:23:33.700000 --> 0:23:39.480000
 So here's an example of some screen
 output of a cat OS switch.

0:23:39.480000 --> 0:23:42.920000
 So here we are in enable mode.

0:23:42.920000 --> 0:23:48.360000
 Show config was similar to the show
 running config command in iOS.

0:23:48.360000 --> 0:23:51.980000
 Set prompt, that changed the
 host name of the switch.

0:23:51.980000 --> 0:23:55.700000
 So instead of host name router one
 on a switch we could have done set

0:23:55.700000 --> 0:23:57.720000
 prompt, switch one.

0:23:57.720000 --> 0:24:03.700000
 The set VLAN command was used to not
 only create a VLAN, like in this

0:24:03.700000 --> 0:24:08.100000
 case we're creating VLAN 2, but in that
 same line, in addition to creating

0:24:08.100000 --> 0:24:11.780000
 the VLAN, we could assign it
 to our ports on our switch.

0:24:11.780000 --> 0:24:15.620000
 Now on Cisco iOS based switches,
 it's a two step process.

0:24:15.620000 --> 0:24:19.600000
 There's one command that could create
 the VLAN, a completely different

0:24:19.600000 --> 0:24:25.600000
 command, done within the interface itself,
 to apply that VLAN to the interface.

0:24:25.600000 --> 0:24:29.320000
 Here in CadoS, it was all one
 command done on one level.

0:24:29.320000 --> 0:24:36.300000
 And here's some port channel commands
 where we're doing ether channels.

0:24:36.300000 --> 0:24:39.900000
 Here's where we're creating a trunk
 and specifying that that trunk is

0:24:39.900000 --> 0:24:44.700000
 using a certain encapsulation type
 of 802.1Q, that it's not using DTP

0:24:44.700000 --> 0:24:51.200000
 negotiation. Here we're creating another
 trunk that's using ISL, that's

0:24:51.200000 --> 0:24:52.140000
 manually static.

0:24:52.140000 --> 0:24:56.740000
 So you can see all of this stuff is
 done beneath one level, the enable

0:24:56.740000 --> 0:25:01.240000
 mode, and pretty much everything
 starts with the word set.

0:25:01.240000 --> 0:25:06.800000
 So that concludes this video on the
 differences between the modes of iOS

0:25:06.800000 --> 0:25:09.480000
 software versus CadoS software.