Duplicate IP issue observed when static IP is assigned for service type loadbalancer from the Floating IP Pool

Products

• VMware Cloud PKS

Issue/Introduction

Symptoms:

• A user assigns a static IP to service type loadbalancer from the Floating IP Pool
• The same IP get reused by NCP when another service is created 
• Issue is not seen if the IP is dynamically assigned to the kubernetes service

Environment

VMware PKS 1.x

Cause

The issue occurs as the IP does not get added to allocated IP list in the Floating IP Pool if the loadbalancer IP is updated explicitly in the service deployment file.

Resolution

This is an expected behavior.

Assigning static IP is not the standard way to consume a kubernetes service of type LB with PKS/NSX-T. NCP is the main component and user should use the dynamic IP (picked from PKS floating IP pool) assigned to the kubernetes service. Forcing this IP to a desired value is not supported. 

Additional Information

Impact/Risks:
Since the IP is not added to allocated IP list, the same IP may get used for any other service like SNAT created by NCP leading to a duplicate IP issue.