[MUSIC PLAYING]
So now that we have multi-protocol BGP
up and running in the core of our network,
it's now time to run a CE-PE protocol to actually get
the routes from the customers to the PE routers
so that multi-protocol BGP can then carry
those routes through the core.
Now, in this particular demonstration,
we're just going to be doing a very simple OSPF
setup as our CE-PE.
We have other skills coming up that will
cover using OSPF and other CE-PE protocols in much more detail.
So for this demonstration, we're just
going to be setting up a quick, easy example
so that we can get our MPLS Layer 3 VPNs functional.
So let's go ahead and get started.
As usual, we'll take a look at that topology first,
so we know what we're going to be running, and where.
And then we'll jump into the command line, and get this up
and working.
So what we're going to be configuring
in this demonstration, we're going
to configure Customer A to run OSPF.
And in particular, we're going to put everything into area 0.
So what we're going to do is, for the customer routers--
so that will be Router 6, Router 8 over here, and Router 9--
we're simply going to configure OSPF area
0 on all of the interfaces on those devices.
Then of course, on the PEs--
Router 1 and Router 5--
we're going to be configuring the VRFs for Customer A
to be running OSPF.
And then we're going to set up redistribution between OSPF
and BGP on both of the PE's mutual redistribution
so that our OSPF routes end up in BGP and vise versa.
So that said, let's go ahead and get started.
We'll just jump in on Router 1.
So the first thing we need to do is configure
a process for OSPF.
Here, we'll use process 100.
And then we assign this to the VRF.
So we'll say VRF Customer A. We'll go into our address
family for IPv4 unicast, into the configuration for area 0,
and we'll assign interface gig 0/0/0/0,
which is the interface facing our customer, Router 6.
And while we're in here, let's also
configure the network to be a point-to-point OSPF network
type.
We'll go ahead and commit those changes.
And we'll exit configuration for now.
Now let's go out and configure Router 6,
which is the customer side of this connection.
On the customer routers, we're going to do a very generic OSPF
configuration.
We'll just say Router OSPF 1.
We will set the router ID.
And then we'll simply use a network statement
to bring all of the interfaces on this device into area 0.
Now, we will have to go into our interface gigabyte 1
and set it to IP OSPF network type point-to-point,
since that's what we did on Router 1.
And what we see here after a slight delay of OSPF
resetting that connection when we change it to point-to-point,
we see that neighbor 10.1.1.1 on gigabit 1
went from loading to full, which means it should be operational.
Let's go see if Router 1 is actually getting the routes
from Router 6 now.
We'll just do a show IP route for VRF Customer A.
And We see that we are, in fact, getting Router 6's loopback 0
and loopback 100 interface, which is the 10.100.1.6.
So now that we have this side of our connection configured,
let's go over and configure the PE Router 5 for the other side
of the connection.
So here on Router 5, we'll create an OSPF process
for each customers' VRF.
So we'll say, router OSPF.
And we'll just use 101 as the process ID for VRF Customer A1.
Because remember, we have two VRFs
on this router for Customer A.
And then we'll do the same thing, but for A2.
We'll make this 102.
Then we'll configure our interfaces.
So we'll start with interface gigabit 2.
We'll put this in IP OSPF process 101.
Of course, in area 0.
And we'll change the IP OSPF network
type to be point-to-point.
We'll do essentially the same thing for interface gigabit 3.
But of course, this will be an OSPF process 102, still
in area 0.
And of course, we still want to change the network type
to point-to-point.
So that should take care of our configuration
so far on Router 5.
Let's go ahead and go over to Router 8 next.
Router 8 is going to be the same configuration as Router 6,
with the exception of the router ID.
So that said, we'll just go ahead
and paste this configuration.
We can see that it's already formed
a neighborship with Router 5.
And let's do the same thing for Router 9.
So again, we'll simply paste the configuration in.
We see our neighborship with Router 5 has come up.
So as we did before, let's go back to the PE, and make sure
it's learning the routes properly.
So back here on Router 5, we'll simply
do a show IP route for the VRF Customer A1.
And we see it's getting OSPF routes from the customer.
And if we look at A2, we'll see it is also getting OSPF routes
from the customer.
So OSPF is working properly between the CEs and the PEs.
So our final step is simply going
to be to redistribute between OSPF and BGP
bidirectionally on the PEs.
So that said, let's just go ahead and start on Router 1.
Let's just start under BGP.
So we're going to router BGP 100 for the VRF Customer A
into our address family IPv4 unicast.
And we'll simply say to redistribute OSPF 100.
And we'll go ahead and say to match internal, external,
and NSSA external, just so we make
sure we're including any possible routes
the customer can send to us.
Then we'll go into our router OSPF process.
Again, into the VRF for Customer A.
And we'll say to redistribute BGP 100.
We'll commit our changes and exit out of configuration.
Let's go do the same thing on Router 5.
Of course, the syntax here is going to be different.
So we'll go into configuration mode.
We'll start with router OSPF 101.
We'll say to redistribute BGP 100.
Then we'll go into router OSPF 102,
and we'll say the same thing.
So that takes care of redistributing the BGP
into OSPF.
Now let's go into router BGP 100.
Then we'll go into the address family for IPv4
for the VRF Customer A1.
And we say to redistribute OSPF 101.
And once again, we'll put on the match
external, internal, and NSSA external.
Next, we'll go to the address family
for IPv4 for Customer A2.
And we'll use the same redistribution line.
We just, of course, have to change the OSPF process to be
VRF Customer A2's OSPF process.
We'll go ahead and exit configuration.
And then let's go out to the customer routers
and verify that this is working.
So on Router 6, let's just do a show IP route.
And we see that we're actually getting
a whole lot of OSPF routes, which
look like the routes coming from the other side.
Let's verify Router 8.
We'll do a show IP route here as well.
Once again, we see some OSPF routes coming from Router 6.
And we should see the same thing on Router 9.
And again, we see some Router 6 routes showing up here
on Router 9.
So this certainly looks like it's working.
Let's see if we're actually getting traffic
through our environment.
Let's go back over to Router 6.
And let's just try to ping the loopback 100
interface on Router 8.
So that would be 10.100.10.8.
And we'll source that from our loopback 100 interface.
And we can see this is successful.
Let's see if we can ping Router 9 as well.
That is on a different subnet and a different IP address.
But we can see that that is also successful.
So we have connectivity between our customers
through our Layer 3 VPN.
So in this video, we finished what's
pretty much our last step to get our Layer 3 VPN up
and running, which is to put in some form of a CE-PE protocol.
Now, of course, in this demonstration,
we just did Customer A, and we just did a very simple OSPF
implementation.
Again, we'll be digging into this more
in some future skills.
But to wrap up this skill, let's take a closer look
at the traffic that's actually going between the customer
routers.
We're going to do that in the next video.
Until then, I hope this has been informative for you,
and I'd like to thank you for viewing.