This is the third post in a series of posts providing step-by-step instructions that need to be followed in order to solve the labs proposed by Wendell Odom, the author of the books:

1. CCNA 200-301 Official Cert Guide, Volume 1

2. CCNA 200-301 Official Cert Guide, Volume 2

If you want to follow along, you can find the lab requirements and the .pkt file on Wendell’s blog.

You can download the Packet Tracer from Cisco Networking Academy.

You can find the second post here.

In this lab, we need to configure dynamic NAT (Network Address Translation) on a Cisco router.

These are the steps we need to take:

1. Identify the hosts for which dynamic network address translations should take place (In our lab these are S1, S2 and S3).
2. Configure a NAT pool on R1.
3. Configure dynamic NAT on R1.
4. Check that dynamic NAT is working as intended.

Check that the initial configuration is in place

Here is the network diagram used in this lab:

In the first step, I will check the initial configuration of the routers.

Configure the numbered access list (ACL) on router R1

In order to identify the hosts for which the address translations should take place, we need to configure a numbered access list on R1.

access-list 1 permit 10.1.1.0 0.0.0.255

Configure a NAT pool on router R1

In order to configure the NAT pool, we need to use the below command:

ip nat pool nat_pool 172.16.10.10 172.16.10.20 netmask 255.255.255.0

Configure dynamic NAT on router R1

Now, we need to configure the dynamic NAT on the Cisco router R1, and specify the inside and outside interfaces for which dynamic NAT should be performed.

ip nat inside source list 1 pool nat_pool

# under interface gig0/1
ip nat inside 

#under interface gig0/2
ip nat outside

Check that dynamic NAT is working as intended

The last step is to verify the connectivity and ensure that dynamic NAT is working as expected.

ping 172.16.10.2

Now, we need to check if there are any translations on the router R1.

show ip nat translations
show ip nat statistics
show ip access-lists 

I hope you find this post helpful.

If you struggle to configure dynamic NAT, share your issue in the comments and I will try to help you.