Prometheus: cannot export metrics from connected Kubernetes cluster - kubernetes

Question

The issue: I have a Prometheus outside of Kubernetes cluster. So, I want to export metrics from remote cluster.
I took the config sample from Prometheus Github repo and modified this a little bit. So, here is my jobs config.
- job_name: 'kubernetes-apiservers'
scheme: http
kubernetes_sd_configs:
- role: endpoints
api_server: http://cluster-manager.dev.example.net:8080
bearer_token_file: /opt/prometheus/prometheus/kube_tokens/dev
tls_config:
insecure_skip_verify: true
relabel_configs:
- source_labels: [__meta_kubernetes_namespace, __meta_kubernetes_service_name, __meta_kubernetes_endpoint_port_name]
action: keep
regex: default;kubernetes;http
- job_name: 'kubernetes-nodes'
scheme: http
kubernetes_sd_configs:
- role: node
api_server: http://cluster-manager.dev.example.net:8080
bearer_token_file: /opt/prometheus/prometheus/kube_tokens/dev
tls_config:
insecure_skip_verify: true
relabel_configs:
- action: labelmap
regex: __meta_kubernetes_node_label_(.+)
- job_name: 'kubernetes-service-endpoints'
scheme: http
kubernetes_sd_configs:
- role: endpoints
api_server: http://cluster-manager.dev.example.net:8080
bearer_token_file: /opt/prometheus/prometheus/kube_tokens/dev
tls_config:
insecure_skip_verify: true
relabel_configs:
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]
action: keep
regex: true
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scheme]
action: replace
target_label: __scheme__
regex: (http?)
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path]
action: replace
target_label: __metrics_path__
regex: (.+)
- source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]
action: replace
target_label: __address__
regex: (.+)(?::\d+);(\d+)
replacement: $1:$2
- action: labelmap
regex: __meta_kubernetes_service_label_(.+)
- source_labels: [__meta_kubernetes_namespace]
action: replace
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_service_name]
action: replace
target_label: kubernetes_name
- job_name: 'kubernetes-services'
scheme: http
metrics_path: /probe
params:
module: [http_2xx]
kubernetes_sd_configs:
- role: service
api_server: http://cluster-manager.dev.example.net:8080
bearer_token_file: /opt/prometheus/prometheus/kube_tokens/dev
tls_config:
insecure_skip_verify: true
relabel_configs:
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_probe]
action: keep
regex: true
- source_labels: [__address__]
target_label: __param_target
- target_label: __address__
replacement: blackbox
- source_labels: [__param_target]
target_label: instance
- action: labelmap
regex: __meta_kubernetes_service_label_(.+)
- source_labels: [__meta_kubernetes_service_namespace]
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_service_name]
target_label: kubernetes_name
- job_name: 'kubernetes-pods'
scheme: http
kubernetes_sd_configs:
- role: pod
api_server: http://cluster-manager.dev.example.net:8080
bearer_token_file: /opt/prometheus/prometheus/kube_tokens/dev
tls_config:
insecure_skip_verify: true
relabel_configs:
- source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_scrape]
action: keep
regex: true
- source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_path]
action: replace
target_label: __metrics_path__
regex: (.+)
- source_labels: [__address__, __meta_kubernetes_pod_annotation_prometheus_io_port]
action: replace
regex: (.+):(?:\d+);(\d+)
replacement: ${1}:${2}
target_label: __address__
- action: labelmap
regex: __meta_kubernetes_pod_label_(.+)
- source_labels: [__meta_kubernetes_namespace]
action: replace
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_pod_name]
action: replace
target_label: kubernetes_pod_name
I don't use a TLS connection to API, so I want to disable it.
When I curl /metrics URL from Prometheus host - it prints them.
Finally I connected to the cluster, but...the jobs are not up and therefore Prometheus doesn't expose relabeled metrics.
What I see in Console.
Targets state:
Also I checked the Prometheus debug. It's thought the system gets any necessary information and requests are done successfully.
