If there are some k8s issues you are investigating, it’s worth checking k8s events. In the sample events below, we can see that multiple pods are encountering readiness and liveness probe issues arond the same time. By the looks of it, it looks like a cluster-wide issue.
kubectl get events -A --sort-by=.metadata.creationTimestampNAMESPACE LAST SEEN TYPE REASON OBJECT MESSAGE
kube-system 28m Warning Unhealthy pod/coredns-76f75df574-x8m2p Readiness probe failed: Get "http://192.0.2.3:8181/ready": dial tcp 192.0.2.3:8181: connect: connection refused
kube-system 28m Warning Unhealthy pod/kube-controller-manager-demo-node Liveness probe failed: Get "https://127.0.0.1:10257/healthz": dial tcp 127.0.0.1:10257: connect: connection refused
demo 28m Warning Unhealthy pod/demo-api-7d9f8c6b5-x2k4m Liveness probe failed: Get "http://192.0.2.6:8080/healthz": dial tcp 192.0.2.6:8080: connect: connection refused
messaging 28m Warning Unhealthy pod/demo-queue-0 Liveness probe failed: dial tcp 192.0.2.5:5672: connect: connection refused
database 28m Warning Unhealthy pod/demo-database-0 Liveness probe failed: dial tcp 192.0.2.4:27017: connect: connection refused
messaging 28m Warning Unhealthy pod/demo-queue-0 Readiness probe failed: dial tcp 192.0.2.5:5672: connect: connection refused
kube-system 28m Warning Unhealthy pod/kube-apiserver-demo-node Readiness probe failed: HTTP probe failed with statuscode: 500
kube-system 28m Warning Unhealthy pod/kube-apiserver-demo-node Liveness probe failed: HTTP probe failed with statuscode: 500
database 28m Warning Unhealthy pod/demo-database-0 Readiness probe failed: dial tcp 192.0.2.4:27017: connect: connection refused
default 27m Normal Starting node/demo-node
default 14m Normal Starting node/demo-node
default 6m2s Normal Starting node/demo-node