[music]
OSPF, once again, we're going to be running here.
And we're going to be running this over our DMVPN cloud.
Now, we've not looked of course at the DMVPN configuration,
but it's already there, it's already set up,
I've already enumerated it.
We will get back to looking at that later.
We'll probably do it in a slightly different
topology when we do go over DMVPN.
So, really, for right now, all that really matters to us is that in
the OSPF environment here, Router 1 is our hub.
So for the sake of OSPF it's really just going to act like a NBMA network for us.
So that's the only reason I even have it there.
This is not the time to be jumping into DMVPN with IPv6,
but it's there, it's built, and it's going to act like a WAN environment
for us here for OSPF.
We're, of course, going to also run it over VLAN 344,
VLAN 24, and then over there between Routers 4 and 5 on the serial links.
We will run it over there as well,
but we will run a separate area - 45 - over there,
and then that way when we do some redistribution and this sort of
thing we'll get the chance to see all of the LSA types when we get
to looking at the database.
So let's jump in and get our Area 0 set up.
And we will be bringing all of these devices' loopbacks
into OSPF as well as we go.
Now, very similar to what we talked about in our EIGRP lesson,
OSPF version 3 - which is what you need for IPv6 -
can be configured two different ways.
There's, again, the legacy IPv6 router OSPF.
This cannot use a VRF.
I'll show you this syntax in a minute.
Then you have the newer syntax, which is router OSPFv3 X,
where, of course, in this case, X is the process number in both of these.
This is the newer method and supports VRFs.
Just like EIGRP and its two methods of being configured,
OSPF, we have this same situation with the whole VRF support
and where things are headed.
Things are headed towards router OSPFv3 and away from the IPv6 router.
So, again, most of the OSPFv3 syntax we need for when we get
to MPLS support, but, nonetheless, we will take a look at it.
And just like I did EIGRP, we'll do a mix and match
on some of the routers which ones we run.
The other nice thing too is if you use the router OSPFv3 command
you can actually run, and exchange rather, IPv4 routes over OSPF version 3.
With Legacy mode you would have, once more,
IPv6 router OSPF 1, and then you would have router OSPF 1 to run
OSPF version 2 to support IPv4 just like we've always done.
Problem is, that means you have all of this information twice.
You're essentially running two completely separate OSPF protocols.
The nice thing here - and I'm not saying anybody's going to just
jump right in this and start doing it tomorrow - but the nice thing is,
with OSPFv3 syntax that we can actually support IPv4 address family over IPv6.
So as we get our environments ready
and we start moving towards IPv6 and we fire up OSPF version 3,
it's just nice that we could - not saying that we're going to right away,
but as things progress - we can actually get rid of OSPF version 2
before we even turn off IPv4, and we can support IPv4 over OSPF version 3.
However, OSPF version 3 does still run over IPv6.
If you try to type "router OSPFv3 1" on a router,
it will yell at you that you don't have IPv6 Unicast routing enabled.
So you can't run it over IPv4 only.
So let's jump over to the command line,
and let's take a look at actually configuring this.
So on Router 1, again, we'll stick with the Legacy mode to start with here.
So on Router 1 we will say interface tunnel 0,
because that says DMVPN.
We will say, IPv6 OSPF 1 Area 0.
Now, right away we have a little bit of a danger to worry about here.
Let's do interface-- well, let's not go into the interface yet.
Let's say, do show IPv6 OSPF interface brief.
So there it is. And the problem we have is the state.
The state is point-to-point, which is going to be a problem.
Let me just show you here.
If we go to interface loopback0 and turn it into area 0--
I'm just going to fire up OSPF on the interfaces here on Routers 1, 2 and 3.
Just the routers connected to the DMVPN cloud for now.
So, interface, tunnel 0, remember that Router 1 is the hub.
Interface tunnel 0, IPv6 OSPF 1 area 0, interface loopback0, and Router 3.
And I want you to note that the tunnel process just came up with
neighbor 1.1.1.1. And if you look at Router 2,
he says the same thing, so neighbor 1.1.1.1 is up.
If you look at Routers 2 and 3, everything looks just wonderful,
but if you go to Router 1, process is full,
loading done, process is full, loading done.
Wonderful. It's all great.
Let's take a look at the routes.
Let's go to Router 2.
All he knows about is Router 1's loopback.
He doesn't know anything about Router 3.
And this is just a fundamental problem.
If I said do show IPv6 OSPF database router--
we're going to get to all the changes to the database and such in a minute.
But, see, here's an LSA from Router 3. Link connected to another
router point-to-point. That's all good,
but just to let you know, when you see things that say, "LSA ignored,"
that's really not a good thing.
The problem is, of course, we have a complete logic problem here with OSPF.
