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Info

Kubernetes-operator

Summary

  • kube-prometheus-stack collects Kubernetes manifests, Grafana dashboards, and Prometheus rules combined with documentation and scripts to provide easy to operate end-to-end Kubernetes cluster monitoring with Prometheus using the Prometheus Operator.
  • Installs the kube-prometheus stack, a collection of Kubernetes manifests, Grafana dashboards, and Prometheus rules combined with documentation and scripts to provide easy to operate end-to-end Kubernetes cluster monitoring with Prometheus using the Prometheus Operator.

Dependencies

By default this chart installs additional, dependent charts:

Guide for kube-prometheus-stack with Helm3.x

02. 사전조건

Info
iconfalse

Prerequisites

  • Kubernetes 1.16+
  • Helm 3+
  1. Kubernetes Cluster 구성
  2. kubectl 설치
  3. Kubernetes Config
  4. helm 설치

03. Namespace 생성

Code Block
sansae@win10pro-worksp:$ kubectl create ns monitor-po

04. Install Chart of kube-prometheus-stack

  • Info

    Operator는 특정 애플리케이션 컨트롤러 인 Kubernetes API를 확장하기 위해 회사에서 개발 한  CoreOS에 의해 생성됩니다 . 

    데이터베이스, 캐싱 및 모니터링 시스템과 같은 복잡한 상태 저장 애플리케이션을 생성, 구성 및 관리하는 데 사용됩니다. 

    Operator는 Kubernetes의 리소스 및 컨트롤러 개념을 기반으로하지만 일부 애플리케이션 별 전문 지식도 포함합니다.

    예를 들어 데이터베이스 운영자를 생성하려면 생성 된 데이터베이스의 다양한 운영 및 유지 관리 방법에 매우 익숙해야합니다. 

    Operator를 만드는 열쇠는 CRD (custom resources)의 디자인입니다.

    Image Added

ServiceMonitor

Summary

  • kube-prometheus-stack collects Kubernetes manifests, Grafana dashboards, and Prometheus rules combined with documentation and scripts to provide easy to operate end-to-end Kubernetes cluster monitoring with Prometheus using the Prometheus Operator.
  • Installs the kube-prometheus stack, a collection of Kubernetes manifests, Grafana dashboards, and Prometheus rules combined with documentation and scripts to provide easy to operate end-to-end Kubernetes cluster monitoring with Prometheus using the Prometheus Operator.

Dependencies

By default this chart installs additional, dependent charts:

Guide for kube-prometheus-stack with Helm3.x

02. 사전조건

Info
iconfalse

Prerequisites

  • Kubernetes 1.16+
  • Helm 3+
  1. Kubernetes Cluster 구성
  2. kubectl 설치
  3. Kubernetes Config
  4. helm 설치

03. Namespace 생성

Code Block
sansae@win10pro-worksp:$ kubectl create ns monitor-po

04. Install Chart of kube-prometheus-stack

Code Block
sansae@win10pro-worksp:$ helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
"prometheus-community" already exists with the same configuration, skipping
sansae@win10pro-worksp:$
sansae@win10pro-worksp:$ helm repo update
Hang tight while we grab the latest from your chart repositories...
...Successfully got an update from the "ingress-nginx" chart repository
...Successfully got an update from the "elastic" chart repository
...Successfully got an update from the "dynatrace" chart repository
...Successfully got an update from the "prometheus-community" chart repository
Update Complete. ⎈Happy Helming!⎈
sansae@win10pro-worksp:$ helm install kube-prometheus-stack prometheus-community/kube-prometheus-stack -n monitor-po
NAME: kube-prometheus-stack
LAST DEPLOYED: Wed Mar 31 10:30:38 2021
NAMESPACE: monitor-po
STATUS: deployed
REVISION: 1
NOTES:
kube-prometheus-stack has been installed. Check its status by running:
  kubectl --namespace monitor-po get pods -l "release=kube-prometheus-stack"

Visit https://github.com/prometheus-operator/kube-prometheus for instructions on how to create & configure Alertmanager and Prometheus instances using the Operator.
sansae@win10pro-worksp:$ kubectl get all -n monitor-po
NAME                                                            READY   STATUS    RESTARTS   AGE
pod/alertmanager-kube-prometheus-stack-alertmanager-0           2/2     Running   0          91s
pod/kube-prometheus-stack-grafana-6b5c8fd86c-lwcv2              2/2     Running   0          93s
pod/kube-prometheus-stack-kube-state-metrics-7877f4cc7c-b2nnc   1/1     Running   0          93s
pod/kube-prometheus-stack-operator-5859b9c949-4n24x             1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-5f4pm        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-5fbc7        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-ggj8c        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-h5cfj        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-hvpsf        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-mbt54        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-s5zd9        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-v7bsj        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-v7sts        1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-vnmx5        1/1     Running   0          93s
pod/prometheus-kube-prometheus-stack-prometheus-0               2/2     Running   1          91s

