Excessive DNS Queries Observed on vCenter 9.1

Products

• VMware vCenter Server

Issue/Introduction

An issue with the dnsmasq service exists that can sometimes lead to excessive DNS A and AAAA queries being generated in an environment. The most commonly observed symptom of this is slower DNS Server performance. 

Environment

vCenter 9.1

Cause

This is a known issue with the dnsmasq service's ability to cache a specific cookie, creating what is essentially a feedback loop of packets being marked as forgeries which leads to drops and re-submits. 

Resolution

This issue is resolved in 9.1.0.0200 and later.