So here's the Estrada.
Show IP interface brief.
No IP address is configured on this interface.
So interface gigabit 00/1 IP address DHCP.
I'll save the config.
Notice the writer has been assigned an IP address through DHCP.
So show IP interface brief.
Radha has got this IP address.
So can the router ping google 82.82.8.8.
Yes it can.
Can it ping cisco dot com?
And the answer is yes, it can.
It's been allocated a default route to the Internet.
Through DHCP and it can ping swisscom because it's been told the DNS server through DHCP.
But what we now need to do is configure Nat on the router to allow devices on the internal network to
access the internet.
So to do that, I'm going to configure gigabyte zero, slash zero, slash one as the outside NAT interface
and gigabit 00/0 as the Nat inside interface.
And then we need to use the command IP net inside source list.
We're going to point it to an access list, access list one and we're going to NAT all traffic to interface
gigabit is 001 and we're going to overload it.
Don't forget to enable overloading or pat and then I'm going to create an access list, one which will
permit all traffic.
So anyone in the internal network will be netted.
You could limit that in the exam.
Read carefully to see what they ask you to net.
They may say only net the subnet or net another subnet.
So be careful which subnets they tell you to net.
On PC one.
I previously configured this PC to use Google as the DNS server.
So can we ping Cisco qcom.
It's taking its time.
Doesn't look like it at the moment.
So let's test connectivity.
On coal to.
So what I'll do on code two is configure IP domain lookup.
And I'll specify the name server as Google.
Show IP rant.
We don't have a default route.
So we can't ping the Internet.
But back on the Estrada.
We can inject a default route now on OSPF and other routing protocols.
You would use the command default information originate, but configuring default gateways in air copy
can be a bit more complex.
It's out of the scope of the CCNA course, but I'm going to show it to you here so that you can see
how to inject a default route into the network.
We need to do that because the two core switches don't know how to get to the Internet.
They need to be configured to use the ISR as the default gateway.
Now the way to do this in ERP is to redistribute a default route.
We do have this route showing up that was allocated via DHCP as the route is acting as a DHCP client.
So I'm going to use the command redistribute static and I have to specify a seed metric and you can
specify sort of any values here.
But I'm going to specify.
Common values used in a lot of redistribution examples.
So show IP route on the local router shows this a default gateway.
Show IPR, GOP database or topology.
Shows us that we have that default route in the topology database.
The values that we need to specify are bandwidth delay, reliability load and empty you.
So you have to specify a seed value or a starting value for routes that are redistributed into IGP or
taken from other writing protocols into IGP.
So on, call to the call switch.
We didn't have a static default route.
We didn't have a gateway of last resort.
But now we do notice we suddenly have a default route and a gateway of last resort configured.
So previously, before we redistributed static routes, this course which didn't have a default gateway,
didn't know about a static default route, but now it does.
So can it ping the DNS server now.
Yes, it can.
Can it ping Cisco dot com?
Yes, it can.
What about on core one.
So in call one ping cisco dot com.
We need to configure a DNS server.
So firstly IP.
Domain lookup to tell the router to do domain name resolutions or domain lookups.
IP Name Server.
The DNS server that will use is Google.
So can the switch now ping cisco dot com?
Yes, it can.
That's because it's learnt the default route through ERP.
The default gateway or gateway of last resort is the ESR.
We also configured it to use domain lookup and a DNS server.
Domain lookups may be turned off in your lab or in the exam.
Make sure that you use the command IP domain lookup if required and a name server so that you can test
name resolutions.
So on PC two is an example.
Go to command prompt.
Can the pc ping cisco dot com?
Now the PC is configured with a default gateway.
So ping Cisco dot com.
It did resolve which is great.
And notice the PC can ping cisco dot com.
What about PC three?
Can it ping Cisco dot com.
We do have a DNS server configured.
It took it a while but it did resolve and it can ping Cisco dot com.
Now this is a complicated setup and there are a lot of steps to make it work.
But hopefully you've learnt a practical example of how to configure networks for the CCNA exam.
We configured many things here, we configured VLANs, we configured IP addressing, we configured HSP,
we configured ERP, we configured NAT.
This is hopefully a very comprehensive lab that has allowed you to use multiple technologies working
together to see how it actually works in a live environment.