KBY Error Reference
Start with the exact code or status your system emitted. Each reviewed entry explains the boundary that produced it and the first checks that distinguish likely causes.
PostgreSQL too_many_connections
PostgreSQL rejected a new session because the server has reached its usable connection limit.
PostgreSQL deadlock_detected
PostgreSQL found a cycle of sessions waiting on one another and aborted one transaction to break it.
PostgreSQL unique_violation
An INSERT or UPDATE attempted to create a value combination already protected by a unique constraint or index.
PostgreSQL foreign_key_violation
A write would leave a child row referencing a parent key that does not exist, or a parent change would orphan dependent rows.
PostgreSQL serialization_failure
A serializable or repeatable-read transaction could not complete without violating the isolation guarantee.
PostgreSQL admin_shutdown
The server terminated the client connection because PostgreSQL was stopped, restarted, promoted, or explicitly instructed to end sessions.
PostgreSQL lock_not_available
A statement configured not to wait, or constrained by lock_timeout, could not acquire its required lock.
PostgreSQL undefined_table
PostgreSQL could not resolve a referenced table, view, sequence, materialized view, or other relation in the active namespace.
PostgreSQL invalid_password
The server selected a password-based authentication rule and could not validate the supplied credentials.
PostgreSQL connection_failure
An established PostgreSQL connection failed while the client was using it, leaving the current operation interrupted or uncertain.
Kubernetes CrashLoopBackOff
A container repeatedly starts and exits, so the kubelet applies an increasing delay before trying again.
Kubernetes ImagePullBackOff
The node cannot retrieve a container image and is delaying subsequent pull attempts.
Kubernetes OOMKilled
The container exceeded available memory at its cgroup or node boundary and was killed.
Kubernetes FailedScheduling: insufficient resources
The scheduler cannot find a node that satisfies the Pod's resource requests and placement constraints.
Kubernetes FailedMount
Kubernetes could not attach, prepare or mount one or more volumes required by the Pod.
Kubernetes RBAC forbidden
The request was authenticated, but the active authoriser did not permit the requested verb, resource and scope.
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 readiness probe connection refused
The kubelet reached the Pod network but no process accepted the readiness probe connection at the configured address and port.
Kubernetes Pod evicted by node pressure
The kubelet terminated a Pod to reclaim a constrained node resource such as memory, filesystem space or inodes.
Kubernetes Node NotReady
The control plane no longer considers a node healthy enough to host normal workload traffic.
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.
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