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>> When I took my CCIE exam, many moons ago.
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You walk into the exam, it's a nerve racking
experience, and you have to actually sit
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with the proctor for about 15 minutes before
your exam starts, where they go over all
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of the rules of the exam, you know, like
when the lunch breaks are, you know,
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no talking, all those kind of things.
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And when you get to the lab itself, and you look
at the book, rule number one of the CCIE is,
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no static routes anywhere at anytime for any
reason unless explicitly spoken of in the lab
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that are you allowed to using things.
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What-- now why would Cisco band
you from using static routes?
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Because you can accomplish anything
using static routing and a lot of time.
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So we're going to start now,
taking the concepts that we saw
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in the previous nuggets of subnetting.
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And start practicalizing
it, if I can make up a word.
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Start identifying these networks,
putting around our organization
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and then moving data between them statically.
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So I'm going to start of by
reviewing the purpose of routing.
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Kind of just again big picture
bring us back to it,
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how static routing can help us
accomplish our goals of routing,
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and then look at some configuration
and design scenarios for static routing
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that actually start doing
it in a live environment.
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If someone were to ask me the
question, Jeremy, what do you do?
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I would respond, and I'd say, "I'm an IT guy.
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That's what I do."
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Now is that a complete answer?
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Well, no, because they could say, "Well,
can you in a screw in a light bulb?"
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And I go, "Well yeah.
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I guess I could do that too."
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And, "Well, can you ride a bike?"
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"Well yeah."
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I mean, sure.
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There's all this little somethings but when
somebody ask big picture, what do you do?
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That's the answer.
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So when you say, what is a router?
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What is routing?
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I mean, there's all kind of
some things that you could do.
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But these are the main answers on the screen.
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Number one is stopping broadcasts.
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Could we live in a world without routers,
meaning, could we just have one big flat network
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that we call the internet where everything is
all, I mean, get rid of the subnet mask, right?
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There's no distinction anymore.
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Everything is just one big,
bleh, you know, one big network.
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That the answer, if there was no concept of
broadcast, then the answer would probably, yeah,
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I mean, there's other considerations.
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But the major constraint is the more
device as you add to the network,
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the more and more broadcast there are,
meaning messages that go to everybody.
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So the worst and worst performance,
it gets to the point
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that would just become unusual,
and our computers need that.
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I mean, they need some kind
of big picture communication.
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They need to be able to talk to everything
on the subnet, to resolve an IP address
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to a MAC address, or to get a DHCP request.
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I mean, there're all kinds
of reasons for broadcast.
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But the number one-- one of the number one
goals of a router is to stop broadcast.
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So when, we have broadcast on this
network right here, they stay there.
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They don't bother anybody else.
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The broadcast in the Arizona stand, Arizona,
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they broadcast in the California
office state in California.
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The second thing a router does is find
the best possible path to does the nation.
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Well, that's its goal; one of its goals.
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Does it always do that successfully?
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No. Why? Well, because there're kinds of
sophisticated mechanisms that go into that.
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I mean if a router, let's say, we have a
router sitting at your house right here, right?
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And that connects to a service router, right?
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And they connect to other service routers
and, they connect to other service routers,
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and you know, that we could have all this
big spider web of all these connections.
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That's what makes the internet so
powerful is everything is connected
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to everything when it get there.
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I saw a picture once on a big post.
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You know, those gig posters
you see in tech companies.
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And it was a map of the connections
on the internet.
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And it was just pretty much just one big solid
blob of everything and they actually have
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to use shading of colors to represent
the different areas of that blob,
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of how money hundreds of connections
were coming out of each site.
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So there're all kinds of different ones.
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So when it comes out to it, this router at
the service router has to say, "Okay, I think,
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to get to Google, it's best to go that way."
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And this one says, well I
think to continue that journey,
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it's best to go that way,
and this way, and this way.
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And, you know, even through all those redundant
pass eventually finds the best way to get
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to google.com, if that's
for somebody ends up going.
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So that's one of our routers jobs.
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And then finally, a routers job is to
move the Unicast Traffic between networks.
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And if you think about it, it's like okay, well,
they stop broadcast and they also stop multicast
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which is a message that goes to a
group of people instead of everybody.
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But they stopped them by default.
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But I mean their goal is not to just saver
network communication, their goal is to say,
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if this happy computer on the left, you know,
192168.1.50 wants to speak to this computer
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over on the right 192168.3.50,
we can make that happen.
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It can come to the router and the router
is like, "Absolutely, I can get you there.
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Let me send you to this guy and
he will get you along the way."
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If I want to directly communicate,
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that's a Unicast with somebody
else, that's what a router can do.
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Well, now we come to our first method of routing
and that is static routing, the manual way.
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Then you might remember when we're
talking earlier, I said, switches,
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when you put on the box, do what switches do.
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They switch.
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And now, you don't get many
benefits until you configure VLANs
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and all the other staff we talked about.
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But a router, when you pull it
out of the box does nothing.
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It has no configuration.
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You have to get involve, so you're there
with the console cable doing what you do.
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So let's say you pull this Cisco
Router out of the box and you go
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into the FastEthernet0/0 interface.
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And you give it the IP address
192.168.1.1/24 or 255.255.255
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or 0 that the router immediately goes, Uh-hmm.
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I am now one network smarter.
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I know how to reach one network
and that is 192.168.1.0.
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Remember the first IP address; you can't
use it because it identifies the network.
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That's what the router is used
as kind of like the network name,
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like I know how to reach that guy, right?
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So you're going in and you say, okay, you
want me to go under the interface Serial0/0
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and I'm going to give it the
IP address 192.168.2.1/24.
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Now notice, I said, you're giving the IP
address 2.1/24, but the router rounds that down,
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it goes, okay, well, if I have 2.1, then I
must be connected to the 192.168.2.0 network.
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I am now one network smarter.
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But there and lies the problem is the router is
only know how to reach their connected networks.
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So I mean, if this computer on the
left wanted to ping something over here
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on the right 192.168, you know, 2.1,
you know, that IP address there,
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it would be able to because it would come to
it's default gateway which is 192.168.1.1.
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Router would say, "Oh, you're
trying to ping 2.1."
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No worries there.
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We can make that happen and it, you
know, its kind default like itself.
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And so it replies back and says, success.
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Now you might be saying, well,
can't it ping 192.168.2.2 as well?
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Sort of. Okay, let's-- I mean
here's what will happen, right?
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That's-- I initially was going to say
that, but then I back off really quick.
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If I said, on this computer, ping 192.168.2.2
which is over here on the other side,
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the ping message would go to the default gateway
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and the router would be like,
"Hey, I can totally get there.
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I know how to get 192.168.2.
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whatever network and I know how to get there."
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So it goes, okay, 2.2, it sends out
[inaudible] message saying, "Hello 2.2.
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I've got a message for you."
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2.2 replies and like, "Great."
