Host Connection with vCenter Flapping

Products

• VMware vCenter Server

Issue/Introduction

The term "flapping" in this context can mean different things to different people.  

The most common meaning would be that ESXi hosts show as "Not Responding" at times when viewed from vCenter, and after a short time, the hosts then show as normal.

The "flapping" is meant to suggest that the state changes repeatedly, with no obvious reason.

Cause

There are multiple reasons why an ESXi host can transition to a "Not Responding" state.  

 

Resolution

As a first step, follow the steps in Troubleshooting an ESXi host in a "not responding"/"disconnected" state