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So the next thing we want to do is test reachability out to the internet from

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subnet 10.

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We're going to do this simply by sourcing the same pings and such that we

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already did,

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but this time sourcing them from the gigabit 2 interface on the router.

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Now this may seem like a very simple thing to do, but you might find yourself a

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little

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bit surprised by the results.

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Maybe not.

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Let's jump in and find out.
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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Let's jump in and find out.

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So just as a reminder of where we are, let's do a ping of 8.8.8.8.

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And if you remember correctly from the previous video, we had no problem p

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inging this address

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at all.

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However, if we were to do the same ping and this time source it from our gig

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abit 2 interface,

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which is subnet 10, we'll find that this is not functioning.

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And the reason for this is fairly straightforward.

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The internet gateway that we're going out to the internet through will only gn
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The internet gateway that we're going out to the internet through will only gn

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at for

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packets that arrive on the correct subnet.

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So when we have a packet coming from subnet 10 being routed by AWS R1 here that

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's then

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arriving on subnet 1 at the internet gateway, the internet gateway is not going

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to gnat

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that address.

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Therefore, if we want this to function correctly, we're going to have the first

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gnat here on
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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gnat here on

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router one.

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So let's go ahead and configure that.

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The first thing we're going to need is an access list.

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And we'll just do a standard access list.

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We'll call it ACL underscore net.

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And we'll simply permit 10 dot 20 dot 10 dot zero.

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And we'll use a slash 24 based wild card mask.

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The next thing, of course, we're going to need is our gnat statement.

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So we'll do an IP net.

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Of course, we're not in the inside addresses.
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Of course, we're not in the inside addresses.

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And we're not in the source address.

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We're going to do this based on the list we just wrote.

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So ACL underscore net.

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We're going to overload on the interface gigabit one.

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Of course, we have to configure our interfaces.

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So interface gigabit one is IP net outside interface gigabit two.

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I pin that inside exit configuration.

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And let's try our ping again.
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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And let's try our ping again.

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Notice this time it's successful.

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And if we do a show IP net translation, we can see that we natted our inside

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local address

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of 10 dot 20 dot 10 dot 254 behind the inside global address of 10 dot 20 dot

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one dot 254.

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And that's why this is working.

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Now that we have not enabled on router one.

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So now that this is working, let's actually bring up some machines on subnet 10
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X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000

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So now that this is working, let's actually bring up some machines on subnet 10

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and make

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sure that those machines can also get out to the internet and that our net and

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everything

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with the routing is working properly.