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So the message actually comes right here
form 192.168.1, well, I'd give that guy 50.
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1.50 as the source IP address and it goes,
"Hey, I want to talk to you 192.168.2.2."
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The router looks at that
IP address and says, "Well,
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that's great, but I don't know who you are.
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I don't know how to reach."
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So this router over here on the right is
the one that pops over the big question.
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He's like, "I don't know
how to reach 192.169.1.50."
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Matter of fact, I don't know
how to reach 192.168.1.
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anything. I'm looking at my running
table and there's nothing there.
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Now, you and I at this picture and you're
like really, come on, router 2, no.
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I forget to give this guy a name.
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Router 2, its right over there.
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As a matter of fact, you even
saw it come in your interface.
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You saw it come in whatever interface
Serial0/0, don't you know that you have
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to go backout that interface to get there?
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Nope. Routers aren't that smart.
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When you go on to a router and give
it IP addresses, it says, okay,
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I only know for instance
router 1 here on the left says,
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I only know how to reach
192.168.1.0 and 192.168.2.0.
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Router 2 over here on the right
hand side, do I said left, right,
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I think I'm just getting
everything right mixed up here.
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So router 2 on the right hand side says, "I only
know how to reach 192.168.3.0 and 192.168.2.0.
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So I do not know how to reach this, nor
does router 1 know how to reach this."
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Do you see the dilemma?
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We only know how to reach our connected network.
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So static routes allow you to
educate the router to new places.
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What that means is you and I as
Cisco administrators get involve
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to tell theses routers where to go.
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Clear of this gibberish.
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So I as-- if I'm wanting to use static routes,
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I would come to router 1
here on the left hand side.
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And I would say, hey, router 1 to reach
the 192.168.3.0 network which is something
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that you don't know how to reach because
it's not directly connected to you,
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it's directly connected to router
2, but you don't know that.
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So to reach this network, you need
to go to 192.168.1 or sorry, 2.2.
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So essentially, we're using something router
1 knows how to reach to reach something
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that router 1 didn't know
how to previously reach.
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So when router 2, I'm going to
have to come in there and say,
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router 2 for you to reach
192.168.1.0/24 that whole network.
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Now, again, I'm going to identifying the whole
network, every device over here on that network.
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For you to reach that network,
you need to go to 192.168.2.1.
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Now does router 2 know how to get to 2.1?
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Yes, because it's directly
connected to that network.
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It knows how to get to directly connected
nets, however, it does not know how to get
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to the indirectly connected networks.
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Now, you can imagine.
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So to do an environment like this, you know?
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Again, let's make this real.
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Let's say, this is an office in Arizona.
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Over on the right hand side
is an office in Texas.
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We connected a WAN link using some service
provider in the middle and we've got
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that all working now, but we need
to tell, you know, the Texas router,
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here's how to get to Arizona and communicate
to their devices and their IP phones
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and make phone calls and get them
inside to get to their service.
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I mean, so that's the kind of
scenario that we would be in.
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But you can imagine that when
we get to a network the size
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of the internet, that doesn't workout well.
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Where there is literally millions and
millions of networks out on the internet.
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We don't want to sit there one by one and say,
okay, router, to get to the 1.1.2.5 network
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or 2.0 network go to the internet.
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To get to the 1.1.3.0 net, go to the--
I mean, we don't want to do that,
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it would take all day, not all day, all life.
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So what we would do for that is go to
the router connected to the internet
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and use what's called a default route.
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Now I think I did this early in the
series, but if not, this will be the first.
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We actually go into the router and say, to get
to the 0.0.0.0 network, right, go that way.
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I mean the actual route, I mean, when we-- let
me get a little bit more into syntax, right?
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I want to, before we get into the live can fail,
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I'll show you what the actual
command looks like.
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So on router 1, this is actually
in global configuration mode.
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I go in there and so I'll put config.
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This is kind of the prompt were saying.
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This is an IOS simulators, do you know that?
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And I type in IP route, think of that as
like the, I want a route command, IP route.
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I want to get to the 192.168.1.-- or
scratch that, we know how to get there.
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3.0 network with the subnet mask, it be so
nice if we could type /24, but we can't.
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With the subnet mask of 255.255.255.0, you'll
have to type in the whole decimal subnet mask.
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Then, so to get, if I want to route
to this network, then I'm going to go
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to 192.168.2.2 which is this one.
213
00:12:56,206 --> 00:12:57,996
This is the actual command.
214
00:12:58,246 --> 00:12:59,556
This is IOS simulator, right?
215
00:12:59,816 --> 00:13:04,316
This is the actual command that I would
type in on router 1 to make it happen.
216
00:13:04,716 --> 00:13:06,696
And I would go on the router
2 and type the same thing,
217
00:13:06,696 --> 00:13:10,636
but instead substitute 1.0 and substitute 2.1.
218
00:13:10,636 --> 00:13:12,476
We're going back to the other direction, right?
219
00:13:12,566 --> 00:13:14,756
So that's what it looks like
to put in a static route.
220
00:13:14,756 --> 00:13:19,126
So when it comes to a default
route, we come to the command.
221
00:13:19,126 --> 00:13:21,186
It would be IP router.
222
00:13:21,556 --> 00:13:27,656
And the command is actually 0.0.0.0 as the IP
address-- let get this little arrow out here.
223
00:13:27,906 --> 00:13:34,216
Then, we would type in 0.0.0.0
as the subnet mask followed
224
00:13:34,216 --> 00:13:38,366
by whatever IP address are ISP gives us, right?
225
00:13:38,366 --> 00:13:39,636
They have a router here.
226
00:13:39,846 --> 00:13:43,266
They're going to give us a public IP
and they'll have an IP that they use.
227
00:13:43,266 --> 00:13:45,556
So it will be on a piece
of paper, they give you.
228
00:13:45,556 --> 00:13:47,226
You'll give them a call, and they'll tell you.
229
00:13:47,226 --> 00:13:56,686
They'll have to give you something that says,
okay, go to 68.110.171.90, let's just say 99,
230
00:13:56,846 --> 00:14:01,366
right, which would be the IP address of our ISP.
231
00:14:01,366 --> 00:14:05,866
So what that tells this router, it says,
if you don't know where to send something,
232
00:14:06,136 --> 00:14:09,686
go and send it to them because
chances are, it's out there somewhere
233
00:14:09,686 --> 00:14:10,946
in the great abyss of the internet.
234
00:14:10,946 --> 00:14:16,586
So millions and millions of routes can dense
into one statement known as a default route.
235
00:14:16,996 --> 00:14:21,586
Let me have one more pointer
to this and plug-in a question.
236
00:14:22,036 --> 00:14:27,026
Let's say, right, let me see
if I can tactfully do this.
237
00:14:27,376 --> 00:14:35,486
Let's say that router 1 had a connection
as well to the internet, right?
