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11 reviewed identifiers

Kubernetes errors

Exact Kubernetes error codes and states, explained from the emitting component outward. Start with evidence; follow the deeper links only when the first checks support them.

Open the Kubernetes technology index
CrashLoopBackOff

Kubernetes CrashLoopBackOff

A container repeatedly starts and exits, so the kubelet applies an increasing delay before trying again.

kubelet container restart loop
ImagePullBackOff

Kubernetes ImagePullBackOff

The node cannot retrieve a container image and is delaying subsequent pull attempts.

kubelet image manager and container runtime
OOMKilled / exit 137

Kubernetes OOMKilled

The container exceeded available memory at its cgroup or node boundary and was killed.

Linux memory cgroup and kubelet status reporting
FailedScheduling

Kubernetes FailedScheduling: insufficient resources

The scheduler cannot find a node that satisfies the Pod's resource requests and placement constraints.

kube-scheduler
FailedMount

Kubernetes FailedMount

Kubernetes could not attach, prepare or mount one or more volumes required by the Pod.

kubelet, attach/detach controller and CSI driver
HTTP 403 Forbidden

Kubernetes RBAC forbidden

The request was authenticated, but the active authoriser did not permit the requested verb, resource and scope.

Kubernetes API server authorisation
context deadline exceeded

Kubernetes context deadline exceeded

A Kubernetes operation did not complete before its caller's deadline expired, indicating latency or unavailability somewhere in the request path.

Kubernetes client, API server or downstream control-plane request
Readiness probe failed

Kubernetes readiness probe connection refused

The kubelet reached the Pod network but no process accepted the readiness probe connection at the configured address and port.

kubelet probe worker
Pod status: Failed / Reason: Evicted

Kubernetes Pod evicted by node pressure

The kubelet terminated a Pod to reclaim a constrained node resource such as memory, filesystem space or inodes.

kubelet eviction manager
NodeNotReady

Kubernetes Node NotReady

The control plane no longer considers a node healthy enough to host normal workload traffic.

node lifecycle controller and kubelet
Service has no endpoints

Kubernetes Service has no endpoints

A Kubernetes Service currently has no ready backend addresses to receive traffic, even though its virtual IP and DNS name may still exist.

Service and EndpointSlice controllers
Engineering signal

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