This is one of multiple videos discussing network address, translation or net.
In this scenario, we've been told that devices on the inside of our network, such as Router one,
acting as PC one root of four acting as PC two and rather five acting as PC three are not able to ping
Google.
In other words, 828.8.8.
In this topology, router three is configured as Google.
So let's do some verification.
Here's rather one acting as PC one at the top.
Can it ping?
828.8.8.
As we can see in the output, it's not able to ping the Google address.
Show IP route.
We do have a static default route to ten 11254, which is the IP address of router two acting as our
net router.
So let's do a trace to 8.8.8 to date to speed things up.
I'll type no IP domain lookup.
Do that again.
So we hit the default gateway, but we don't go any further.
Just do that again.
So trace to 8.828.8.
It gets to the default gateway, which is rather two but doesn't get any further.
So can rather to ping google paying 8.828.8.
Yes, it can.
It can ping the google IP address of quadruple eight.
This is our net router.
So let's do some net debug.
So debug ip net.
Press enter.
Net debugging is now enabled.
Ping from rota one to google.
We not getting any output in the net debug show ip net translations.
There are no net translations.
Show IP net statistics.
Okay.
So can you find the problem?
Can you see where the issue is in this output?
Notice here.
Total active translations is zero.
We had peak translations previously of two.
And here's the problem.
There are no outside interfaces.
There are only inside interfaces.
Gigabyte 000102 and zero three are configured as inside interfaces.
Looking at rather two's interfaces.
That's incorrect.
This interface gigabyte is zero one is on the outside.
In other words, it's connected to the internet.
These three interfaces are on the inside.
In other words, they are on the local LAN and they should be netted.
So before I do a change, let's look at the config.
This interface is inside according to the configuration.
This interface is the inside according to the config, but according to the topology that should be
the outside.
So that's wrong.
Other interfaces are configured correctly as the inside interface, but we need to change gigabit zero
one and make that the outside interface.
Notice the problem.
When I hit Enter we told that it's inside.
So no IP net inside.
IP net outside.
So we've made it the outside interface now.
Show IP.
Net statistics shows us that gigabit is there.
One is the outside.
These three interfaces are inside interfaces.
So in of one, can we ping Google?
Yes, we can.
We can see the net translations on rather too.
So source IP address of ten 111 was translated to 828.8254 destination being Google.
We got the reply back and the reply was translated, so that looks good.
What about rate of four and root of five acting as internal hosts?
Ping 8.8.8.8.
Ping succeeds of five.
Ping 8.8.8.8 Ping succeeds.
So we've resolved the network address translation issue in this topology.
Don't forget, you need to configure inside and outside interfaces correctly when configuring network
address translation.
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I wish you all the very best.