238
00:14:35,486 --> 00:14:45,106
And so it has that 68.110.171.90, let's make it
90-- no, let's make it 100, 100 routers, right?
239
00:14:45,226 --> 00:14:47,046
And so it's connected to the ISP.
240
00:14:47,046 --> 00:14:49,896
So we've got, see if you can
follow where I'm going here.
241
00:14:50,036 --> 00:14:52,526
We've got a static route
that says, here's how you get
242
00:14:52,526 --> 00:14:56,686
to the 192.168.3 network or you go that way.
243
00:14:56,896 --> 00:15:00,346
But then, I go on router 1 and I type
in the same default route, right?
244
00:15:00,346 --> 00:15:01,116
That's what I would do.
245
00:15:01,116 --> 00:15:08,266
I would go to router 1 and I would say, but to
get to everything, 0000, 0000, go here, right?
246
00:15:08,516 --> 00:15:19,146
So happy computer on the left comes in and
pings 192.168.3.50 which is this guy over here.
247
00:15:19,986 --> 00:15:23,196
Packy [phonetic] comes to router 1 who
is happy computers default gateway.
248
00:15:23,716 --> 00:15:27,806
Router 1, now looks at its routing table to
figure out where to going, it says, "Okay.
249
00:15:28,016 --> 00:15:34,146
Well, it looks like keeping 192.168.3.50.
250
00:15:34,146 --> 00:15:42,036
It looks like I have a route
that says for 192.168.3.
251
00:15:42,096 --> 00:15:45,666
anything, go ahead and send it over here, right?
252
00:15:45,666 --> 00:15:48,396
But then, I look and I have now a second route.
253
00:15:48,396 --> 00:15:51,606
And it says, send everything
to the internet, okay?
254
00:15:51,606 --> 00:15:53,576
The problem, which does router 1 choose?
255
00:15:53,576 --> 00:15:56,786
Now, you and I looking at the
picture or like, well, duh,
256
00:15:56,786 --> 00:15:57,916
it's over there on the right hand side.
257
00:15:57,916 --> 00:15:59,126
You go that way.
258
00:15:59,126 --> 00:16:01,076
But you got to think like a machine here.
259
00:16:01,326 --> 00:16:02,656
The machine doesn't know that.
260
00:16:02,656 --> 00:16:05,516
The machine is like, I have one route that
says, go this way and I have another route
261
00:16:05,516 --> 00:16:09,426
that looks just this tasty and it's
saying go this way, which one is better?
262
00:16:09,426 --> 00:16:11,826
We come to the rule number
one of routing and this is,
263
00:16:11,826 --> 00:16:15,906
I would say a hugely important
rule that so often gets missed.
264
00:16:15,906 --> 00:16:18,646
It is the rule of-- and I'm going to make it up.
265
00:16:18,646 --> 00:16:20,036
If it's not a word, it needs to be.
266
00:16:20,036 --> 00:16:24,386
It's the rule of specificity.
267
00:16:25,836 --> 00:16:26,856
Specificity.
268
00:16:27,526 --> 00:16:33,536
The more specific a route
is, the better it is, right?
269
00:16:34,726 --> 00:16:36,626
Look at this route over on here.
270
00:16:36,626 --> 00:16:41,126
I say, IP route 192.168.3.0
with this subnet mask.
271
00:16:41,286 --> 00:16:44,366
This is what specifies the specificity.
272
00:16:44,486 --> 00:16:47,026
I'm going to patent that word.
273
00:16:47,206 --> 00:16:47,986
You like it, don't you?
274
00:16:48,236 --> 00:16:50,136
That's what specifies the specificity.
275
00:16:50,136 --> 00:16:51,716
That's how specific the route is.
276
00:16:51,716 --> 00:16:53,246
It says, I'm a class C subnet mask.
277
00:16:53,386 --> 00:16:58,956
This one down here says, I'm a class
nothing, I'm essentially a cache all.
278
00:16:58,956 --> 00:16:59,826
I'm not specific at all.
279
00:17:00,016 --> 00:17:03,806
So I mean, let's make it
a little more pertinent.
280
00:17:04,046 --> 00:17:10,936
Let's say, I put another static route in router
1 and I say, router 1 to reach 192.168.0.0
281
00:17:11,096 --> 00:17:15,866
with the subnet mask of 255.255.0.0, right?
282
00:17:15,866 --> 00:17:21,396
We kind of slap a class C subnet mask on a class
or a class B subnet mask and a class C address.
283
00:17:21,396 --> 00:17:27,446
So essentially this says, to reach anything
starting with 192.168 and then anything
284
00:17:27,446 --> 00:17:30,326
after that, that go ahead
and go this way, right?
285
00:17:30,326 --> 00:17:32,196
And I think it's just strain
a big chicken scratch.
286
00:17:32,426 --> 00:17:39,056
And meanwhile, I still have this route
192.168.3.0 which says, go this way, right?
287
00:17:39,056 --> 00:17:43,616
So if I'm stuck in that world, if I'm stuck in
that decision on router 1, which one is going
288
00:17:43,616 --> 00:17:46,226
to run when, it's the rule of specificity.
289
00:17:46,506 --> 00:17:49,116
Specificity-- I can't even say my own word.
290
00:17:49,116 --> 00:17:52,756
Specificity says, this one is more specific
291
00:17:52,756 --> 00:17:57,706
because it's a more specific subnet mask
thus I'm going to go that direction.
292
00:17:58,076 --> 00:18:01,686
Now if I, again, now you guys
are subnetting masters, right?
293
00:18:01,796 --> 00:18:11,276
But if I created a third route on router
1 and I said, to reach 192.168.0.0, sorry,
294
00:18:11,276 --> 00:18:21,556
let me back that up, to reach 192.168.3.0
with a subnet mask of 255.255.255.128,
295
00:18:22,166 --> 00:18:24,696
think back to your subnetting skills.
296
00:18:24,696 --> 00:18:25,236
What is that do?
297
00:18:25,386 --> 00:18:27,506
That actually cuts this network in half.
298
00:18:27,506 --> 00:18:34,986
You have two networks in 192.168.3.0
through 127 is one that work, network 1.
299
00:18:35,106 --> 00:18:41,576
And 192.168.3.128 through 255 becomes network 2.
300
00:18:41,686 --> 00:18:43,136
That's what that subnet mask does.
301
00:18:43,136 --> 00:18:45,656
So if I created that subnet
mask and I said, okay,
302
00:18:45,906 --> 00:19:00,666
to reach 192.168.3.0 255.255.255.255.128
go that way out to the internet.
303
00:19:00,666 --> 00:19:02,436
Now we have problem, right?
304
00:19:02,436 --> 00:19:08,856
Because when this guy pings
192.168.3.50, it comes in the router 1.