time="2017-01-25T06:58:04Z" level=debug msg="pod update" kubernetes_sd=pod source="pod.go:66" tg="&config.TargetGroup{Targets:[]model.LabelSet{model.LabelSet{\"__meta_kubernetes_pod_container_port_protocol\":\"UDP\", \"__address__\":\"10.32.0.2:10053\", \"__meta_kubernetes_pod_container_name\":\"kube-dns\", \"__meta_kubernetes_pod_container_port_number\":\"10053\", \"__meta_kubernetes_pod_container_port_name\":\"dns-local\"}, model.LabelSet{\"__address__\":\"10.32.0.2:10053\", \"__meta_kubernetes_pod_container_name\":\"kube-dns\", \"__meta_kubernetes_pod_container_port_number\":\"10053\", \"__meta_kubernetes_pod_container_port_name\":\"dns-tcp-local\", \"__meta_kubernetes_pod_container_port_protocol\":\"TCP\"}, model.LabelSet{\"__meta_kubernetes_pod_container_name\":\"kube-dns\", \"__meta_kubernetes_pod_container_port_number\":\"10055\", \"__meta_kubernetes_pod_container_port_name\":\"metrics\", \"__meta_kubernetes_pod_container_port_protocol\":\"TCP\", \"__address__\":\"10.32.0.2:10055\"}, model.LabelSet{\"__address__\":\"10.32.0.2:53\", \"__meta_kubernetes_pod_container_name\":\"dnsmasq\", \"__meta_kubernetes_pod_container_port_number\":\"53\", \"__meta_kubernetes_pod_container_port_name\":\"dns\", \"__meta_kubernetes_pod_container_port_protocol\":\"UDP\"}, model.LabelSet{\"__address__\":\"10.32.0.2:53\", \"__meta_kubernetes_pod_container_name\":\"dnsmasq\", \"__meta_kubernetes_pod_container_port_number\":\"53\", \"__meta_kubernetes_pod_container_port_name\":\"dns-tcp\", \"__meta_kubernetes_pod_container_port_protocol\":\"TCP\"}, model.LabelSet{\"__meta_kubernetes_pod_container_port_number\":\"10054\", \"__meta_kubernetes_pod_container_port_name\":\"metrics\", \"__meta_kubernetes_pod_container_port_protocol\":\"TCP\", \"__address__\":\"10.32.0.2:10054\", \"__meta_kubernetes_pod_container_name\":\"dnsmasq-metrics\"}, model.LabelSet{\"__meta_kubernetes_pod_container_port_protocol\":\"TCP\", \"__address__\":\"10.32.0.2:8080\", \"__meta_kubernetes_pod_container_name\":\"healthz\", \"__meta_kubernetes_pod_container_port_number\":\"8080\", \"__meta_kubernetes_pod_container_port_name\":\"\"}}, Labels:model.LabelSet{\"__meta_kubernetes_pod_ready\":\"true\", \"__meta_kubernetes_pod_annotation_kubernetes_io_created_by\":\"{\\\"kind\\\":\\\"SerializedReference\\\",\\\"apiVersion\\\":\\\"v1\\\",\\\"reference\\\":{\\\"kind\\\":\\\"ReplicaSet\\\",\\\"namespace\\\":\\\"kube-system\\\",\\\"name\\\":\\\"kube-dns-2924299975\\\",\\\"uid\\\":\\\"fa808d95-d7d9-11e6-9ac9-02dfdae1a1e9\\\",\\\"apiVersion\\\":\\\"extensions\\\",\\\"resourceVersion\\\":\\\"89\\\"}}\\n\", \"__meta_kubernetes_pod_annotation_scheduler_alpha_kubernetes_io_affinity\":\"{\\\"nodeAffinity\\\":{\\\"requiredDuringSchedulingIgnoredDuringExecution\\\":{\\\"nodeSelectorTerms\\\":[{\\\"matchExpressions\\\":[{\\\"key\\\":\\\"beta.kubernetes.io/arch\\\",\\\"operator\\\":\\\"In\\\",\\\"values\\\":[\\\"amd64\\\"]}]}]}}}\", \"__meta_kubernetes_pod_name\":\"kube-dns-2924299975-dksg5\", \"__meta_kubernetes_pod_ip\":\"10.32.0.2\", \"__meta_kubernetes_pod_label_k8s_app\":\"kube-dns\", \"__meta_kubernetes_pod_label_pod_template_hash\":\"2924299975\", \"__meta_kubernetes_pod_label_tier\":\"node\", \"__meta_kubernetes_pod_annotation_scheduler_alpha_kubernetes_io_tolerations\":\"[{\\\"key\\\":\\\"dedicated\\\",\\\"value\\\":\\\"master\\\",\\\"effect\\\":\\\"NoSchedule\\\"}]\", \"__meta_kubernetes_namespace\":\"kube-system\", \"__meta_kubernetes_pod_node_name\":\"cluster-manager.dev.example.net\", \"__meta_kubernetes_pod_label_component\":\"kube-dns\", \"__meta_kubernetes_pod_label_kubernetes_io_cluster_service\":\"true\", \"__meta_kubernetes_pod_host_ip\":\"54.194.166.39\", \"__meta_kubernetes_pod_label_name\":\"kube-dns\"}, Source:\"pod/kube-system/kube-dns-2924299975-dksg5\"}"
time="2017-01-25T06:58:04Z" level=debug msg="pod update" kubernetes_sd=pod source="pod.go:66" tg="&config.TargetGroup{Targets:[]model.LabelSet{model.LabelSet{\"__address__\":\"10.43.0.0\", \"__meta_kubernetes_pod_container_name\":\"bot\"}}, Labels:model.LabelSet{\"__meta_kubernetes_pod_host_ip\":\"172.17.101.25\", \"__meta_kubernetes_pod_label_app\":\"bot\", \"__meta_kubernetes_namespace\":\"default\", \"__meta_kubernetes_pod_name\":\"bot-272181271-pnzsz\", \"__meta_kubernetes_pod_ip\":\"10.43.0.0\", \"__meta_kubernetes_pod_node_name\":\"ip-172-17-101-25\", \"__meta_kubernetes_pod_annotation_kubernetes_io_created_by\":\"{\\\"kind\\\":\\\"SerializedReference\\\",\\\"apiVersion\\\":\\\"v1\\\",\\\"reference\\\":{\\\"kind\\\":\\\"ReplicaSet\\\",\\\"namespace\\\":\\\"default\\\",\\\"name\\\":\\\"bot-272181271\\\",\\\"uid\\\":\\\"c297b3c2-e15d-11e6-a28a-02dfdae1a1e9\\\",\\\"apiVersion\\\":\\\"extensions\\\",\\\"resourceVersion\\\":\\\"1465127\\\"}}\\n\", \"__meta_kubernetes_pod_ready\":\"true\", \"__meta_kubernetes_pod_label_pod_template_hash\":\"272181271\", \"__meta_kubernetes_pod_label_version\":\"v0.1\"}, Source:\"pod/default/bot-272181271-pnzsz\"}"
Prometheus fetches updates, but...doesn't convert them to metrics.
So, I've broken my brain to figure out why is it going this way. So, please, help if you can figure out where might be mistake.

