In the previous video, we have done configuring default route on router 3. 2
Next in this video, we are going to configure nat so all client will able to ping to internet. Okay let’s just start. 3
To configure nat, first we need to define the private ip address 4
using access list. In this case, the private ip address is vlan 10 and vlan 20, 5
Let’s create the access list, access-list 1 permit 192.168.10.0 6
0.0.0.255, this is for vlan 10, next let’s also create for vlan 20, 7
Access-list 1 permit 192.168.20.0 0.0.0.255. 8
Next, to configure nat, the command is ip nat inside source list 1 9
interface this is the public interface, which is fa0/0, and then overload. 10
This command means, that the router will doing a nat from list 1, list 1 is vlan 10 and vlan 20, 11
so vlan 10 and vlan 20 will be translated to the ip address of fa0/0. In this case 10.20.20.2. 12
so now if the client go to internet, the original source address is 192.168.10.2, 13
but after pass the router, the source address will be translated to 10.20.20.2 14
and then overload means that many private ip address will be translated to only one 15
public ip address, here we can see that we have many client with private ip address, 16
but we only have 1 public ip address. 17
So we need to use overload here, to translate many private ip address become 1 public ip address. 18
Next we need to define all of interface become nat inside or nat outside. 19
Let’s start with fa0/0, so interface fa0/0 20
This interface is connected to the internet, so this will be nat outside, so here ip nat outside. 21
Next, go to sub interface for vlan 10, interface fa0/1.10, this interface is connected to internal, 22
so we need to define this interface become nat inside, the command is ip nat inside. 23
Let’s also define sub interface for vlan 20 as nat inside, interface fa0/1.20, ip nat inside. 24
Okay we have done configuring nat. 25
Now let’s try ping from client to internet or google, pc0 to gooogle, okay this is success. 26
Let’s also test from vlan 20, ping 172.16.10.2, okay this is also success. 27
Okay so now we have done configuring nat. 28
I think enough for this video 29
Thank you for watching and see you on the next video .