Switches and VLANs: Understanding the secrets of broadcast and collision domains

In an enterprise, public network address resources are limited, while the number of internal hosts is huge. We can use the NAT address pool to dynamically map multiple internal hosts to a set of public addresses, thereby realizing a flexible and reliable network solution. Today, I will take you to set up the NAT address pool conversion on eNSP.

1. What is a NAT address pool?
Compared with Easy IP, which only uses one public IP, the NAT address pool method can flexibly define multiple public IP addresses for NAT use.

In layman's terms, I don't want to use the address on the interface as a public network IP. I have a dedicated public network address segment for you internal network hosts to use slowly.

This is also a common practice for enterprise NAT.

2. Experimental topology diagram

We build the following topology:

PC1, PC2: internal hosts
R1: border router with NAT address pool
Cloud1: connected to external network
External server: VM network (such as 192.168.248.128)

III. Specific configuration steps
1. Set R1 interface address


This completes the NAT configuration of the address pool method!

Try to ping the external 192.168.248.128, and find that the ping is successful. By capturing packets, you can see that the source address is 192.168.248.140 and the destination address is 192.168.248.128.

4. Summary of the difference between address pool and Easy IP

At this time, PC1 and PC2 cannot ping 192.168.248.128

22. Create a NAT address pool
Suppose we have a public IP resource: 192.168.248.130 - 192.168.248.140


This address segment is a "simulated public network address segment". Although it is actually a private network, it can be used as a public network resource for NAT in the VMware LAN.

3. Create an ACL to match intranet traffic

4. Set up NAT rules (using an address pool)