Answer 1

If you want to monitor a Kubernetes cluster from an external Prometheus server, I would suggest to set up a Prometheus federation topology:
Inside the K8s, install node-exporter pods and a Prometheus instance with short-term storage.
Expose the Prometheus service out of the K8s cluster, either via an ingress-controller (LB), or a node port. You can protect this endpoint with HTTPS + basic authentication.
Configure the center Prometheus to scrape metrics from above endpoint with proper authentication and tags.
This is the scalable solution. You can add monitor as many K8s clusters you want, until it reaches the capacities of the center Prometheus. Then you can add another center Prometheus instance to monitor others.

Answer 2

Finally I came to the though it's not trivial to setup Kubernetes cluster monitoring outside of cluster. Cause Kubernetes architecture suggested to keep all infrastructure within one local network. So, every workaround is going to be messy.
Also I came to the problem trying to debug why all configured jobs about Kubernetes roles such as nods, pods, services and endpoints doensn't even show up in targets status page. I may think wrong, but I didn't find out how to debug this issue in Prometheus.
My solution to monitor Kubernetes cluster outside was a kube-api-exporter. Pretty simple Python script which gets all metrics about ds, deployments and pods and finally provides the URL to fetch them. So, I'd recommend to come to this solution everyone who's got stuck with this sort of integration.
Also I started to fetch metrics from etcd. That's cool that etcd provides Prometheus-style metrics out of the box.
P.S.: thanks to FuzzyAmi for help.