Add OOMKill alert

_data/rules.yml

@@ -1546,6 +1546,10 @@ groups:
                 query: 'kube_hpa_status_desired_replicas >= kube_hpa_spec_max_replicas'
                 severity: info
                 for: 2m
+              - name: Kubernetes Pod OOM killed
+                description: Pod {{ $labels.pod }} in namespace {{ $labels.namespace }} is OOMKilled
+                query: kube_pod_container_status_last_terminated_reason{reason="OOMKilled"} > 0
+                severity: Critical
               - name: Kubernetes Pod not healthy
                 description: Pod has been in a non-ready state for longer than an hour.
                 query: 'min_over_time(sum by (namespace, pod) (kube_pod_status_phase{phase=~"Pending|Unknown|Failed"})[1h:]) > 0'