Errors in Kubernetes
- CrashLoopBackOff: Pod fails to start repeatedly.
- ImagePullBackOff: Kubernetes can’t pull the specified container image.
- ErrImagePull: Failure in pulling the image.
- Pending Pods: Pods remain in pending state due to lack of resources or node unavailability.
- Node NotReady: A node is not in a ready state, which prevents pods from running on it.
- OOMKilled: The pod gets killed because it uses more memory than allocated.
- Unauthorized: Authentication failure when trying to access resources.
- Forbidden: Authorization issue where the user does not have permissions.
- Evicted Pods: Pods are removed from a node due to resource constraints.
- PVC Bound Issues: PersistentVolumeClaims (PVCs) are not bound to PersistentVolumes (PVs).
- Service Not Accessible: Services are not reachable within or outside the cluster.
- DNS Resolution Failures: Pods cannot resolve DNS names within the cluster.
- Certificate Errors: TLS certificates are invalid or expired.
- API Server Unreachable: Cannot connect to the Kubernetes API server.
- Scheduler Failures: Pods are not being scheduled.
- Controller Manager Issues: Controllers aren’t managing resources properly.
- Network Plugin Errors: Issues with the network plugin can cause connectivity problems.
- Pod Stuck in Terminating State: Pod doesn’t terminate after issuing delete command.
- ConfigMap Not Found: Pod references a missing ConfigMap.
- Secret Not Found: Pod references a missing Secret.
- HPA Not Scaling: Horizontal Pod Autoscaler is not scaling as expected.
- Ingress Not Working: Ingress does not route traffic as expected.
- DaemonSet Pods Not Running: DaemonSet pods do not start on all nodes.
- Job Not Completing: Kubernetes Job fails to finish successfully.
- PVC Pending: PersistentVolumeClaim remains in “Pending” status.
- Node Disk Pressure: Node has high disk usage, causing evictions.
- Pod Affinity/Anti-Affinity Issues: Pods are unscheduled due to restrictive affinity rules.
- ServiceAccount Not Found: Pods reference a missing ServiceAccount.
- Node NotSchedulable: Node is marked as unschedulable, preventing pods from being placed.
- Readiness Probe Failures: Containers fail readiness checks, causing them to stay in a “Not Ready” state.
- Liveness Probe Failures: Containers fail liveness checks, resulting in restarts.
- Namespace Not Found: Resource references a non-existent namespace.
- ClusterRoleBinding Misconfiguration: Access issues due to incorrect ClusterRoleBinding setup.
- PVC Not Bound: PVC fails to bind to PV due to storage class mismatch.
- Node Memory Pressure: Nodes experience high memory pressure, causing evictions.
- Service Endpoint Not Updated: Service does not update endpoints, resulting in unreachable services.
- Endpoint Slices Issues: Endpoint slices are missing, causing network issues.
- DaemonSet Not Deploying on All Nodes: DaemonSet skips certain nodes.
- Finalizer Preventing Resource Deletion: Resource remains due to finalizers.
- Ingress 404 Errors: Requests to Ingress return 404.
- LoadBalancer IP Not Assigned: LoadBalancer service fails to get an external IP.
- HPA Targets Not Matching Metrics: HPA doesn’t scale as it’s not receiving target metrics.
- PersistentVolume Deleted but PVC Bound: PVC remains bound even though PV was deleted.
- Helm Release Fails: Helm fails due to missing charts or resources.
- API Version Deprecated: Using outdated API versions causes compatibility issues.
- Namespace Resource Quota Exceeded: Deployments fail due to resource quota limits in a namespace.
- Cannot Attach Volume to Multiple Pods: Persistent volumes with RWO access can’t be shared across pods.
- CPU Throttling: Containers experience high CPU throttling.
- Pods Evicted Due to Overcommit: Overcommitted resources lead to evictions.
- PodSecurityPolicy Issues: Pods fail to start due to restrictive PodSecurityPolicy.
Reference: 50 Kubernetes Errors & Solutions