Edge configured with IPv6 interfaces and/or IPv4 interfaces which also do not have next-hop Gateway settings may experience a failure of IPv4 NTP communication

Products

• VMWare SD-WAN

Issue/Introduction

IPv4 NTP communication may fail if an SD-WAN Edge's routed interfaces are either an IPv6 address (regardless of whether or not the Gateway is set), or an IPv4 address with an empty Gateway setting. This can occur regardless of whether or not there is an IPv4 VLAN setting or loopback interface. A routed interface with an IPv4 address and a Gateway setting is required for IPv4 NTP communication to succeed.

The image below is an example of an interface setting that can cause the NTP communication issue.
As GE3 does not have a Gateway setting, IPv4 NTP communication will not go through:

Environment

4.x, 5.x

Resolution

The following example demonstrates a correct interface configuration. Configuring a Gateway on GE3 enables NTP traffic to flow.