All right, it's time for our configuration
and troubleshooting lab number 1 regarding virtual links.
[MUSIC PLAYING]
And here, my friend, is the task for this virtual app.
I would like you to take this network, which is 10.78.0.
And it's connected directly on R7 on serial 3/1 and R8 3/2.
And I'd like you to add that as part of area 78.
Now, area 78 currently doesn't exist.
But I'd like you to add that. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
But I'd like you to add that.
And then what I'd like to do is make sure
that network, 10.78, shows up in the entire OSPF domain,
and as a test, from a PC up here on 10.0.1 network.
And there's a couple options.
There's a virtual machine, a little VM on a tab,
and there's also a Windows 10 virtual machine
up on that network.
The goal would be able to ping or have reachability
to this interface IP address of 10.78.0.8.
And that's the goal. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And that's the goal.
Now, as part of this, the only requirement I have
is that we leave this network, 10.78, in area 78.
And beyond that, there are several possible solutions
to making this work involving virtual links.
And so anyway you choose to solve it is fine.
So go ahead and pause me now.
Work on this lab.
And then when you're ready, click on resume,
and we'll do the walkthrough together.
All right, welcome back.
Now, regarding the solution to this, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Now, regarding the solution to this,
we could do several things.
We have this area right here, which is area 78.
We could go ahead and do a virtual link between R7
and the area border router in area 1, making that
a transit area.
That would work.
Unless there's something preventing us in this area
from doing that.
And, in fact, in this lab, this area is a stub area.
So you can't create a virtual link in a stub area.
So an option of that would be to remove the stub area,
make it a normal area. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
make it a normal area.
And then we could use the virtual link
or we could go up this side.
We could have R8 do a virtual link between it and R4.
And that would work.
So that's an option as well.
And actually, one other option is
we could include this network here, which
I believe is the 10.38 network.
And we could include that in area 78.
And that would mean R3 would be an area border
router for area 78, which would include these two networks.
And that would be OK, because area 78 would then WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And that would be OK, because area 78 would then
have an area border router.
So any way we want to choose to slice this,
the exercise I wanted you to do is to see that if you try to do
it up this way, between R3 and R7, we can't.
So I'm going to avoid trying to do it through a stub area
because it complains.
It doesn't work unless you take off this stub area
and make it a normal area.
So what I propose we do is let's--
let me back this off a little bit.
Let's-- for the solution, let's go ahead and configure--
you know, we have this serial link here, which is not great.
We have a serial link here, which is not great. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
We have a serial link here, which is not great.
But I already have this area, area 2.
So I'm going to go ahead-- for my solution here,
I'm going to go ahead and build a virtual link between R8
and R4.
The router IDs are 4444 and 8888.
So let's build a virtual link between those.
And then we'll verify that that network in the 78 area
is then visible to the rest of the network.
So that's our plan.
Let's go ahead and go directly down to R8
and start the tunnel.
And here on R8, we'll just do a show IP ospf interface brief. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And here on R8, we'll just do a show IP ospf interface brief.
Oh, yeah.
Part of our requirement was to put that interface into OSPF
area 78 as well.
So let's do that first.
Config t.
OK, serial 3/2.
IP-- I said 3/2.
But my fingers didn't.
OK, IP ospf area--
ospf process 1 area.
And it's going to be in area 78.
OK.
And we want to do the same thing over on serial 3/1 over on R7. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And we want to do the same thing over on serial 3/1 over on R7.
It's going to copy that.
Go to R7, do a quick show IP interface brief.
Config t, interface serial 3/1.
Paste that in.
And there's our neighborship.
Sounds great.
So now we have that network in area 78.
Unfortunately, no one else can see it.
So let's build our virtual link on R8,
going up to R4 on the right hand side of our topology.
So we'll go OSPF configuration mode, router ospf 1. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So we'll go OSPF configuration mode, router ospf 1.
And area.
This is area 2 on the right hand side.
Area 2, virtual link.
And we're going to go to the area border router
R4, which is 4444.
Great.
And then we're going to do the same thing on R4.
We'll go to R4.
Config t.
Router ospf 1.
And area 2 virtual link and point down to 8.8.8.8.
And so we should have a full adjacency
here in just a moment. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
here in just a moment.
Show IP ospf-- it usually happens very quickly.
But I don't see it.
Let's do a show IPv6--
Let's do a show IP ospf interface brief.
So there's our virtual link interface.
It says down.
No neighbors.
All right.
Well, let's-- let me just verify our neighborships are OK
in our routes.
So in our topology, R4 should be adjacent with R6.
R6 should be adjacent with R8. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
R6 should be adjacent with R8.
And if any of those are broken for any reason,
we're not going to get--
we don't have reachability across that area.