305
00:19:08,856 --> 00:19:18,786
Router 1 says, okay, I have a route
192.168.3.0 with the class C subnet mask saying,
306
00:19:18,786 --> 00:19:23,396
go that way, but now I have a more specific one.
307
00:19:23,526 --> 00:19:33,576
I have a route saying, 192.168.3.0
with a slash 25,
308
00:19:33,576 --> 00:19:36,596
a more specific subnet mask,
it says goes this way.
309
00:19:36,596 --> 00:19:39,786
So now this guy ends up routing
out to the internet.
310
00:19:39,786 --> 00:19:41,676
Well, let's put these concepts
together with a little demonstration.
311
00:19:41,706 --> 00:19:43,206
What I've got here is a small
scenario, we've got three routers.
312
00:19:43,236 --> 00:19:44,886
Router 1, 2, and 3 connected all
around the different networks.
313
00:19:44,916 --> 00:19:46,836
Now all that is been done to this router
is given them a base configuration.
314
00:19:46,866 --> 00:19:49,026
And what I mean by base is given them a
host name, set the console port to logging,
315
00:19:49,056 --> 00:19:49,926
synchronies, and that kind of thing.
316
00:19:49,956 --> 00:19:54,666
Gave them IP addresses, 192.168.3.1
and 192.168.2.1 for router 2.
317
00:19:54,696 --> 00:19:59,976
And then over here on router 1, you can see,
you know, this guy 192.168.2.1 and 192.168.1.2.
318
00:20:00,716 --> 00:20:06,886
Now, sometimes I find early on in the Cisco
occur 'cause I remember it happened to me,
319
00:20:07,196 --> 00:20:09,476
a lot of times I would just
start seeing these diagrams
320
00:20:09,476 --> 00:20:12,456
and I would become numb to the real world.
321
00:20:12,456 --> 00:20:18,686
I'm like they are hockey pucks on a screen with
some squares and clouds, what is this like?
322
00:20:18,686 --> 00:20:23,426
So, this would be an organization maybe it's
a small organization that starting to grow,
323
00:20:23,786 --> 00:20:26,386
maybe they had an office originally.
324
00:20:26,386 --> 00:20:28,786
You know, this would be an office right here.
325
00:20:29,366 --> 00:20:34,156
And that would in California, right?
326
00:20:34,156 --> 00:20:38,226
So, they've got, you know, maybe 50
users sitting here on this network
327
00:20:38,226 --> 00:20:43,456
and they originally had an internet router that
was allowing this site to access the internet
328
00:20:43,866 --> 00:20:46,726
but they eventually start growing and
they're like, "Hey we're going to move
329
00:20:46,726 --> 00:20:49,696
out to Texas 'cause we stole
some customers over there."
330
00:20:49,906 --> 00:20:54,466
So, they brought-- they bought a small little
Texas office, you know, 20 or so users sitting
331
00:20:54,466 --> 00:20:58,336
at that location and they
just brought up a 192.168.3.0.
332
00:20:58,336 --> 00:21:02,586
Again, very usually when you see 192.168
address thing, you're like okay this kind
333
00:21:02,586 --> 00:21:06,806
of like a small office, homegrown
mom and pop shop sort of office,
334
00:21:06,806 --> 00:21:12,576
this just again just the generality of
where you see this 192.168 address is used.
335
00:21:12,576 --> 00:21:18,106
So, they now were like, okay well we want to
connect our office in California to our office
336
00:21:18,106 --> 00:21:21,896
in Texas, you know, Cisco consultant,
Bob can you-- can you make that happen?
337
00:21:22,176 --> 00:21:23,876
So, that's where you come into play.
338
00:21:23,946 --> 00:21:29,676
So, where I would start in I guess
and I stripped all these things down.
339
00:21:29,676 --> 00:21:31,816
So, all these have just based configurations.
340
00:21:31,816 --> 00:21:35,356
I don't even have a default route to
the ISP which would normally be the--
341
00:21:35,356 --> 00:21:40,276
would normally be there would
this have been a real company.
342
00:21:40,596 --> 00:21:42,506
So, we're going to go from scratch, you know,
343
00:21:42,506 --> 00:21:44,686
after we've assigned the IP
address is what do from there.
344
00:21:45,036 --> 00:21:50,566
We're going to start on router 1 for no other
reason than the fact that it says router 1
345
00:21:50,566 --> 00:21:52,036
and that's where you suppose to start.
346
00:21:52,386 --> 00:21:55,106
So, I'm going go on there just
get familiar first of all.
347
00:21:55,616 --> 00:22:01,176
Let's bring router 1 into the picture and
just so I can still see the IP addresses,
348
00:22:01,176 --> 00:22:07,056
I'm going to do a show IP
interface brief and I'm identifying,
349
00:22:07,056 --> 00:22:13,666
okay Serial0/0 which is this
guy right there is 192.168.2.1.
350
00:22:13,666 --> 00:22:17,896
So, that's verified and I've got
FastEthernet0/1 which is connected over here,
351
00:22:17,896 --> 00:22:21,316
that's 192.168.1.2 router 3 is 1.1.
352
00:22:21,316 --> 00:22:23,826
So, I'm just going-- I want
to make sure that I can ping.
353
00:22:23,826 --> 00:22:28,936
I'm going to do some pings 192.168.1.1
that would reach up to router 3.
354
00:22:28,936 --> 00:22:33,176
Sure enough I'm successful, so
this little communication is check,
355
00:22:33,386 --> 00:22:36,006
and I would jump over here to this bridge
356
00:22:36,006 --> 00:22:40,236
and let's just ping 192.168.2.2
which reaches out to router 2.
357
00:22:40,236 --> 00:22:42,126
Okay, so we've got a little check there.
358
00:22:42,126 --> 00:22:44,286
Now, I'm just going to do
something really simple.
359
00:22:44,326 --> 00:22:50,596
I'm going to ping a little
beyond to 192.168.3.1, right?
360
00:22:51,336 --> 00:22:54,676
Which is connected to router 2, should
router 1 know how to reach that?
361
00:22:54,716 --> 00:22:56,546
No, it will not.
362
00:22:57,586 --> 00:22:58,256
But let's prove it.
363
00:22:58,446 --> 00:23:04,846
3.1 and it comes back in its sitting
there with the periods fail, fail.
364
00:23:04,846 --> 00:23:07,006
That the period mean request timed out.
365
00:23:07,006 --> 00:23:07,966
We're not getting there.
366
00:23:07,966 --> 00:23:11,486
I don't know how they get to
that destination and rightly
367
00:23:11,486 --> 00:23:15,606
so because 192.168.3.0 is
not directly connected.
368
00:23:15,956 --> 00:23:16,766
Let's do a new command.
369
00:23:16,766 --> 00:23:19,076
I'm going to do a show IP route.
370
00:23:19,686 --> 00:23:22,396
This command is the life blood of your router.
