[MUSIC PLAYING]
The first thing that we want to configure
when setting up segment-routing traffic engineering
is to configure MPLS in the core to support traffic
engineering as well, because again,
remember that MPLS is the data plane for segment routing.
So what we're going to do in this video
is configure MPLS traffic engineering
on all of our devices and then configure
the core IGPs to also support MPLS traffic engineering.
So let's go ahead and bring up our topology.
This is going to be a different topology than we've
used so far, because we're going to do
all of this in a multi-domain environment being linked
together through a BGP controller.
So let's take a look at that diagram
and see where we're going to be enabling MPLS traffic
engineering so we can get ready for our segment-routing traffic
engineering tunnels and policies to be implemented.
So for this skill, we're going to be using MPLS topology 5.
Now, as we go into this, the physical connections
between all of the devices are the same.
We're just sort of modifying how they are logically connected.
So as you can see, we're going to be using
two different domains here.
We have domain 1, which is going to be running ISIS,
and we have domain 2, which is running OSPF.
Now, the IGPs are already configured.
Also keep in mind that routers 3 and 4,
although they are part of both domains,
they are not doing any redistribution.
So as of right now, domain 1 and domain 2
are completely separate.
So what we're going to be doing in this demonstration
is we're going to be configuring traffic engineering for MPLS,
both on the devices and in the IGPs.
So that said, let's go ahead and get
started, and since we have to configure all of these devices,
we'll just go ahead and start on router 1.
So we're going to start by enabling MPLS traffic
engineering, but keep in mind that, much like we didn't use
LDP when doing, we'll call it normal segment routing, when
we're doing segment-routing traffic engineering,
we also don't use RSVP like we did for traditional MPLS
traffic engineering.
So notice as we're going to go through here
and configure all of this that we're not
going to be configuring RSVP in our environment.
So again, just keep that in mind as we
go through this configuration.
So what we do have to configure is MPLS traffic engineering,
then we have to enable it on our interfaces.
So this is going to be all the interfaces on router 1.
Commit those changes, exit configuration,
and let's do a show MPLS interface.
We see here that all of those interfaces
are now enabled for tunneling.
So router 1 looks good.
Let's just go ahead and move right along to router 2.
Keep in mind that if we do our show MPLS interface
too quickly after configuring, it may not quite
be prepared yet.
So if that's the case, just wait a few seconds,
do the command again, and we see here
that now the interfaces are showing up,
and they are enabled for tunneling.
So routers 3 and 4 are, of course,
going to be very similar to routers 1 and 2,
since they're iOS XR.
Let's just go ahead and paste the configuration
on those two routers.
So that should take care of the configuration,
but we do still want to verify as we go.
So we'll do our show MPLS interface.
So all of these interfaces are good.
Let's go to router 4.
So that takes care of router 4.
And once again, show MPLS interface,
and these interfaces are correct as well.
Now, let's go over to iOS XE on router 5.
So the configuration on router 5 is simply going to be we
have to do MPLS traffic engineering tunnels
under global configuration.
Then we go into each interface.
So in this case, it's interface gigabit 1,
and we literally just put the same command
under each interface.
So this is going to be gigabit 1, gigabit 2, gigabit 3,
and gigabit 4.
We'll go ahead and exit configuration.
And again, show MPLS interface.
So here, we see those interfaces are up and ready to do tunnels.
Let's go ahead to router 6.
So one more time.
It's MPLS traffic engineering tunnels,
then we go into the interfaces, and it's the same command.
So that's gig 2, 3, and 4.
Here on router 6, just like router 5.
Now, we still have to configure routers 7 and 8.
Just like 5 and 6, they're iOS XE.
So the interfaces are a little different,
but we'll just go ahead and paste the configuration
onto those routers.
So there's router 7.
We'll do our show MPLS interface,
and we see that its two interfaces are
ready for tunnels and router 8.
So that takes care of router 8, and its interfaces
are operational as well.
So now our next step is going to be
to configure our core IGPs to support MPLS traffic
engineering tunnels.
So once again, let's just hop back over
to router 1, start there, and go through these in order.
So router 1 is in the ISIS domain.
So it's router ISIS 1.
We go into our address family for IPv4 unicast.
We go into MPLS traffic engineering,
and these are all running level 2,
so we'll just do level 2 only.
Let's also configure a router ID.
We'll just assign that to loopback 0.
Commit the changes, and exit configuration.
So now let's do a show ISIS, MPLS, traffic engineering,
advertisements.
