[AUDIO LOGO]
Now that we've looked at some of the details of OSPF version
three, it's time to jump in to the command line and get it up
and running.
So let's begin by looking at our topology again.
So we have an idea where we need to configure it,
on which routers and which interfaces.
And then we'll jump into the command line
and get OSPF version configured on the routers that
still need it.
So once again, we'll be using OSPF version
three topology one.
So have this handy as we go through.
And what we need to configure here
is routers six, one and two.
The other routers here should already
be configured with basic OSPF routing.
In other words, they're not doing authentication
or anything like that.
Just the basic OSPF implementation.
Also keep in mind as we go through here,
IPv6 addresses are already configured
on all of the interfaces including on routers one, two
and six.
And also on iOS XE such as router six
here, IPv6 unicast routing has also already been enabled.
So we will literally just be configuring OSPF version three.
So let's go ahead and get started.
We'll jump into the command line on router one.
So as we'll see as we go through this configuration,
this is actually very similar to configuring OSPF version two.
So of course, we go into configuration mode.
Now here's of course, the big difference.
We're going to say OSPF version and then give it
a process number.
We're going to go ahead and configure our router ID.
We go into our area.
So we'll configure area zero first here on router one.
We'll put our loopback interface in area zero.
And let's go ahead and do passive enable on that.
No need to send hellos and search out that interface.
Then we'll go into interface gig 0/0/0/1.
This is also an area zero.
This one, however, is going to be a point to point interface.
So we simply configure point to point.
And then interface gig 0/0/0/3 goes in area zero.
But this is a multi access network,
so it does not get point to point.
That you take care of area zero.
So let's configure area 100.
This gets interface gig 0/0/0/0.
This is also point to point.
That should take care of this configuration.
Let's go ahead and commit our changes.
We see some neighborships already coming up.
So our neighborship with router seven and router three
have both come up.
We wouldn't expect our neighborships with router two
and router six yet because of course, we
haven't configured those.
So let's exit out of configuration mode
and let's just do some verification.
So let's start with just to show OSPF version three interface
brief.
We see that we have R1 interface,
gig 0/0/0/0 in area 100.
And we see that our other interfaces, gig 0/0/0/1,
0/0/0/3, and loopback 0 are all in area 0.
We also see that they're configured as either point
to point.
Or we see in the case of gig 0/0/0/3,
that it has been elected as the BDR on that particular segment.
So that looks good.
Let's go ahead and verify our neighbors.
We can see, of course, that we have neighborships with router
seven and router three.
Now, we saw those come up, of course.
So this would have been expected but we just want to verify.
So these are both up.
We can also see here where router seven has
been elected as the DR. Which makes a lot of sense
because we're the BDR.
And at the moment there's only those two routers
active on that multi access segment.
Let's also do a show OSPF three route.
This is looking at the OSPF RIB, or routing information base.
These are the routes that are going to be eligible for entry
into the routing table.
Of course, we can also verify this
by doing a show route IPv6, and we'll filter that by OSPF.
So we can see here that we are, in fact, learning OSPF routes
in our routing table for IPv6.
So, so far, everything is looking good.
So it looks like it's probably time
to go configure router two.
Router two, of course, is going to be
a very similar configuration.
Going to router OSPF.
Router ID of course, will be different.
Here we have interfaces in area 100,
which is where we will put our loopback interface.
Once again, we'll passive enable that.
Gig 0/0/0/0 also goes into area 100.
This one is point to point.
Gigabit 0/0/0/1, not point-to-point
because it's again, a multi access network.
Here we also have an area 1,000.
And in this one we have interface gig 0/0/0/2.
This one is also a point-to-point link.
That should take care of the configuration.
Let's commit the changes.
Once again, we see neighborships already coming up with routers
five, and four, and nine.
We see router one here just came up as well.
We'll verify our interfaces.
So all of our interfaces are in area 100 except for gigabit
0/0/0/2, which is in area 1,000.
And we see in the case of our multi access network that
gigabit 0/0/0/1, we've been elected as the DROther
or the DROther on that multi access segment.
Clearly, routers four and five on that segment
have already been elected as the DR and the BDR.
Let's also verify our neighbors.
We saw them all come up, but we just
want to make sure rather than just
looking at console messages.
So here we're up with router one,
router four, router five and router nine.
So this looks like all of our neighbors
are up here on router two, so this will bring us over
to router six.
So here on router six, since it's running IOS XE,
there's actually two different ways
to configure OSPF version three on IOS XE.
There's sort of the legacy way and well, the more modern way.
I'm going to show you the legacy way
first just so you've seen it in case you ever
run into it in the field.
So you understand what's going on
and understand that there's two different ways
to configure this.
And then of course, we'll back that out.
And then we'll implement the more modern way,
which is really how you should be implementing it.
Sort of the biggest reason for that is the newer way
allows you to do multi-protocol.
It allows you to do IPV4 and IPv6.
The legacy way only allows you to do IPv6
because that was the original intention of OSPF version
three.
So let's go ahead and take a look at that old way first
and then we'll jump into the new way.