371
00:23:22,906 --> 00:23:29,086
It shows every single network that the router
knows how to reach and when I look here it says,
372
00:23:29,086 --> 00:23:36,086
"Okay, I only know how to reach
192.16.1.0/24 because I'm plugged into it,
373
00:23:36,086 --> 00:23:37,926
directly connected, right out this port.
374
00:23:37,966 --> 00:23:41,756
You see little C, look up at
the code, C is connected."
375
00:23:41,756 --> 00:23:46,716
So, I'm plugged into it, I also
know how to reach 192.168.2.0.
376
00:23:46,716 --> 00:23:47,946
Its right there Serial0/0, why?
377
00:23:48,206 --> 00:23:49,016
Because I'm plugged into it.
378
00:23:49,016 --> 00:23:50,436
How does it know it's plugged into it?
379
00:23:50,636 --> 00:23:53,566
Because at some point you and I
would have gotten on this router
380
00:23:53,676 --> 00:23:56,346
and we would have assigned an IP
address and as soon as we assign
381
00:23:56,346 --> 00:23:58,926
that IP address the router goes,
"Oh that's what I'm plugged into."
382
00:23:59,656 --> 00:24:00,856
Right? Can you follow that?
383
00:24:01,106 --> 00:24:02,996
So, now I need to educate this router.
384
00:24:02,996 --> 00:24:10,076
I need to say, "Hey router here is, here
is how you get to 192.168.3.0, let's do it.
385
00:24:10,076 --> 00:24:13,126
I'm going to go config T, global config
386
00:24:13,126 --> 00:24:15,766
and then this is the command I just showed
you on the previous slide, IP route.
387
00:24:15,766 --> 00:24:18,346
So, I'm going to say, "I want to route."
388
00:24:18,346 --> 00:24:19,516
Now, where am I going?
389
00:24:19,516 --> 00:24:22,836
And that there's all this other
options that we have here,
390
00:24:22,836 --> 00:24:25,036
but the main one I'm interested
is the destination.
391
00:24:25,166 --> 00:24:30,326
I want to reach 192.168.3.0, the router
says, "Oh, yeah well what it subnet mask?"
392
00:24:30,326 --> 00:24:34,976
255.255.255.0 or prefixed mask, same thing.
393
00:24:34,976 --> 00:24:39,236
So, class C subnet mask and then it
says, "Okay, well how do get there?"
394
00:24:39,356 --> 00:24:41,716
Now, there's a couple ways
I could go about this.
395
00:24:41,716 --> 00:24:44,556
I could say, "Well, go on
and send it out Serial0/0."
396
00:24:44,606 --> 00:24:48,636
And that that would work
okay, but I don't like that.
397
00:24:48,636 --> 00:24:52,496
It's too-- I don't know too vague.
398
00:24:52,496 --> 00:24:56,446
I just-- I deal-- when I deal
with routers, I deal with layer 3.
399
00:24:56,446 --> 00:25:02,556
I don't like just saying, yet go out that that
interface, just go-- like I feel, I feel like,
400
00:25:02,556 --> 00:25:09,666
you know, when we moved into my house we
found these three cats and we kept one of them
401
00:25:09,666 --> 00:25:12,726
but the other two we had to let go and we kind
of to come took them to the door and we're like,
402
00:25:12,726 --> 00:25:15,396
"Okay go Cougar [phonetic],
go Moe [phonetic] go, bye-bye!
403
00:25:15,396 --> 00:25:16,096
Bye-bye, see you.
404
00:25:16,096 --> 00:25:17,466
Bye." You know door slam.
405
00:25:17,766 --> 00:25:22,036
That's why I feel like is-- if
I say to get to this network go
406
00:25:22,036 --> 00:25:25,316
out Serial0/0 well that maybe accurate.
407
00:25:25,316 --> 00:25:28,766
It feels like the router is kind of like,
"Okay open the door, go little pockets go.
408
00:25:28,836 --> 00:25:29,946
Go! Go find your home.
409
00:25:29,946 --> 00:25:34,296
Okay go." Now, it'll work in this case
because it's a point to point link
410
00:25:34,716 --> 00:25:38,696
and it will reach the other side
successfully because that's the only--
411
00:25:38,696 --> 00:25:43,476
it's kind of like it just fell in to a tube
and it happen to go that direction, you know,
412
00:25:43,476 --> 00:25:46,406
that it's kind of like there's no other way
to go so that's where the little cats went.
413
00:25:46,716 --> 00:25:53,866
But, the best way to do it and I'm saying
just to avoid troubles, to avoid weirdness is
414
00:25:53,866 --> 00:25:55,886
to point it to the actual IP address.
415
00:25:56,316 --> 00:25:57,756
Don't say go out this interface.
416
00:25:57,756 --> 00:26:03,846
Tell to reach that, this
network, go to 192.168.2.2.
417
00:26:03,846 --> 00:26:07,296
Again, just from the last time this
is going to something that you know,
418
00:26:07,296 --> 00:26:14,956
192.168.2.2 to reach something that you
didn't previously know, 192.168.3, right?
419
00:26:14,956 --> 00:26:17,076
Good. So, now let's test it.
420
00:26:17,076 --> 00:26:23,296
So, I previously I did the ping to
2.2 successful and then I went to 3.1
421
00:26:23,296 --> 00:26:25,246
and that failed, let's try it now.
422
00:26:26,406 --> 00:26:28,246
Now, we are successful, right?
423
00:26:28,856 --> 00:26:32,946
Because it knows I have to
go through 2.2 to reach 3.1.
424
00:26:33,176 --> 00:26:35,156
We can even do a-- let me do this.
425
00:26:35,156 --> 00:26:38,186
I'm going to do, a no IP
domain look up now just--
426
00:26:38,186 --> 00:26:43,366
that's a command that keeps it from
trying to look up next hop domain names
427
00:26:43,366 --> 00:26:45,216
which just slows this command down to no end.
428
00:26:45,216 --> 00:26:46,996
But I'm going to do a trace route.
429
00:26:46,996 --> 00:26:55,166
Trace route 192.168.3.1 and it just shows
that okay, it's only one hop away and I went
430
00:26:55,166 --> 00:26:58,746
through this IP address to get
there, just again verifies,
431
00:26:58,746 --> 00:27:01,116
verifies that we went there and
it always pings three times.
432
00:27:01,236 --> 00:27:04,136
It always looses the second
ping on the trace route.
433
00:27:04,136 --> 00:27:08,606
The final leg of the thing, there's actually a
whole article, Cisco wrote up a wire that is,
434
00:27:08,606 --> 00:27:10,896
but for now that's the way that we get there.
435
00:27:10,896 --> 00:27:14,666
Now, here's another serial.
436
00:27:14,666 --> 00:27:15,336
Let do this.
437
00:27:15,336 --> 00:27:17,936
I'm going to do-- try IP interface briefing.
438
00:27:18,876 --> 00:27:24,596
Again router 1 and I'm going to do the
same thing ping 192.168.2.2, right?