So we can just look at this one entry here,
and the important thing to note is
look how this is carrying the exact same information
that RSVP would carry.
Yes, we have our system ID, our interface IP address,
and our neighbor's IP address.
But more importantly, look at this traffic engineering
information right here.
We have the TE metric, which is defaulting to 10.
We have our physical bandwidth, our reservable bandwidth,
and our reservable sub.
So we can see here that there's no reservations yet.
Everything is, of course, wide open.
There are 0 kilobits per second reserved.
We can see that all of the bandwidth
is unreserved at this point, but again the most important thing
to note here is how this is carrying
the exact same information as RSVP would.
This is the replacement control plane for RSVP.
So let's go ahead and configure router 2.
This is also running ISIS.
So we'll put in the same configuration,
commit the changes, exit, and verify our advertisements.
So once again, we see here router
2 advertising, essentially the same information
as router 1 was, but the point is,
again, this is replacing RSVP.
So now, let's go over to router 3.
Now, router 3 we're going to partially copy and paste,
because we've seen the ISIS configuration a few times now.
This is the same as routers 1 and 2.
But router 3 is also running router OSPF 1.
So we have to enable it here too.
This command is MPLS traffic engineering,
and let's start with our router ID here of loopback 0,
then we go into area 0 and actually enable MPLS traffic
engineering here.
Now, we can commit all of those changes,
exit configuration, and let's do a verification of ISIS again.
So we see here that router 3 is properly
advertising its information.
But let's also look at show OSPF MPLS traffic engineering link.
Here, we can see that this same information
is being sent into OSPF.
So again, we see the link ID, the interface, neighbors,
and addresses, and then we go into the admin metrics.
Now, in this case, the TE metric is actually 1,
then we see the maximum bandwidth,
the maximum global pool reservable
bandwidth, the current priority, and of course,
the current unreserved bandwidth, and so on.
But again, all of the RSVP information being
carried in OSPF.
Now, router 4 is going to have the same configuration
as router 3, so again, we can paste that configuration
in on router 4.
So there's router 4's configuration.
We'll verify our show commands there's
our ISIS advertisement and OSPF.
So that takes care of our iOS XR configuration for both ISIS
and OSPF.
So of course, now we have to move on to iOS XE.
We'll go ahead and start on router 5.
So router 5 is also part of the OSPF domain.
We turn on MPLS, traffic engineering.
We'll again set the router ID to loopback 0, enable it
for area 0.
For verification, let's do a show IP OSPF, MPLS traffic
engineering link.
So here, we're seeing the entries for router 5,
and we see that it's putting the information into OSPF,
as it should be.
So now, let's configure the rest of our routers.
Router 6 is also part of OSPF, so let's go ahead and just
paste that configuration in since it's
the same as router 5.
So that takes care of router 6's configuration.
Router 7 is going to be a little bit
different because it's in ISIS, so let's go over to router 7.
So here, we simply go into the router ISIS 1 process,
and it's almost the same commands.
It's MPLS traffic engineering.
We'll again set the router ID to loopback 0,
and instead of assigning it to an area like we did with OSPF,
what we do here is we tell it what level to use.
Again, these are all level 2 devices in this topology.
So we'll simply say level 2, exit configuration,
and let's verify.
So show ISIS, MPLS, traffic engineering, advertisements.
And we see it's advertising its information into ISIS,
as it should.
So this is working properly.
Finally, we have router 8.
Router 8 is also running OSPF, so this
is going to be the same configuration
as the other routers running OSPF and iOS XE.
We'll just paste that configuration in.
And that takes care of router 8's configuration.
We'll verify this last router, so show
IP OSPF, MPLS traffic engineering link.
And we see it's advertising its information as it should.
So now, our IPs are properly configured
for traffic engineering.
So in this video, we saw how to enable MPLS traffic
engineering, both on our devices and interfaces and in our IGPs,
including ISIS and OSPF.
Of course, we also looked at this on both iOS XE and iOS XR.
The big takeaway here is we don't use RSVP.
All of the information that was normally
carried in RSVP for traffic engineering
is now carried in our RGPs just like they were
updated for segment routing.
Well, they were updated for segment
routing traffic engineering as well,
so this takes care of both sides.
So now that that's configured our next step
is going to be to set up actual segment routing in our core
since that's not yet configured.
But that's what we're going to do next.
But until then, I hope this has been informative for you,
and I'd like to thank you for viewing.