NAME                                                     TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)
       AGE
service/alertmanager-operated                            ClusterIP   None           <none>        9093/TCP,9094/TCP,9094/UDP   91s
service/kube-prometheus-stack-alertmanager               ClusterIP   10.0.92.245    <none>        9093/TCP
       93s
service/kube-prometheus-stack-grafana
Code Block
sansae@win10pro-worksp:$ helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
"prometheus-community" already exists with the same configuration, skipping
sansae@win10pro-worksp:$
sansae@win10pro-worksp:$ helm repo update
Hang tight while we grab the latest from your chart repositories...
...Successfully got an update from the "ingress-nginx" chart repository
...Successfully got an update from the "elastic" chart repository
...Successfully got an update from the "dynatrace" chart repository
...Successfully got an update from the "prometheus-community" chart repository
Update Complete. ⎈Happy Helming!⎈
sansae@win10pro-worksp:$ helm install kube-prometheus-stack prometheus-community/kube-prometheus-stack -n monitor-po
NAME: kube-prometheus-stack
LAST DEPLOYED: Wed Mar 31 10:30:38 2021
NAMESPACE: monitor-po
STATUS: deployed
REVISION: 1
NOTES:
kube-prometheus-stack has been installed. Check its status by running:
  kubectl --namespace monitor-po get pods -l "release=kube-prometheus-stack"

Visit https://github.com/prometheus-operator/kube-prometheus for instructions on how to create & configure Alertmanager and Prometheus instances using the Operator.
sansae@win10pro-worksp:$ kubectl get all -n monitor-po
NAME                ClusterIP   10.0.240.51    <none>        80/TCP
       93s
service/kube-prometheus-stack-kube-state-metrics         ClusterIP   10.0.47.252    <none>      READY  8080/TCP
 STATUS    RESTARTS   AGE93s
podservice/alertmanager-kube-prometheus-stack-alertmanager-0operator                   ClusterIP   2/210.0.215.243   <none>  Running   0   443/TCP
       91s93s
podservice/kube-prometheus-stack-grafana-6b5c8fd86c-lwcv2prometheus                 ClusterIP   2/210.0.152.193   <none>  Running   0   9090/TCP
       93s
podservice/kube-prometheus-stack-kubeprometheus-state-metrics-7877f4cc7c-b2nncnode-exporter   ClusterIP   1/110.0.216.169   <none>  Running   0   9100/TCP
       93s
podservice/kube-prometheus-stack-operator-5859b9c949-4n24xoperated             1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-5f4pmClusterIP   None      1/1     Running<none>   0     9090/TCP
     93s
pod/kube-prometheus-stack-prometheus-node-exporter-5fbc7  91s

NAME      1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-ggj8c           1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-h5cfj       DESIRED 1/1  CURRENT   RunningREADY   0UP-TO-DATE   AVAILABLE   NODE SELECTOR   93sAGE
poddaemonset.apps/kube-prometheus-stack-prometheus-node-exporter-hvpsf   10        10 1/1     Running  10 0     10     93s
pod/kube-prometheus-stack-prometheus-node-exporter-mbt54      10  1/1     Running   0<none>          93s
pod/kube-prometheus-stack-prometheus-node-exporter-s5zd9
NAME                    1/1     Running   0          93s
pod/kube-prometheus-stack-prometheus-node-exporter-v7bsj        1/1     Running   0 READY   UP-TO-DATE   AVAILABLE   93sAGE
poddeployment.apps/kube-prometheus-stack-prometheus-node-exporter-v7sts-grafana              1/1     Running1            01           93s
poddeployment.apps/kube-prometheus-stack-prometheuskube-nodestate-exporter-vnmx5metrics   1/1     1/1          Running  1 0          93s
poddeployment.apps/prometheus-kube-prometheus-stack-prometheus-0operator               2/2   1/1  Running   1          91s

NAME    1           93s

NAME                                      TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)
       AGE
service/alertmanager-operated     DESIRED   CURRENT   READY   AGE
replicaset.apps/kube-prometheus-stack-grafana-6b5c8fd86c              ClusterIP1   None      1     <none>    1    9093/TCP,9094/TCP,9094/UDP   91s93s
servicereplicaset.apps/kube-prometheus-stack-alertmanager-kube-state-metrics-7877f4cc7c          1     ClusterIP   10.0.92.245    1 <none>        9093/TCP
1       93s
servicereplicaset.apps/kube-prometheus-stack-operator-grafana5859b9c949             1       ClusterIP  1 10.0.240.51    <none>        80/TCP
1       93s
service/kube-prometheus-stack-kube-state-metrics
NAME         ClusterIP   10.0.47.252    <none>        8080/TCP
       93s
service/kube-prometheus-stack-operator                   ClusterIP   10.0.215.243    <none>      READY  443/TCP
   AGE
statefulset.apps/alertmanager-kube-prometheus-stack-alertmanager   1/1     93s91s
servicestatefulset.apps/prometheus-kube-prometheus-stack-prometheus       1/1     91s
sansae@win10pro-worksp:$

