This article describes how to debug  'IP address validation failed' error on FortiWLC virtual instance when uploading a license file.

In Forti-WLC, system ID is coupled with IP address.
When the 'IP address validation failed' error is seen, check if the system ID resolves to the IP address of the controller.
In most of the cases, error is seen only when system ID does not resolve to FortiWLC’s IP address.

To Check the system-id on WLC:
FortiWLC# sh system-id
System Id : VENDOR_STRING= 36a3e63a65460a0e32466d3b6927be4f
To check the IP address of controller:
FortiWLC# sh ip
Interface Number IP Address        NetMask           Gateway Address Assignment Type Interface Mode
1           Static          active
        IP Addresses(1 entry)
Use Hexadecimal to IP convertor to ensure the current system ID resolves to controller’s IP address:

36a3e63a6546   0a0e3246   6d3b6927be4f  <----- Center part of system ID is what needs to be converted.

Tool to convert Hexadecimal to IP address:

With hexadecimal to IP conversion, If the system ID does not match with controller’s IP address.

- Execute setup on controller and configure the IP address statically followed by reboot of controller.
Post Controller reboot, check if System ID resolves to IP address of FortiWLC then contact Fortinet customer support to get a new license file for the current System ID.

Command to execute setup on FortiWLC:

Forti-WLC# setup