"Hosts with duplicate IP issues" alert for vmk interface associated with iLO virtual NIC

Products

• VMware vSAN

Issue/Introduction

A red alarm is displayed under "vSAN Cluster - Monitor - vSAN - Skyline health - Network Health - Hosts with duplicate IP issues" with two or more hosts listing IP address "16.1.15.2" as conflicting one. 

This might be validated by logging into each listed ESXi using SSH and running: 

esxcfg-vmknic -l

...and confirming value in "IP Address" column, example:

Interface  Port Group/DVPort/Opaque Network    IP Family IP Address    Netmask         Broadcast       MAC Address       MTU     TSO MSS   Enabled Type  NetStack
:
vmk3       pgUSB                               IPv4      16.1.15.2     255.255.##.##   ##.##.##.##     00:##:##:##:##:00 1500    65535     true    DHCP  defaultTcpipStack
:

Environment

vSAN 7.x and 8.x

Cause

IP address "16.1.15.2" can sometimes be used by automation, when Virtual NIC is configured by iLO, REF: Using the Virtual NIC to access the iLO web interface

Resolution

Use "Virtual NIC to access the iLO web interface" functionality on one host at a time.

Alternatively, consider disabling the feature as described in Synergy 480 Gen10 server // ESXi 7.0.x - How to disable vusb interface in OS as well has HW level 

Additional Information

vSAN Health Service - vSAN Network Health – Hosts with duplicate IP issues