Mar 12 18:52:24.937 - 58s E namespace/openshift-kube-apiserver alert/KubeAPIErrorBudgetBurn alertstate/firing severity/critical ALERTS
{alertname="KubeAPIErrorBudgetBurn", alertstate="firing", long="1h", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="critical", short="5m"}

We have many guards making sure that there are always at least two instances of the kube-apiserver. If we ever reach a single kube-apiserver and it causes disruption for the clients, other alerts such as KubeAPIErrorBudgetBurn will fire.
KubeAPIDown is here to make sure that Prometheus and really any client can reach the kube-apiserver, which they can even when there is only one instance of kube-apiserver running. If they can't or that availability is disrupted, `KubeAPIErrorBudgetBurn` will fire.
Comment 23058588 by Marcel Härri at 2023-09-19T06:57:07.949+0000

# [bz-kube-apiserver][invariant] alert/KubeAPIErrorBudgetBurn should not be at or above pending
KubeAPIErrorBudgetBurn was at or above pending for at least 30m58s on platformidentification.JobType{Release:"4.13", FromRelease:"4.12", Platform:"gcp", Architecture:"amd64", Network:"sdn", Topology:"ha"} (maxAllowed=0s): pending for 30m58s, firing for 0s:
Apr 26 02:18:25.979 - 30s   I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="1d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="2h"}
Apr 26 02:18:25.979 - 1650s I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}
Apr 26 02:47:27.979 - 178s  I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}

# [bz-kube-apiserver][invariant] alert/KubeAPIErrorBudgetBurn should not be at or above pending
KubeAPIErrorBudgetBurn was at or above pending for at least 2m38s on platformidentification.JobType{Release:"4.13", FromRelease:"4.12", Platform:"gcp", Architecture:"amd64", Network:"sdn", Topology:"ha"} (maxAllowed=0s): pending for 2m38s, firing for 0s:
Apr 24 17:45:39.703 - 70s   I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}
Apr 24 17:48:21.703 - 88s   I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}

# [bz-kube-apiserver][invariant] alert/KubeAPIErrorBudgetBurn should not be at or above pending
KubeAPIErrorBudgetBurn was at or above pending for at least 1h3m34s on platformidentification.JobType{Release:"4.13", FromRelease:"4.12", Platform:"gcp", Architecture:"amd64", Network:"sdn", Topology:"ha"} (maxAllowed=0s): pending for 1h3m34s, firing for 0s:
Apr 23 10:04:01.945 I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="6h", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="critical", short="30m"}
Apr 23 10:04:01.945 - 708s  I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="1d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="2h"}
Apr 23 10:04:01.945 - 3078s I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}
Apr 23 10:57:51.945 - 28s   I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}

# [bz-kube-apiserver][invariant] alert/KubeAPIErrorBudgetBurn should not be at or above pending
KubeAPIErrorBudgetBurn was at or above pending for at least 58m28s on platformidentification.JobType{Release:"4.13", FromRelease:"4.12", Platform:"gcp", Architecture:"amd64", Network:"sdn", Topology:"ha"} (maxAllowed=0s): pending for 58m28s, firing for 0s:
Apr 20 14:11:36.753 - 256s  I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="1d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="2h"}
Apr 20 14:11:36.753 - 2986s I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}
Apr 20 14:16:24.753 - 28s   I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="1d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="2h"}
Apr 20 15:03:54.753 - 238s  I alert/KubeAPIErrorBudgetBurn ns/openshift-kube-apiserver ALERTS{alertname="KubeAPIErrorBudgetBurn", alertstate="pending", long="3d", namespace="openshift-kube-apiserver", prometheus="openshift-monitoring/k8s", severity="warning", short="6h"}