439
00:27:24,596 --> 00:27:30,396
Feeling good about that, but I'm going to
add to it from the source and I'm going
440
00:27:30,396 --> 00:27:34,536
to say come from the source FastEthernet0/1.
441
00:27:35,396 --> 00:27:36,226
Now, what is that?
442
00:27:36,226 --> 00:27:41,866
192.168.1.2.
443
00:27:42,366 --> 00:27:43,796
Now, why am I doing that?
444
00:27:43,796 --> 00:27:48,646
Because what I'm saying is when this guy
pings this guy, it's of course going to come
445
00:27:48,646 --> 00:27:50,706
from this source because that's-- it's saying,
446
00:27:50,706 --> 00:27:56,076
"Okay my source IP address is 192.168.2.1 that's
the interface that I'm originating this from
447
00:27:56,076 --> 00:27:59,516
and I'm going out-- and I'm going
to the destination of 192.168.2.2
448
00:27:59,516 --> 00:28:01,666
that should work just fine
but I'm changing the game.
449
00:28:01,926 --> 00:28:08,656
I'm saying no, no, no, how about you come from
the source 192.168.1.2 come from this IP address
450
00:28:08,656 --> 00:28:12,306
as your source and try and
ping that same destination.
451
00:28:12,306 --> 00:28:13,836
What do you think will happen?
452
00:28:14,026 --> 00:28:14,996
Success or fail?
453
00:28:15,536 --> 00:28:19,436
It's going to fail, why?
454
00:28:20,136 --> 00:28:25,136
Well, because even though it's coming
in the same link right here to router 2
455
00:28:25,136 --> 00:28:27,776
and you can watch the dots appearing
there, even though it's going
456
00:28:27,776 --> 00:28:35,676
in that same link router 2 now is getting
pockets from the source 192.168.1.2.
457
00:28:36,786 --> 00:28:43,456
It's looking at its routing table and it saying,
"Do I know how to get to 192.168.1.anything?"
458
00:28:43,456 --> 00:28:45,956
No, nobody is told me how to get there.
459
00:28:46,256 --> 00:28:49,946
So, the pockets are getting and they're
being dropped, dropped, dropped, dropped.
460
00:28:49,946 --> 00:28:52,506
Those five drops it does not
know what to do with them.
461
00:28:52,506 --> 00:28:53,356
So, what do we need to do?
462
00:28:53,356 --> 00:28:55,256
We got to go touter 2, right?
463
00:28:56,306 --> 00:28:57,266
Let's do that.
464
00:28:57,526 --> 00:29:01,686
Router 2 is in the game and
we will do show IP route.
465
00:29:03,126 --> 00:29:05,286
I see router 2 is not very smart.
466
00:29:05,286 --> 00:29:07,756
It only knows about its two
connected interfaces,
467
00:29:08,056 --> 00:29:11,816
2.0 and 3.0 which we configured
it from the beginning.
468
00:29:11,816 --> 00:29:16,946
So, I need to go into that router 2 and come
in if you know this pause the nugget now
469
00:29:17,256 --> 00:29:21,126
and write this command-- write down
what I'm going to type in here.
470
00:29:21,266 --> 00:29:22,496
Write down what will fix this.
471
00:29:22,496 --> 00:29:23,636
Okay, unpause.
472
00:29:23,636 --> 00:29:33,046
IP route, 192.168.1.0, even though I
want to specifically reach 1.2 I'm--
473
00:29:33,096 --> 00:29:36,306
routers don't do that, well they
can I don't want to do that.
474
00:29:36,306 --> 00:29:41,786
I want to say to reach that whole network, to
reach everything on that network with a 255.
475
00:29:41,856 --> 00:29:44,486
255.255.0.
476
00:29:44,486 --> 00:29:49,826
Router 2 you need to go to 192.168.2.1.
477
00:29:50,326 --> 00:29:54,136
Again, router 2 knows how to get here, right?
478
00:29:54,136 --> 00:29:59,966
To the 1, so, we're saying use that guy
because he knows how to reach 192.168.1.0.
479
00:30:01,356 --> 00:30:06,826
It's like a big train that we're building, you
know, one by one by one we bring these links up.
480
00:30:06,986 --> 00:30:13,826
So now, I can come back to router 1
and do the same command, you know,
481
00:30:13,826 --> 00:30:19,986
ping him again from a source of
192.168.1.2 and now we have success, why?
482
00:30:19,986 --> 00:30:21,516
Because router 2 knows how to get back.
483
00:30:21,516 --> 00:30:22,176
He is saying, "Okay.
484
00:30:22,516 --> 00:30:26,046
Now it's coming from the source
and somebody just educated me how
485
00:30:26,046 --> 00:30:27,666
to reach this entire network."
486
00:30:28,706 --> 00:30:30,136
Now what about router 3?
487
00:30:30,586 --> 00:30:34,946
Router 3 up here has been out in the
cold, he doesn't really know anything.
488
00:30:34,946 --> 00:30:41,606
I mean-- well he knows how to get his
connected network, 192.168.1.0, right?
489
00:30:41,606 --> 00:30:45,926
And he knows how to get to ISP, not the
internet, he just knows how to get this network
490
00:30:45,926 --> 00:30:50,646
between him and the ISP, so he's got a lot
of work that we need to do for him, right?
491
00:30:50,976 --> 00:30:53,896
So it should be pretty fast now
that we know what we're doing.
492
00:30:53,896 --> 00:30:58,196
So let me just clear off all this
gibberish and let's go to router 3.
493
00:30:58,596 --> 00:31:01,916
Here we are in this blank little config screen.
494
00:31:02,236 --> 00:31:11,006
Let's do a show IP interface brief on him and
we see, yup, he knows how to get to his ISP.
495
00:31:11,006 --> 00:31:16,916
He's on that network and he knows
how to reach to 192.168.1 network,
496
00:31:16,916 --> 00:31:18,886
but if I do show IP route, he
doesn't know anything else.
497
00:31:19,096 --> 00:31:24,106
So he can't get to-- he doesn't know
how to reach this WAN link, 192.168.
498
00:31:24,106 --> 00:31:27,856
2 or this network over here and
I just prove it to you quickly.
499
00:31:28,216 --> 00:31:31,936
192.168.2.1, we're not getting anywhere.
500
00:31:32,116 --> 00:31:32,996
He doesn't know how.
501
00:31:33,226 --> 00:31:37,006
Control-Shift-6 by the way will
break you out of a ping that's stuck
502
00:31:37,006 --> 00:31:38,846
if you don't want to wait for all of it to fail.
503
00:31:39,286 --> 00:31:42,276
Control-Shift-6, you have to
hold it all down and, you know,
504
00:31:42,276 --> 00:31:45,296
kind of hit them all at the same time.
505
00:31:45,296 --> 00:31:47,626
All right, so I can add some route.
