All right, my friend.
It is time for troubleshooting ticket number two.
[MUSIC PLAYING]
So here's the scenario for this troubleshooting lab--
we have asked somebody in our company, our environment,
to go ahead and implement a bypass so we
wouldn't need virtual links.
So what they did was they implemented GRE tunnels.
And so this network here--
this is between R7 and R8--
this is in Area 78, or it should be,
and to make it work because this is an NSSA area, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
and to make it work because this is an NSSA area,
they implemented tunnels.
So the syntax for the tunnels--
we provided it to them, it's right here.
So on R3, the tunnel says interface Tunnel0
and for IPv6, its address on that tunnel
is going to be this, so this address should
be on the same network as this address.
So they're both on the same 37 network, which is good.
And then on R3, it says that we have the source
address for the tunnel.
It's going to be this.
And the destination is this and vice-versa. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And the destination is this and vice-versa.
R7 says the tunnel source is its own IP address,
and the destination end of the tunnel
is the IPv6 address for R3.
That looks good.
It also specifies the tunnel mode IPv6.
And they've also added this interface,
this logical interface, to Area 0,
which means R7 is now connected to Area 0.
It can be an area border router for 78.
The objective in this lab is to find out what's not working.
Why is this configuration not working? WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Why is this configuration not working?
Our goal is to be able to ping the 2001:DB8:6783:78::8,
which is the interface here on R8 from anywhere in the OSPF
network.
And something about the configuration
has gone awry, so here's what I'd love you to do--
I'd love you to look at what should
be here in the configuration, what should be reachable,
and then using the hands-on lab, go ahead and troubleshoot WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
and then using the hands-on lab, go ahead and troubleshoot
and resolve the problems to get full connectivity once again.
So if you are logged on to the CBT Nuggets website, awesome.
Good start.
Click on the link for the virtual lab,
hit Pause on this recording here so
that you can actually work on it on your own,
and when you're ready, click on Resume.
And in just a few moments, we'll do the walkthrough together.
All right, and here we go.
Let's start off on-- WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Let's start off on--
so here's the topology with the information on the tunnels.
And let's just verify the tunnels are up.
And so a couple easy ways of doing that-- you know,
in the lab, we can't look at the running config,
but what we can do is go to R3 and do a show ip interface
brief--
[LAUGHING]---- ipv6 interface brief.
OK, So if we look down to Tunnel0,
here we can verify our IP addresses is WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
here we can verify our IP addresses is
2001:DB8:6783:37:3, so 37 represents the logical tunnel
network between R3 and R7.
That looks good.
And let's just go to R7 and check those as well.
Show ipv6 interface brief, and it's got 2001:DB8:6783:37:7.
OK, so the IPv6 addresses are correct on the logical tunnel
interface.
Let's take a look-- WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Let's take a look--
let's do a show ipv6 ospf neighbors.
Let's see if we have a neighborship.
OK, so based on this tunnel going between R3 and R7,
and both of them being enabled for IPv6's OSPF Area 0,
there should be a neighborship, so let's take a closer look.
Let's go back and let's go to R3.
Hm.
Oh, up-- there we go.
Up/down, right there. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Up/down, right there.
That's our big indicator that something
is fishy or not going right.
Let's do a-- since we're here, let's see if R7 says that too.
Oh look, it says the tunnel is up/up.
Hm.
So R7 says up/up, R3 says up/down.
Let's go take a look at R3 then.
All right, let's do a show ipv6 interface tunnel0. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
All right, let's do a show ipv6 interface tunnel0.
OK, so that just shows the address.
Let's see what else we do here.
Let's do a show interface-- let's just
take a look at the details for the tunnel itself--
show interface tunnel0.
And let me clear off the screen and do that again.
All right.
So this is saying that the Tunnel0 is up, line protocol is
down and encapsulation is TUNNEL, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
down and encapsulation is TUNNEL,
right, and tunnel source is this.
Now, is that the IPv6 address of R3--
2001:DB8:6783:35::3.
Taking a look at our topology, that's between R3 and R5--
that should be the 35 network.
OK, that part looks OK.
And the destination is 2001:DB8: 6783:75::7, and that is--
oh, R7 should be 57::7, not 75::7, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
oh, R7 should be 57::7, not 75::7,
so it's got the wrong destination address
on the tunnel to start with.
So let's solve that.
Let's take it to that part and do a Q there,
config t, interface tunnel 0, and tunnel destination--
let's take a look at our syntax here.
So our syntax is tunnel, destination should be 57::7.
All right. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
All right.
So tunnel destination, right-click, 57::7.
All right, so check that out.
Not only did our-- looks like our tunnel come up,
but we also have the full adjacency based on the message.
Let's do a show ipv6 ospf neighbors.
Well, this might be easier than we thought.
So we have a full adjacency.
And now, let's verify whether or not WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And now, let's verify whether or not
we can see this network right here.
Let me go ahead and add it.
This is the 2001:DB8:6783:--
and it's between R7 and R8--
78:: network.
And let's see if we can see that network because our goal is
to make sure we can see that network everywhere-- or reach
it everywhere in the OSPF domain.
So let's go back to R1 and see if he can see it.
So on R1, we'll do a show ipv6 route for ospf learned routes, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So on R1, we'll do a show ipv6 route for ospf learned routes,
and we're looking for 78.
There's 68-- I don't see it.
All right, well let's go make sure
that R7 is including that--
show ipv6 ospf interface brief.
Oh, OK-- the serial interface, this guy right here,
serial 3/1 is not enabled for OSPF
for area 78, which it should be as part of what we asked
the junior technician to do. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
the junior technician to do.
So let's enable that interface, serial 3/1 for OSPF version 3.
We'll put it into area 78 and that certainly
would cause the networks in that area not to show up.
So let's fix that.
So here on R7, config t, show ipv6 interface brief just
to make sure I get the right interface-- very important.
So that is interface serial 3/1, it has that network.
So config t-- we're already there-- WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So config t-- we're already there--
interface serial 3/1 ipv6 ospf 1 area 78.
OK, and we got a neighborship with R8,
across that serial link.
So now with that adjacency, let's see whether or not
that network shows up on R1.
So on R1 a moment ago, we didn't have the 78 network.
Let's do the show ipv6 route ospf--
looking for 78.
There it is.
And let's also do a trace to 2001:DB8:6783 and we'll go WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
And let's also do a trace to 2001:DB8:6783 and we'll go
to 78::8.
R1's doing the trace.
It goes to R3, and R3 has an adjacency with R7,
so that's the next hop.
And then the final hop is R8 over here at this interface,
with :8 as its IP address.
So from R1 to R3 to R7 and R8.
Let's verify that happened.
And sure enough, starting from R1 next hopping
R3 then R7 and R8.
In this video, we've had the opportunity WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
In this video, we've had the opportunity
to do some hands-on troubleshooting
with OSPF version 3 once again.
And this time, we had some misconfigured GRE tunnels
that worked, hoping to alleviate the need for virtual links,
but the GRE tunnels were not configured correctly.
And also, we had OSPF that wasn't even enabled
on one of the links, which was an additional problem.
So thanks for joining me in this set of troubleshooting labs,
and I'll see you in the next set of videos.
Meanwhile, I hope this has been informative for you,
and I'd like to thank you for viewing.