So the old way was would start with IPv6 and then say router.
So instead of just saying router OSPF V31,
it's IPv6 router OSPF one.
And you don't say V3 here.
So you just hit Enter.
And then this is where you would go ahead and configure things
like your router ID and so on.
And then you go to your interfaces
and you configure this in a similar fashion.
The problem with this is since it starts off IPv6 router, that
locks us in to IPv6.
Because there is no IP router command,
it's just router OSPF one.
And if I said router OSPF one, I'd
be enabling OSPF version two.
So again, this isn't really how we want to configure it.
But just be aware that this structure
does exist in the command line.
And you can still, at least right now,
configure OSPF version three this way.
We of course, don't want to do that.
We'll take that back out.
And we'll configure it the modern way where
we say router OSPF V3 and then give it a process number.
Then we configure the router ID.
Now here the configuration is a little bit
different than IOS XR.
For example, if we want to say pass loopback 0,
we put it right here.
It's not under the loopback interface configuration.
And then we go configure the interfaces themselves.
Not much goes under the global process here on IOS XE.
So we go into interface loopback 0.
Then we just say OSPF V3.
We put in our process number.
And notice that we can now configure either IPv4 or IPv6
here.
Now, we're just going to be focusing on IPv6.
So we'll say IPv6.
But notice that IPv4 is in fact an option and this
is how you would go configure it.
And we want the loopback here to be in area 0.
We also need to configure interface gigabit one, which
also goes into area 0.
Interface gigabit two.
Gigabit two actually goes into area 200.
And it's a point to point network type.
So we see up above here that routers one and seven had
already come up as neighbors.
And we see that now router 10 has come up as a neighbor
as well.
Once again let's do some verification here on IOS XE.
So we can say show IPv6 route OSPF.
Verify the IPv6 routing table.
We see here that we have a lot of entries.
We're not going to go through every single one of them.
But generally speaking, we have routes here.
Show OSPF V3 interface brief.
We see that we have our interfaces configured properly.
Again two of our interfaces in area 0 and one of them
in area 200.
Also note that our gigabit one is a DROther interface.
Which again, would be expected because we already
saw that the other routers are configured
as the DR and the BDR here on this multi access
segment in area 0.
Of course, we can also look at our neighbors.
We already saw those come up, but there they are.
And they're all exactly as we would expect.
And we can also look at route, which
is how we see that OSPF RIB.
So again, this matches up with what
would be in the routing table.
So router six looks like it's configured properly.
As one final step, let's go ahead and configure
redistribution into OSPF V3.
For this we're actually going to go to router 10.
It has a loopback interface on it
that's not running OSPF version three,
and we can redistribute that into OSPF.
So if we do a show IPv6 interface brief here
on router 10, we have this loopback 100
that has an address of 2001 DB8 colon 100 colon colon 1.
Let's go ahead and redistribute that into OSPF version three.
So to do this of course, we simply
go into the routing process.
We'll go into our address family for IPv6.
We'll do a redistribute.
This is going to be connected.
And if we hit the question mark here,
we'll notice that this has the exact same features that we
have when we redistribute into OSPF version two.
So for example, we could tag these routes with, let's say,
a 100.
We can look at our database.
And we can see that we're now generating this type five
LSA into OSPF version three.
We see that it's very similar to one in OSPF version two.
Our advertising router is still our 32-bit router ID.
We still have things like our sequence numbers and such.
And then we have the actual prefix that's being advertised.
The 2001 colon DB8 colon 100 colon-- colon /64.
We see that it has a metric type of two as OSPF does by default.
And it also has a default metric of 20,
just like OSPF version two.
Also note that it brought along our route tag
that we put on it of 100.
Just to verify, let's go look at this on another router
outside of router 10.
We'll say, pick on router seven.
And there's two things we can look at in the database now.
The first would be we now have a type four LSA
because now we have an ASBR.
So we'll do inter-area and we see that router six, the ABR
is advertising the router ID of the ASPR router 10.
So we can see that this is working exactly the same
as a type four LSA operates in OSPF version two.
Also just to make sure we have it, let's go ahead
and check for the external, which of course, we have.
So we have that prefix now coming from router 10.
And finally, we can look at the routing table,
and we see the external type two showing up here
with our tag of 100.
So our redistribution is working exactly as it should.
And we can also see that it's exactly the same as OSPF
version two.
In this video, we jumped into the command line
and we got OSPF version three configured
both on IOS XR and IOS XE.
Those are, of course, substantially
different configurations but at the end of the day
they're also a little bit similar
that we're putting the same basic commands
on both operating systems.
It's just the formatting is a little bit
different between the two platforms.
Remember that on IOS XR all of the configuration
goes under the OSPF process.
And in IOS XE some of it goes under the global process
such as router ID and passive interfaces.
But actually enabling the process on the interfaces,
well that happens on the interfaces themselves.
We also wrapped up there by taking a look
at some redistribution and saw that it works exactly the same
as OSPF version two.
I hope this has been informative for you.
And I'd like to thank you for viewing.