This is one of multiple network address translation or not to trouble shooting videos in this typology
we've been told that hosts on the inside network rodder one acting as host one writer for acting as
host two and write a five acting as host three are not able to paying wrote a three acting as Google
wrote a tuneless typologies configured as the NAT router so let's do some verification on brought a
one to one able to ping the Google Server 8 8 8 8 and at the moment it's not let's do a debug on route
to acting as on NAT router so debug IP not do the ping again.
We are not getting any output on the console and we are monitoring debugs on the console at the moment
so let's verify that traffic is getting to the default gateway.
In this example the Rodda has a default gateway of 10 dot wandered wondered too far for a ping tendered
one would want to fight for traffic gets to the default gateway.
Let's trace to Google dot com.
Traffic gets to the default gateway which is Rodda to.
In this example
it gets no further.
So the Trace's timing out so let's determine if the problem is on the net to rodder.
So show IP net statistics shows us statistics of the net configuration.
Here's the command.
We don't have any active translations.
The outside interfaces gigabit is 0 1 which is correct.
Per our diagram inside interfaces are gigabit to 0 0 0 2 0 3 which is correct.
Per our diagram we have a dynamic translation configured for inside source addresses.
We're using access list one and a Nat Poole called Net pool which has this Sublette mosque and this
range of addresses.
So let's do some more investigation show run pipe include Nat.
These are the commands on the various interfaces.
We were able to see which interfaces had not configured through this output here.
So we know that some interfaces are configured as inside and one is configured as outside.
And that's what this config is showing.
You could if you wanted to make sure use commands such a show run interface and a individually interface
such as gigabit 0 or 1 to confirm that the match has being configured correctly on the interface.
But the statistics command has shown us that output is ready to show run pipe including that we can
see here that a net command is being configured netting inside source addresses using access list 1.
And in fact Paul called Net pool which is configured here and we can see a range of addresses in the
pool and a subnet mask show access lists.
We've got access list one configured and that's what's being referenced in the next statement.
And we have some matches in the access list show IP interface brief.
Can you see the problem.
Let's have a look at Rotto for sure.
I've been to face brief.
Can you see the problem here let me give you another hint.
Show interface give it a 0 0 show.
Bruhn interface.
Give it to 00 and on Rotto for a show run interface gigabit 00.
Can you see the problem is another hint to show run pipe include access look at how this access list
is configured.
Compare that to the IP addresses of the host devices.
OK so notice this host is in subnet 10 1 2 0.
This host is in subnet 10 1 1 0 slushed 24 mosque here.
However the access list is matching 10 is 0 1 10 0 2 and 10 0 3 host 5 acting as our third internal
PC has an IP address 10 1 3 3 slushed 24 the sexist list is incorrect.
So no access list one access list 1 permit 10 1 1 0 slushed 24 10 1 2 0 Slide 24 10 1 3 0 slash 24.
So show access list this access list looks better.
Let's confirm that networks are paying 8 8 8 8 Ping's succeeds.
We see the net translations on Route 2 for that host peing 8 8 8 8 Ping's succeed and we see the net
translations and on five of those internal host Ping's succeed and we see the net translations.
So be careful with your access lists your access lists hefty match your data statements and be correct
for the hosts in the typology this net statement is matching X-ists list one access list one is now
correctly configured.
So we see matches on the access list.
That was an example of troubleshooting Network Address Translation.
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