This is one of multiple network address translation or not videos.
This is a troubleshooting video.
In this scenario you've been told that some hosts in the internal network are not able to connect to
the Internet.
In this genus 3 typology I've got four rods broader two and rather three are acting as PCs they have
IP routing disabled.
They have the default gateways configured as Router one root of one is going to act as our network address
translation router and wrote a Foy's going to act as Google.
So let's test the network can write a one ping the DNS server Subrata for pretending to be the Google
DNS server.
Yes it can.
What about router 3.
Doesn't look like it's able to ping.
Let's investigate.
So show IP wrought we can see that IP routing is disabled on those router but it's default gateways
configured is 10 more than one.
What about on Route 2 rather 2 has the same configuration wrote it too.
Can ping 10 1 1 1 and can ping Google Rodda 3 can paying 10 1 1 1.
We could trace to Google.
It gets to its default gateway 10 1 1 1 but then nothing happens.
So we have a timeout on brought a 1 so brought a one let's confirm the IP address.
Firstly if it's zero slash one has an IP address of 10 1 1 1 that's the inside of the network.
If 0 0 has an IP address of 8 8 8 2 5 4.
So let's do it debug on this router.
Debug IP NAT router was able to pinged Google before and still can and we can see the NAT translation
taking place.
When Rotto three pings Google dot com we don't see any net translations.
Sure.
IP not translations.
So we see a net translation for Rodda too.
That's the IP address of router 2.
So show IP face brief will show us that so we can see the translation for router.
But we don't see a net translation for rodders 3.
What happens if we clear the net translations.
So there are no net translations at the moment.
We're not paying from rodded three to Google.
We suddenly see translations and the pings start succeeding sexten brought it to pain.
Google dot com
noticed it too can now no longer paying google.com.
Let's clear the net translations again.
Ratatouille is now able to pin Google's outcome
but Raanta 3 is not
so it looks like when we clear the translations one device is able to connect to google showed Bruhn
if 0 0 is correctly configured with an IP address and is configured as the outside interface.
If zero slushed one has the correct insight IP address and as configured as the inside interface OK.
Can you see the problem.
What's going on here.
Just will not play the next.
Translation a game
and then ping from router 3 which wasn't able to ping previously the pings.
Now succeed.
Show IP match translation.
We now see a net translation 4 out of three so going back through the configuration and I'll scroll
down to the net config.
Can you see the problem.
OK.
Have a look at this IP not inside source list 1 which is pointing to access list one that means that
any IP address will be netted but it's pointing to a poll called my poll the Nat Poole is configured
with a starting IP address of 8 8 8 to 2 and an ending IP address of 8 8 8 2.
That means we've only put one IP address in the poll hence only one internal host can be netted at any
given time.
So let's remove this.
We told you we can't remove it so let's clear the that translations translation install and try and
remove it again.
So it's removed now.
What we should do is add additional IP addresses to the poll Sol and from 2 to 20.
Previously it was from 8 8 8 2 2 8 8 8 to 2 but now it's going from 2 to 20.
So show run piping clewed that will show us that configuration so Ken rodders paying Google yes it can.
Ken Rodda to ping Google yes it can it took it a while but right to can ping Google router 3 can ping
Google and we see the net translations for both of them.
Notice please that the one device is not netted 2 8 8 8 3 and the other one is netted up to eight today
to today.
So show IP net translation shows us that two addresses in the pool have been used show IP not statistics
at the moment we have six dynamic translations.
Notice our poll shows us the list of IP addresses.
So we have a starting address of 8 8 today to 2 an ending of 8 8 2 8 to 20.
They are on 19 addresses in the pool and two have been allocated.
So this would be another good command to use.
Let's clear the net translation and remove the command
and add it back.
With only a single IP address in the pool it's a show IP not translations.
No translations at the moment show IP that statistics.
Notice we only have one IP address in the pool.
So when Rodda three pings
and we look at the statistics again notice 100 percent of the pool is allocated.
So that's why I wrote it to he's not able to ping because the because the pool consists of a single
IP address and it's already been allocated.
So again be careful with your polls.
You need to allocate enough addresses to the poll so clear the net translations again.
All remove that poll configure it again with let's say from 2 to 25 to show IP not statistics.
We have 24 addresses in the poll in this range.
None have been allocated Well since some traffic from both wrote to and wrote history.
So we can see that Rodda is being netted and so is Rodda three.
And now when we look at the statistics noticed 24 addresses are available to have been allocated.
So that was an example of how to troubleshoot network address translation or net hope found the video
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