05. Volume 설정

05-01. StorageClass 확인

  • Prometheus Stacks에서 사용가능한 StorageClass는 AzureDisk이므로 'default 또는 managed-premium'을 사용해야 합니다.
Code Block
sansae@win10pro-worksp:/workspaces$ kubectl get sc
NAME         ClusterIP   10.0.152.193   <none>        9090/TCP
   PROVISIONER     93s
service/kube-prometheus-stack-prometheus-node-exporter   ClusterIP   10.0.216.169   <none>   RECLAIMPOLICY   VOLUMEBINDINGMODE  9100/TCP
    ALLOWVOLUMEEXPANSION   93s
service/prometheus-operatedAGE
azurefile           kubernetes.io/azure-file   Delete          Immediate      ClusterIP   None     true      <none>        9090/TCP
       91s

NAME65d
azurefile-premium   kubernetes.io/azure-file   Delete          Immediate              true                   65d
default (default)   kubernetes.io/azure-disk   Delete    DESIRED   CURRENT   READYImmediate   UP-TO-DATE   AVAILABLE   NODE SELECTOR   AGE
daemonset.apps/kube-prometheus-stack-prometheus-node-exporter   10 true         10        10  65d
managed    10         kubernetes.io/azure-disk  10 Delete         <none> WaitForFirstConsumer   true      93s

NAME             30d
managed-premium     kubernetes.io/azure-disk   Delete          Immediate              true          READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/kube-prometheus-stack-grafana     65d

05-02. Prometheus Volume

  • Prometheus의 storage에 storageClassName: managed-premium를 추가 합니다.
  • storage 사이즈도 프로젝트스펙에 맞게 적절하게 수정 합니다.
Code Block
sansae@win10pro-worksp:/workspaces$ kubectl get prometheus -n monitor-pga
NAME         1/1     1            1     VERSION   REPLICAS   93sAGE
deployment.apps/kube-prometheus-stack-kube-state-metricsprometheus   1/1v2.24.0     1            1           93s
deployment.apps/kube-prometheus-stack-operator             1/1     1      6d3h


sansae@win10pro-worksp:/workspaces$ kubectl edit prometheus kube-prometheus-stack-prometheus -n monitor-po
=============================================================
156   storage:
157     volumeClaimTemplate:
158      1 spec:
159          93s

NAMEaccessModes:
160         - ReadWriteOnce
161         resources:
162           requests:
163             storage: 50Gi
164                      DESIRED   CURRENT   READY   AGE
replicaset.appsstorageClassName: managed-premium
=============================================================

prometheus.monitoring.coreos.com/kube-prometheus-stack-grafana-6b5c8fd86c     prometheus edited


sansae@win10pro-worksp:/workspaces$ kubectl get pvc -n monitor-po
NAME         1         1         1       93s
replicaset.apps/kube-prometheus-stack-kube-state-metrics-7877f4cc7c   1         1         1       93s
replicaset.apps/kube-prometheus-stack-operator-5859b9c949             1         1         1      STATUS 93s

NAME  VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS      AGE
prometheus-kube-prometheus-stack-prometheus-db-prometheus-kube-prometheus-stack-prometheus-0           READYBound   AGE
statefulset.apps/alertmanager-kube-prometheus-stack-alertmanager   1/1 pvc-64f88c7f-6fad-4d66-b6eb-xxxxxxxxx   50Gi       91s
statefulset.apps/prometheus-kube-prometheus-stack-prometheusRWO       1/1     91s
sansae@win10pro-worksp:$managed-premium   6d2h

05-03. Alertmanager Volume

...

05-01. StorageClass 확인

...

  • Alertmanager의 storage에 storageClassName: managed-premium를 추가 합니다.
  • storage 사이즈도 프로젝트스펙에 맞게 적절하게 수정 합니다.
Code Block
sansae@win10pro-worksp:/workspaces$ kubectl get sc alertmanager -n monitor-po
NAME                PROVISIONER                RECLAIMPOLICY  VERSION VOLUMEBINDINGMODE  REPLICAS    ALLOWVOLUMEEXPANSION   AGE
azurefilekube-prometheus-stack-alertmanager           kubernetes.io/azure-filev0.21.0   Delete1          Immediate              true                   65d
azurefile-premium   kubernetes.io/azure-file   Delete    6d3h