So let's check our neighborships here on R4.
Also, just like before, I'm injecting not only virtual link
issues, but also at least one or two other problems
to help keep us on our toes.
And that's what I think we're experiencing here.
Show IP ospf neighbors.
OK.
So we've got R3, R2.
But no R6.
Let's do a show IP ospf interface brief.
WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So it shows that--
let me just verify our interface here.
So from R4's perspective, it should be serial 3/1,
which is right here.
And no neighbors and no adjacencies.
Huh.
This is area 2, which is correct.
OK.
Let's do a debug.
IP ospf adjacencies.
And debug IP ospf hello. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And debug IP ospf hello.
All right.
OK, well, I'm going to turn off debugging
because that's enough.
Undebug all.
So I love a good debug now and again.
So this says received hello from 6666 area 2.
That's this IP address.
Great.
Mismatched hello parameters.
So here, it's showing us the problem. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So here, it's showing us the problem.
It's saying that it received 120, and my current was 40.
The hellos received was 30.
My current is 10.
And as a result, they're not going to play.
So the timers on the other side--
the default for P2P is 10.
So if we look at the other side real quick-- let's
just do a show IP ospf interface for serial 3/1.
So there's our timers right there.
And if we go over to R6 and do a show-- WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And if we go over to R6 and do a show--
do a show IP ospf interface for serial 3/2,
it's just going to confirm that interface before I do a show.
Yeah, 3/2.
And its timers are definitely different.
And that's also because somebody set the network type to point
to multipoint, which uses those timers
that we see in front of us.
So let's change that interface serial 3/2 no IP ospf network
type.
That'll allow the default to take place. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
That'll allow the default to take place.
Then we have our full adjacency.
Fantastic.
And if we go back to R8, let's do a show IP ospf neighbor.
Wow.
I don't have my virtual--
did we not configure the virtual link on R8?
Oh, there it is.
OK, great.
So it just came up.
There's the virtual neighbor, 4444.
Now we'll do a show IP ospf neighbor. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Now we'll do a show IP ospf neighbor.
Ah, much better.
So we have full adjacency via our virtual link.
And now that network of 10.78, if we go up
to R1 in the backbone, show IP route.
There's the 10.78 network.
And if we go to a client, so here's PC1.
Here's its IP address.
Oh, no IP address.
It's not going to have a very easy time.
Let's do a-- mm-hmm. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Let's do a-- mm-hmm.
OK, well, I'm going to show you how to configure an IP address
on this device if you want to.
IP-- OK.
IP address 10 dot--
this is area 0.
So 0.1.-- and let's use 123.
I don't think that's being used-- slash 24,
with a default gateway of 10.0.1.1, which is R1.
10.0-- why is it invalid IP address. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
10.0-- why is it invalid IP address.
Oh, maybe it doesn't like the--
oh, I see.
It didn't like the keyword "add."
Nobody likes "add."
All right.
So IP-- the IP address, the mask.
And let's do a ping to 10.0.1.1.
That should be R1.
Oh, there we go.
Great.
So in our topology, that's a PC up here on the 10.0.1 network.
And it has a correct default gateway.
We just pinged it.
Let's verify that we can ping down to 10.78.0.8, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Let's verify that we can ping down to 10.78.0.8,
which is our goal.
So let's just do a trace to-- on this little VM,
let's do a trace.
10.78.0.8.
All right.
From 1 to 2 to 4 to 6 to 8.
Fantastic.
There's also-- in the lab, there's
little client PC over in the lab environment,
so you can click on that and bring it up.
And the password to log into the client
is over on the right hand side in the controls.
And let's just verify we can get there as well from here. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And let's just verify we can get there as well from here.
So we'll go to a command prompt.
I'm going to right click on the Windows icon.
And there's an option on this version of Windows 10
for a command prompt right here.
And we'll just do an IP config.
And our IP address on this PC is 10.0.1.10.
Our default gateway 10.0.1.1.
And if we do a trace--
that's how you spell trace in a Windows computer--
T-R-A-C-E-R-T space.
I do a dash d for don't bother doing name resolution.
And let's go to 10.78.0.8. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And let's go to 10.78.0.8.
So our first stop is R1, then R2, then R4, then R6, then R8.
Fantastic.
So in this video and hands-on lab,
we injected a virtual link in area 2
because area 1 was a stub.
We also had some troubleshooting with the neighborships
in R4 and R6.
All part of the game called getting better and better
at troubleshooting OSPF networks.
So I've got one more lab for you regarding virtual links
with IPv4.
And that's coming up in just a moment. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And that's coming up in just a moment.
Meanwhile, I hope this has been informative for you,
and I'd like to thank you for viewing.