How to use a specific IP address from pool using NAPT-44


This article describes, how to use a specific IP address from a pool while using DIA.



Prerequisites

  1. The branch is provisioned with Direct Internet Access (DIA) using Config Template
  2. There is at least 1 IP address available in the pool to be used for DIA at the branch
  3. This document is not restricted to specific Versa certified software and hardware versions.


Use Case
Customer wants to use specific Public IP address for Internet bound traffic (local breakout)

  1. Original Source IP Address of Host on LAN segment :192.168.2.69
  2. Destination IP address: 8.8.8.8
  3. Source NAT IP address: 200.200.200.3
  4. Destination NAT IP Address: 8.8.8.8


Configuring NAT pools

  1. In the Appliance view, go to Services > CGNAT.
  2. Click + to add a pool.



 


This is the IP address that will be used for all internet bound traffic matching the criterion defined in the rule.


 



  1. Click OK.

 

The next step is to define the network address match criteria and the actions to be taken when the criteria is met.


Configuring NAT rules

  1. In the Appliance view, go to Services > CGNAT > Rules. 
  2. Click + to configure a rule.




  1. To configure the criteria to select traffic for translation, click the Match tab.




4. Click the Action tab. Define the action to be taken on the traffic that meets the matching criteria.


 

  1. Click OK.

 

Validation


You can monitor the session details and NAT Pool/Rule/usage as below.


CGNAT Pool:



CGNAT Rule:


 

Below is the session extensive CLI output for a session. 

You can find the NAT-Rule, Interfaces, source and destination IP Address.



Troubleshooting Steps

Check the session is created on FlexVNF or not.




Check the CGNAT Rule hit count.



Check the NAT Pool hit count.



Check the sessions extensive and make sure the session is hitting the specific Rule/Interfaces/NAT.