Our challenge, as you may be noticing,
is we have to issue some new commands.
This time, we are creating a new VRF called corp.
We're adding gig20 into that VRF,
and then we're running EIGRP on that interface
within that VRF.
This is being done on R4.
So if we're looking at this,
let's go ahead and look at the image.
We're saying right here on R4,
specifically, this interface going up to R2 WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
specifically, this interface going up to R2
is now in a VRF.
And the problem is when we try and do a trace route
down here to this interface,
it takes, actually, I think it takes, let me undo,
it does this path here to get to the destination.
So the question is why?
What changed here about this?
How do we verify this, and what can we do about it?
So if I give this a show IP route, WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
So if I give this a show IP route,
sure enough, I do have learned interfaces here,
and I even see 10.1.7 is here.
But the whole idea here
is this is the global routing table, right?
This is not a specific VRF.
VRFs are a virtualized, almost like a private instance
of a different routing table.
So we're not looking at that specific routing table here,
are we?
If I say show IP route, then VRF Corp, WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
If I say show IP route, then VRF Corp,
I can see the specific routing table here
and the routes that are learned
on that particular interface
and the routes that go that way.
So here I do see 10.1.7 via 10.2.4.
Compare that to the global routing table
where I see 10.1.7 via 10.0.3.4.
The same things go with EIGRP commands.
If I do show IP EIGRP interfaces, WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
If I do show IP EIGRP interfaces,
I don't even see gig 2.0 in the list.
I only see the ones that are in the global
IPv4 configuration.
To see the VRF combination,
I have to do show IP EIGRP VRF Corp, then interfaces,
and now I see my specific EIGRP instance
running within the VRF.
Same thing with EIGRP neighbor adjacencies. WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
Same thing with EIGRP neighbor adjacencies.
Oh, show IP, got to spell it correctly though.
EIGRP neighbor adjacencies.
See, I see 4.6 and 3.4,
but I don't see the 2.4 connection.
Again, we have to do show IP EIGRP VRF Corp
and then neighbor adjacencies,
and we can see the connection to that neighbor adjacency.
So ultimately, when you want to ping 10.1.7.7,
sure, I've got a route either going through the global route WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
sure, I've got a route either going through the global route
or the VRF, but which route did this take?
Well, if I do trace route 10.1.7.7 like this,
it uses the global routing table
because we didn't specify a specific VRF to use.
If I want to use a VRF,
I can say ping via the VRF Corp 10.1.7.7,
traffic goes round trip, and the same drill here,
if we do trace route, we can say use VRF Corp to 10.1.7.7, WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
if we do trace route, we can say use VRF Corp to 10.1.7.7,
and now it takes the more optimal path.
So what is the solution?
Well, it's a few solutions.
The primary one is know that you're using a VRF
because you may want to use a VRF,
and then your subsequent commands have to be directed
to use that VRF, like ping or trace route,
or your show commands.
Secondly, you may have to redesign your VRFs.
If you've got all your routes in the global routing table
and you want them in a VRF or vice versa, WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
and you want them in a VRF or vice versa,
you need to undo the configuration.
Thirdly, there's something called route leaking,
where we can actually leak routes out of the VRF
and into another one or vice versa,
and that's beyond the scope of the NRC certification exam.
So now we've taken a look at what happens
when we throw VRFs into the mix
and what we should know about that.
It's really just about knowing when to use your VRF commands
for your show commands, as well as your pings WEBVTT X-TIMESTAMP-MAP=MPEGTS:0,LOCAL:00:00:00.000
for your show commands, as well as your pings
and trace routes.