DestinationRule for Preventing Forced HTTP2 Upgrade - department-of-veterans-affairs/abd-vro GitHub Wiki

The DestinationRule k8s entity set in some of the helm deployments for our k8s applications are required because of anomalous behavior in the underlying Istio service mesh which intermittently can force an upgrade to HTTP2 traffic even for applications which only support HTTP1.

As of 02/27/23 there are no assurances made that this config option for the Istio service mesh will not be made, so we must rely on these DestinationRule entities to ensure we do not begin forcing an upgrade of HTTP protocols, preventing our applications from receiving network traffic if they do not support the HTTP2 protocol.