Readiness probe failed
KubernetesWARNINGNotableContainer ErrorHIGH confidence

Pod removed from service endpoints due to failing readiness probe

Production Risk

Affected pod receives zero traffic; overall service capacity is reduced.

What this means

When the readiness probe fails, Kubernetes removes the pod from the Service's Endpoints list so it receives no traffic, but does not restart the container. This is a protective mechanism. The pod will be re-added to endpoints once the probe passes again. Unlike liveness probe failure, readiness probe failure does not cause a restart.

Why it happens
  1. 1Application is not yet ready to serve traffic (still initializing)
  2. 2Downstream dependency (database, cache) is temporarily unavailable
  3. 3Readiness endpoint path, port, or expected response is misconfigured
  4. 4Application entered a degraded state and intentionally returning non-2xx on health endpoint
How to reproduce

Pod shows Running but receives no traffic; endpoints list is empty for the service.

trigger — this will error
trigger — this will error
kubectl get endpoints myservice
# NAME        ENDPOINTS   AGE
# myservice   <none>      10m

kubectl describe pod mypod | grep -A 5 "Readiness:"
kubectl get events --field-selector involvedObject.name=mypod,reason=Unhealthy

expected output

Warning  Unhealthy  ...  Readiness probe failed: Get "http://10.0.0.5:8080/ready": connection refused

Fix 1

Check service endpoints and probe configuration

WHEN Service is not routing traffic

Check service endpoints and probe configuration
kubectl get endpoints myservice
kubectl describe pod mypod | grep -A 15 "Readiness:"

Why this works

Confirms the pod is excluded from endpoints and shows the probe configuration.

Fix 2

Verify the readiness endpoint is functional

WHEN Probe configuration looks correct

Verify the readiness endpoint is functional
kubectl exec mypod -- curl -v http://localhost:8080/ready

Why this works

Tests the readiness endpoint directly to see the actual response.

Sources
Official documentation ↗

Kubernetes Documentation

Content generated with AI assistance and reviewed for accuracy. Found an error? hello@errcodes.dev

← All Kubernetes errors