explain panic mode

Signed-off-by: Huabing Zhao <zhaohuabing@gmail.com>
zhaohuabing · Jan 2, 2025 · a7868bc · a7868bc
1 parent f71fa99
commit a7868bc
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/api/v1alpha1/healthcheck_types.go b/api/v1alpha1/healthcheck_types.go
@@ -9,6 +9,11 @@ import metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 // HealthCheck configuration to decide which endpoints
 // are healthy and can be used for routing.
+//
+// Please note that Envoy load balancer may behave differently when lots of endpoints are unhealthy because of the "panic mode".
+// When the percentage of unhealthy endpoints exceeds 50%, Envoy will disregard health status and balance across all endpoints.
+// This is called "panic mode". It's designed to prevent a situation in which host failures cascade throughout the cluster
+// as load increases.
 type HealthCheck struct {
 	// Active health check configuration
 	// +optional