NTP Precheck Failure Due to the Unreliable Nature of UDP: Retry the Precheck Operation

Products

• VMware vDefend Firewall
• VMware vDefend Firewall with Advanced Threat Prevention

Issue/Introduction

When performing an NTP precheck, users may encounter occasional failures due to the inherent characteristics of the NTP protocol, which relies on UDP. Since UDP is a connectionless protocol, it does not guarantee message delivery or response, which can result in a failed precheck under certain circumstances.

Environment

SSP 5.0

Cause

The NTP protocol operates over UDP, which is an unreliable, connectionless protocol. As a result, the response from the NTP server is not always guaranteed, leading to occasional failures in the precheck operation.

Resolution

If you experience a failure during the NTP precheck, we recommend retrying the precheck operation. Since UDP does not guarantee message delivery, retrying the operation can often resolve the issue and allow the precheck to succeed.