Router 1 right now sees two neighbors on a point-to-point interface,
and that's not allowed, that's not allowed.
If we were running OSPF version 2, in fact,
these neighbors would actually flap back and forth between each other.
OSPF version 3 allows the neighbors to stay up, but it's still
a logic problem in the database, and these guys just don't know how to use it.
Router 1 just happened to get Router 2's first,
so he's only believing Router 2's interface.
He's not learning anything from Router 3.
Router 3 learns nothing.
The problem is-- there you go, now you can see it's actually flapping.
We're actually not getting [console?] messages on this one,
but it's flapping them anyway.
Let's see what Router 1 is saying right now.
He says he's full with both of them, but we know better.
So, again, I'm not going to spend a whole lot of time on this,
this is just, of course, a misconfiguration.
If you're going to run-- and I'm just trying to point out that OSPF
version 3 is just like version 2 in almost every respect.
Obviously it runs over IPv6, there's been some fundamental changes
to the database we need to look at, but other than that, things like
network types, areas types, all of that stuff,
they all stay the same. So we just really have to say, interface tunnel 0.
Now, this is going to also get into a whole discussion of DMVPN,
and do we want to be running phase 1, phase 2, phase 3?
We're just going to go with phase 2 today, because I just want the
routes to get through, this is not a DMVPN discussion.
What that means is that we run OSPF network type point-to-multipoint.
So, IPv6 OSPF network point-to-multipoint.
This will be enough to get everything working.
And again, if this was a full blown OSPF discussion,
we could talk about combining point-to-multipoint with point-to-point.
You can do that.
You have to tweak the timers, of course,
because if I said do show IPv6 OSPF interface tunnel 0,
it is now point-to-multipoint and changes our timers to 30 and 120.
Again, they didn't go radically changing how OSPF works here.
And of course, Router 2.
If we leave it at point-to-point, timers are 10 and 40.
So what if I said, IPv6 OSPF--
okay, that's not what I wanted at all.
Dead interval. Seconds? About one.
Don't know what I hit up on that.
Hello interval 1. Got a little problem there.
So that's not going to be good.
This does not support minimum.
There are a couple little features here and there that we don't just
have yet, but it's okay, because hopefully you're doing BFD anyway,
so it doesn't really make any difference.
But we'll set out dead interval back to 4. We'll do 1 and 4.
[?] trying to sneak in there.
And I just configured them in a loopback... I think... on Router 2.
If anybody is familiar with the Nexus I would really love the
where command right now.
Yep. Put another loopback.
And I just typed the wrong command in there too.
Awesome.
Thank goodness for copy and paste.
It didn't take the dead interval anyway.
Because it will default to four times as much anyway.
So 1 and 4 becomes the default.
That's fine. And then Router 3, and that should come up.
Again, you can combine point-to-point and point-to-multipoint.
That's not a problem, as long as you set the timers right.
Now we should have the routes.
So, there's Router 1's loopback, Router 2's loopback.
There's Router 3's loopback, Router 1's loopback - good.
So that takes care of OSPF over the DMVPN cloud,
just running a combination of point-to-multipoint,
point-to-point, and of course, sticking with Legacy config mode,
and setting our timers.
On Router 2, let's also say, interface FA0/0 IPv6 OSPF 1 Area 0.
Router 3 is interface FA0/0.344.
And then just to show you the new syntax, we'll go to Router 4.
And this one gets a little bit different.
So interface FA0/0.24 is OSPFv3, and then you have to tell it the process ID, so 1.
Then the actual protocol, IPv6, and then Area 0.
That comes up with Router 2, and then interface FA0/0.344, same command.
So that syntax, a little bit different there.
And again, we'll mostly see this as we move into MPLS in that section.
But that's just another way to configure it.
And then interface serial 0/0/0. Same co80000 And that just turned router four into an ABR. And then over on router five, we'll just do legacy mode over here again. Interface, zero zero zero zero. IPv6 OSPF one area forty five. Interface loop back zero. In area forty five. We've done everything correctly. Let's just go over to room four to one. We'll just look the whole way furthest away. Do show IPv6 route OSPF. And we should have some O's and OIA's. There we go. There's the forty five link between routers four and five. Router five's loop back. Of course, it's doing some unequal cost load sharing or sorry, equal cost load sharing between routers two and three out of the DM VPN cloud. And that's no problem. So just as far as basic OSPF setup goes, that's it. There's not. And again, on and on with all the OSPF config, pretty much you got to get used to the new syntax with router OSPF v3. And again, we'll see more of that as we get into redistribution and MPLS and things like that. But OSPF at the end of the day is still OSPF. Area types are the same. Network types are the same. It's really just changes in the database. And we will hit those in the next lesson.