506
00:31:47,626 --> 00:31:48,576
So I'm going to do IP route.
507
00:31:48,576 --> 00:31:49,816
Again pause the negative.
508
00:31:49,816 --> 00:31:51,376
You know where I'm going and think through it.
509
00:31:51,816 --> 00:32:00,846
192.168.2.0, so to reach the two network,
255.255.255.0 go to, who's it going to?
510
00:32:01,076 --> 00:32:10,656
192.168.1.2, I'm saying go here
in order to reach here, right?
511
00:32:10,656 --> 00:32:12,206
Now some of you might be looking at this switch.
512
00:32:12,206 --> 00:32:14,416
I mean like what, what role does he play?
513
00:32:15,166 --> 00:32:15,996
Cable connector?
514
00:32:16,366 --> 00:32:17,226
That's about it.
515
00:32:17,366 --> 00:32:19,756
I mean normally you won't even see this run.
516
00:32:19,756 --> 00:32:21,416
By the way, these guys are all peripheral.
517
00:32:21,636 --> 00:32:26,366
If you download the GNS3 typology that
I'm using to create the scenario, this--
518
00:32:26,366 --> 00:32:28,896
I don't even know if I put a
configuration on these guys.
519
00:32:28,896 --> 00:32:33,196
They're just there for the
picture, but photo app, right?
520
00:32:33,196 --> 00:32:36,686
But this guy is normally drawn,
the people don't even draw him.
521
00:32:36,686 --> 00:32:41,306
You see diagrams like this to where
you see, you know, these guys.
522
00:32:41,506 --> 00:32:45,526
So the switch just becomes the
line because all that guy is kind
523
00:32:45,526 --> 00:32:46,976
of connecting everything together.
524
00:32:46,976 --> 00:32:48,546
He doesn't really participate.
525
00:32:48,546 --> 00:32:49,576
We're going through him.
526
00:32:49,576 --> 00:32:52,266
He learns the Mac addresses
but we're talking layer three.
527
00:32:52,266 --> 00:32:53,816
We don't deal with IP addresses.
528
00:32:53,816 --> 00:32:57,566
All that stuff is now assumed
that was earlier in the series.
529
00:32:57,826 --> 00:32:59,676
So we can come back here hit the up arrow.
530
00:32:59,676 --> 00:33:01,106
Well let's just prove it now.
531
00:33:01,546 --> 00:33:07,076
I'm going to do a ping 192.168.2.1 groovy.
532
00:33:07,236 --> 00:33:07,956
We're getting there.
533
00:33:07,956 --> 00:33:11,196
Let's go 2.2, groovy, so
we're able to reach everything
534
00:33:11,196 --> 00:33:14,376
on that two network, but what about 3.1 now?
535
00:33:14,996 --> 00:33:16,586
Fail. Nothing.
536
00:33:16,586 --> 00:33:17,276
Not getting there.
537
00:33:17,576 --> 00:33:19,516
So Control-Shift-6 break that.
538
00:33:19,516 --> 00:33:20,846
Hit the up arrow a couple of times.
539
00:33:21,706 --> 00:33:27,416
There's my static route and
I'm going to 3.0 that network
540
00:33:27,416 --> 00:33:30,686
over there on the right, go to 192.168.1.
541
00:33:30,686 --> 00:33:34,006
same place because router 1 has a
static route that gets in there too.
542
00:33:34,506 --> 00:33:35,406
Putting in place.
543
00:33:36,056 --> 00:33:37,026
Bam. Look at that.
544
00:33:37,026 --> 00:33:39,076
Isn't it-- it's kind of cool to do static route?
545
00:33:39,076 --> 00:33:40,406
It's definitely one of those
546
00:33:40,406 --> 00:33:44,586
like I've accomplished something today feelings
'cause you really are bringing up networks.
547
00:33:44,586 --> 00:33:49,336
Now, this works great for networks the size
of what we're looking at on the screen.
548
00:33:49,856 --> 00:33:53,416
But the more and more this grows
you add four, five, six routers.
549
00:33:53,416 --> 00:33:57,726
I mean the amount of work you have to
do begins to increase exponentially,
550
00:33:57,726 --> 00:34:01,416
every new sites that's added you have to
go to every location every router and say,
551
00:34:01,696 --> 00:34:03,596
okay, to get here do this, do this.
552
00:34:03,596 --> 00:34:06,286
Now, the key about static routing is it's good.
553
00:34:06,286 --> 00:34:07,346
It works well.
554
00:34:07,796 --> 00:34:10,736
You just need to know when to convert from it.
555
00:34:10,736 --> 00:34:15,466
You got to say, okay it's time to make a
leap from static routing to something else
556
00:34:15,466 --> 00:34:20,436
and that's going to be what we talk about in
the next nugget as we get into dynamic routing.
557
00:34:20,436 --> 00:34:27,906
One more piece that's missing though, router
3, yeah he's got an internet connection,
558
00:34:28,136 --> 00:34:31,246
meaning the ISP is coming
in right here on this cable
559
00:34:31,556 --> 00:34:34,296
but we don't have a route to reach the internet.
560
00:34:34,766 --> 00:34:39,726
So what I need to do is go in here and do IP
route, remember I was saying a default route.
561
00:34:40,496 --> 00:34:49,446
Everything zeroes, everything
zeroes, 68.110.171.99, Enter.
562
00:34:49,446 --> 00:34:54,186
Now I'm assuming, just made a big
assumption that the ISP is actually 99.
563
00:34:54,186 --> 00:34:59,056
Now let me just say, in this scenario
there is no ISP and when I went into GNS3
564
00:34:59,056 --> 00:35:02,966
and created this, I actually converted
one of my computers and just said, no,
565
00:35:02,966 --> 00:35:06,096
you're a cloud [laughs] and it's not
really a cloud, it's just a computer.
566
00:35:06,096 --> 00:35:08,956
I just said, "Look like a
cloud," but it's not real.
567
00:35:08,956 --> 00:35:12,756
But that's what-- that's the only
thing that I would have to do to bring
568
00:35:12,756 --> 00:35:13,826
that up that internet connection.
569
00:35:13,826 --> 00:35:14,996
Now I'm not going any further.
570
00:35:14,996 --> 00:35:18,766
I'm not making this internet connectivity
real and I will later in the series
571
00:35:19,016 --> 00:35:22,726
because there's other things
that have to be in place
572
00:35:22,726 --> 00:35:27,556
to make this whole thing work primarily the one
being in that net-- network address translation.
573
00:35:27,556 --> 00:35:29,016
We haven't gone there yet.
574
00:35:29,016 --> 00:35:34,736
Now all of these other routers because I'm using
static routing need a default route too, right?
