So with this game plan in mind, our first step is to go ahead and implement
static net on our four.
And let's do that to map the address 1030.51, which is the IP address of PC30
right here,
over to 23.1.2.51. Also, before we set up the net rules here and specify these
interfaces as inside
or outside, I also want to take a moment and just verify it from PC30, then it
actually can ping 23.1.2.4,
the interface address here on gig 2.0. That will guarantee us that we have
reachability back from WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
reachability back from
R4, the net device back to PC30. So let's do that first to verify connectivity
and then we'll set up
our static net rule. So here in the lab environment, let me go ahead and double
click on our lab
topology to go ahead and open it up. Fantastic. There it is. Let me scooch this
down just a little bit.
Next, let's select server one -nug and with this selected, we'll double click
on that to open that
up. And that's where we're going to get console access to each of our devices
in our topology. So we'll
give that a moment to open up and here it comes. Fantastic. So first, let's go
to PC30, which is right here. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
to PC30, which is right here.
And from PC30, I just want to validate that we can reach 23.1.2.4, which is the
gig 2.0
interface address up on R4. So we can verify that also on R4 by doing a show IP
interface brief.
And sure enough, gig 2.0 has that IP address right there. So we'll go ahead and
just copy that address.
And we'll go back to PC30 by clicking on the PC30 tab. And let's do a ping and
paste in that address
and press enter. And sure enough, we have connectivity up to R4. So here in R4, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
and press enter. And sure enough, we have connectivity up to R4. So here in R4,
before we set up
the static net with a single IP address mapped to 1030-051, we also need to
specify which interfaces
on R4 are going to be inside interfaces, which is going to be FA4/1 and gig 1.0
. And which interface
is going to be the outside interface and that's gig 2.0. So we'll go ahead and
make that configuration
next. So we'll go to the right device. So that's R4 and we'll go to
configuration mode, go to
interface, not Gaff or /1, but FA4/1. And we'll say IP_NAT inside, just like WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
interface, not Gaff or /1, but FA4/1. And we'll say IP_NAT inside, just like
that. And then we'll go to
interface_GIG 1/0. And it's also an inside interface with IP_NAT inside. And
behind the scenes,
this creates this virtual interface is going to be using as part of the address
translation. And we
have one more interface and that is the interface_GIG 2.0, which is just
confirm the interface here.
So interface_GIG 2.0 is the interface on R4 facing out towards the internet.
And that's going to be our
outside interface. So we'll go to interface_GIG 2/0 and specify IP_NAT outside.
And then we can
verify our work by doing a show IP_NAT statistics. So here in the output of WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
verify our work by doing a show IP_NAT statistics. So here in the output of
show IP_NAT statistics, it lets us
know exactly which interfaces are outside interfaces. In this case, gig 2.0 and
which interfaces are inside
interfaces, including GIG 1/0 and also fast-eaten at 4/1. So so far, so good.
Let's look at our game plan.
So now that we have labeled these interfaces, next, let's go ahead and specify
that we want a static
mapping for inside source_NAT from 1030-051, which is PC30's address, 223.1.2.
51. So here on R4, we'll go WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
51. So here on R4, we'll go
into configuration mode, and we'll type in IP_NAT inside source_Static because
we're doing static mapping.
And we want first the internal address, the inside local address of PC30, which
is, let's take a look at
our graphics here, we have 10.30.0.51. So we'll put that in 10.30.0.51 space,
and then the address that we want
to translate that to, which is going to be, and based on our game plan, that's
going to be 23.1.2.51. So we'll put that in 23.1.2.51 for a center, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
going to be 23.1.2.51. So we'll put that in 23.1.2.51 for a center,
and then we'll actually configuration mode, let's do a show IP_NAT translation.
So now with a static mapping
like that, we don't have to have any traffic from that client going through
that router to make the
translation. That static NAT is right there. There's the hard-coded mapping
between the inside local
address 1030-051, and the source address that it's going to use as that traffic
is sent out to the
Internet. So let's test it. Let's go to PC30, and what I like to do is from PC
30, which is right here,
let's go ahead and let's do a ping out to the server at 23.1.2.100, and if the WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
let's go ahead and let's do a ping out to the server at 23.1.2.100, and if the
response comes back,
that implies that the NAT's working because the server does not have a default
gateway that goes
back to R4. So let's do a ping, and that would use ICMP, and let's also do a
trace, and by default,
the trace is going to be using UDP. So let's go ahead and generate some traffic
from PC30 up to the
server, and then we can look at the resulting NAT translations here on R4. And
here at PC30, let's do a
ping to 23.1.2.100, and let's also go ahead and do a trace. And by default, the WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
ping to 23.1.2.100, and let's also go ahead and do a trace. And by default, the
little trace command
here on this little virtual PC is going to use UDP by default. So let's do a
trace to 23.1.2.100,
and if we want to, we can also swap out the protocol. So if we want to go ahead
and say -p,
and let's go ahead and use 6, that's TCP, they'll do the same trace, but use
TCP at layer 4. So let's go
back to R4, and if we do a show IP NAT translations in press center, check it
out. There's our static mapping
that hasn't changed, and we should have some ICMP that was from our ping, and WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
that hasn't changed, and we should have some ICMP that was from our ping, and
we should have some UDP
that was from our initial trace, and then when we change the protocol to TCP,
there's our TCP
session right there. All using that mapping from 10.30.0.51, which is the
inside local address,
the real address of the PC30, and the map address of 23.1.2.51. And notice here
that
the router, because we're doing NAT, 1 to 1 mapping at layer 3, it left the
original port. So the client
for this session used source port 55905, and as that went out towards the
server, it maintained WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
server, it maintained
that same initial source port of 55905. And with NAT, 1 to 1 mapping, we're not
going to be messing
with the layer 4 ports, because every inside address has its own global map
address at layer 3.
All right, so now that we've implemented a static NAT between one inside host,
going to the outside
world in the next video, I'd like to begin the preparation for doing dynamic N
AT and dynamic
path, and that's going to begin by creating access control lists that identify
the traffic
that is allowed to be translated. So we'll set up those ACLs in the next video, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
that is allowed to be translated. So we'll set up those ACLs in the next video,
and I'll see you there