575
00:35:34,856 --> 00:35:39,456
So I'd have to go-- this is the beauty of static
if you're paid by the hour, you go in there now
576
00:35:39,566 --> 00:35:43,716
to router 1 and I say, okay IP
route to get to the internet for you
577
00:35:43,716 --> 00:35:49,406
from your perspective go to 192.168.1.1, right?
578
00:35:49,406 --> 00:35:52,426
So 'cause from router 1's
perspective, he's going to router 3
579
00:35:52,796 --> 00:36:01,966
and from router 2's perspective right
here, do a show IP route on him.
580
00:36:02,166 --> 00:36:08,086
He only knows how to reach, he's got
static, you see that 192.168.1.0.
581
00:36:08,086 --> 00:36:10,106
By the way, we haven't talked
much about this yet.
582
00:36:10,106 --> 00:36:15,326
We will. This actually represents the
administrative distance and the metric.
583
00:36:16,116 --> 00:36:20,576
When we get to the next nugget, we'll
start looking at-- actually did I put that?
584
00:36:20,576 --> 00:36:21,146
I think I did.
585
00:36:21,346 --> 00:36:26,256
What administrative distances
how believable is this route?
586
00:36:26,556 --> 00:36:28,946
One is actually a really, really, really,
587
00:36:29,076 --> 00:36:34,596
really good administrative distance that's why
almost the best that you can get because you
588
00:36:34,596 --> 00:36:38,236
as an administrator told this
router this is what you do, router,
589
00:36:38,236 --> 00:36:42,886
and the router sometimes do its
detriment believes you and me.
590
00:36:43,136 --> 00:36:47,556
The second one is the metric
as in how costly is this route?
591
00:36:47,846 --> 00:36:52,366
That's when we start talking about, how, you
know, how does the router find the best route?
592
00:36:52,366 --> 00:36:53,786
It's going to be the one with the lowest cost.
593
00:36:53,786 --> 00:36:55,236
Now this looks like a really, really,
594
00:36:55,236 --> 00:36:59,266
really good route because it has a
cost of zero but more on that later.
595
00:36:59,266 --> 00:37:02,866
So it's saying, to reach this guy with
really good administrative distance
596
00:37:02,866 --> 00:37:05,986
and really good costs, go
to here in the [inaudible].
597
00:37:06,766 --> 00:37:08,276
So we now have to add in.
598
00:37:09,556 --> 00:37:15,796
But to get to everything
else, go to 192.168.2.1.
599
00:37:16,356 --> 00:37:20,266
Again router 2 from its perspective, he
says, "I'm going to send everything to here";
600
00:37:20,586 --> 00:37:23,166
and router 1 says, "well I've been
configured to send to everything to here";
601
00:37:23,356 --> 00:37:26,246
and router 3 it says, "well I've been
configured to send everything to here."
602
00:37:26,246 --> 00:37:31,336
So you kind of create this chain of send to
everything and now when I do a show IP route
603
00:37:31,576 --> 00:37:33,876
on any of these routers, this
is the first one I'll show you.
604
00:37:34,166 --> 00:37:36,336
You can see that I have this
side note this little star.
605
00:37:37,126 --> 00:37:40,936
The star if we look at the
keys says, "candidate default"
606
00:37:41,336 --> 00:37:46,596
and you also notice previously it
was saying, I don't where I'm going.
607
00:37:46,596 --> 00:37:50,326
I don't have a gateway of last
resort, like I don't how to get there.
608
00:37:50,326 --> 00:37:50,826
I'm standing here.
609
00:37:51,016 --> 00:37:54,376
But notice after we put in the static
route, its saying, okay now I do.
610
00:37:54,946 --> 00:37:58,146
Now I know if everything else, last resort.
611
00:37:58,146 --> 00:38:05,096
It's kind of like, if all else fails, I'm
going to send the pocket to 192.168.2.1
612
00:38:05,296 --> 00:38:08,216
because that's what I was just
configured with, with that default route.
613
00:38:08,216 --> 00:38:10,846
So you can think of static
routing like a big scavenger hunt.
614
00:38:10,846 --> 00:38:15,046
Ever done a scavenger hunt where, you know, you
either have probably a team of people that's
615
00:38:15,046 --> 00:38:19,026
with you and you get envelope number one
and then in the envelope it says, you know,
616
00:38:19,026 --> 00:38:24,766
go to a store in the mall that
starts with the letter sport.
617
00:38:25,266 --> 00:38:28,576
I guess that's-- obviously I didn't
do that with this scavenger hunt.
618
00:38:28,706 --> 00:38:30,476
Starts with the word sport, right?
619
00:38:30,476 --> 00:38:33,446
And do you get-- you go to the
store in the mall and the store
620
00:38:33,446 --> 00:38:36,286
in the mall you find another
envelope there and it's like, okay,
621
00:38:36,456 --> 00:38:38,916
now got to the, you know, what I mean.
622
00:38:39,046 --> 00:38:42,826
So you kind of keep going with all of
this envelopes until you are the first
623
00:38:42,826 --> 00:38:47,156
and you win a price and that's really what
static routing is, is we're kind of creating all
624
00:38:47,156 --> 00:38:51,176
of these little links that's the feel that you
get as you configure these devices, it's like,
625
00:38:51,176 --> 00:38:57,586
okay to get to the 192.168 go here
and when he get there they're like,
626
00:38:57,586 --> 00:38:58,456
no, no, no, actually go here.
627
00:38:58,456 --> 00:39:01,626
But you as the router-- you as the
administrator have to go in there
628
00:39:01,626 --> 00:39:04,996
and statically place each
one of those envelopes.
629
00:39:05,476 --> 00:39:10,096
In one sense, it's good because you
have complete control over everything
630
00:39:10,096 --> 00:39:12,696
and if something fails it's your fault.
631
00:39:12,696 --> 00:39:13,866
You know that you did something wrong.
632
00:39:13,866 --> 00:39:19,846
It's very simple when you look at static
routing but also from a overhead perspective,
633
00:39:19,846 --> 00:39:23,896
you can see that can really start
being a lot of work especially
634
00:39:23,896 --> 00:39:28,336
when you start having many
different past in your organization
635
00:39:28,336 --> 00:39:30,956
and many different sites it
just becomes plain overwhelming.
636
00:39:30,956 --> 00:39:36,116
So static routing, works well for small
organizations not so well for large.
637
00:39:36,686 --> 00:39:42,306
That being said you almost always
find it in every company in some form.
638
00:39:42,306 --> 00:39:45,226
You'll find some device with the
static route and put in there.
639
00:39:45,226 --> 00:39:48,476
So we have seen in this nugget
the purpose of routing kind
640
00:39:48,476 --> 00:39:50,886
of taking us back, big picture, what is routing.
641
00:39:51,336 --> 00:39:54,366
We looked to how static routing
can help us accomplish our goal
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of educting the routers manually.
643
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And then we looked at some configuration
and design scenarios for static routing.
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I hope this has been informative for you
and I would like to thank you for viewing.
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