sansae@win10pro-worksp:/workspaces$ kubectl edit alertmanager kube-prometheus-stack-alertmanager -n monitor-po
=============================================================
  storage:
    volumeClaimTemplate:
      spec:
      Immediate  accessModes:
        - ReadWriteOnce
   true     resources:
              65d
default (default)requests:
    kubernetes.io/azure-disk   Delete          Immediate              true      storage: 2Gi
             65d
managed             kubernetes.io/azure-disk   DeletestorageClassName: managed-premium
=============================================================
alertmanager.monitoring.coreos.com/kube-prometheus-stack-alertmanager edited


sansae@win10pro-worksp:/workspaces$ kubectl get pvc -n monitor-po
NAME             WaitForFirstConsumer   true                   30d
managed-premium     kubernetes.io/azure-disk   Delete          Immediate              true                   65d

05-02. Prometheus Volume

  • Prometheus의 storage에 storageClassName: managed-premium를 추가 합니다.
  • storage 사이즈도 프로젝트스펙에 맞게 적절하게 수정 합니다.
Code Block
sansae@win10pro-worksp:/workspaces$ kubectl edit prometheus kube-prometheus-stack-prometheus -n monitor-po

=============================================================
156   storage:
157     volumeClaimTemplate:
158             STATUS   VOLUME                               spec:
159      CAPACITY   accessModes:
160ACCESS MODES   STORAGECLASS     - ReadWriteOnce
161AGE
alertmanager-kube-prometheus-stack-alertmanager-db-alertmanager-kube-prometheus-stack-alertmanager-0   Bound    pvc-5e7b02eb-7109-417d-9c14-xxxxxxxx  resources:
162 2Gi        RWO  requests:
163          managed-premium   storage: 50Gi
164         storageClassName: managed-premium6d2h

05-04. Grafana Volume

  • Grafana는 Prometheus-operator로 구성된 리소스가 아닙니다.
  • 따라서, PVC를 수동으로 생성하고, Deployment에 PVC를 사용하도록 수정해 줍니다.
Code Block
sansae@win10pro-worksp:/workspaces$ vim grafana-pvc.yaml
=============================================================

prometheus.monitoring.coreos.com/kube-prometheus-stack-prometheus edited

05-03. Alertmanager Volume

  • Alertmanager의 storage에 storageClassName: managed-premium를 추가 합니다.
  • storage 사이즈도 프로젝트스펙에 맞게 적절하게 수정 합니다.
Code Block
sansae@win10pro-worksp:/workspaces$ kubectl edit alertmanager kube-prometheus-stack-alertmanager -n monitor-po
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: grafana-pv-claim
  labels:
    app: grafana
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
  storageClassName: managed-premium
==================================================================
 85   storage:
 86=====
sansae@win10pro-worksp:/workspaces$ kubectl create -f grafana-pvc.yaml
create pvc!!!



sansae@win10pro-worksp:/workspaces$ kubectl get deploy -n monitor-pga
NAME                   volumeClaimTemplate:
 87       spec:
 88         storageClassName: managed-premium
 89READY   UP-TO-DATE   AVAILABLE   accessModes: ["ReadWriteOnce"]
 90AGE
kube-prometheus-stack-grafana           resources:
 91  1/1     1    requests:
 92       1      storage: 2Gi
=============================================================
alertmanager.monitoring.coreos.com/     6d3h


sansae@win10pro-worksp:/workspaces$ kubectl edit deploy kube-prometheus-stack-alertmanagergrafana edited

05-04. Grafana Volume

  • Grafana는 Prometheus-operator로 구성된 리소스가 아닙니다.
  • 따라서, PVC를 수동으로 생성하고, Deployment에 PVC를 사용하도록 수정해 줍니다.
Code Block
sansae@win10pro-worksp:/workspaces$ cat grafana-pvc.yaml
-n monitor-po
================================================================
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: grafana-pv-claim
  labels:
    app: grafana
spec:
  accessModes:
=====
       volumeMounts:
       - mountPath: /var/lib/grafana
         name: grafana-persistent-storage
-------------------------------------------------------
       volumes:
       - ReadWriteOnce
  resources:name: grafana-persistent-storage
    requests:
      storagepersistentVolumeClaim: 1Gi
  storageClassName: managed-premium
=============================================================
sansae@win10pro-worksp:/workspaces$ kubectl create -f grafana-pvc.yaml
create pvc!!!

sansae@win10pro-worksp:/workspaces$ kubectl edit deploy kube-prometheus-stack-grafana -n monitor-po
           claimName: grafana-pv-claim
=============================================================
400========
deployment.apps/kube-prometheus-stack-grafana edited


sansae@win10pro-worksp:/workspaces$ kubectl get pvc -n monitor-po
NAME                  STATUS   VOLUME                               - mountPath: /var/lib/grafana
401 CAPACITY   ACCESS MODES   STORAGECLASS    name: grafana-persistent-storage
-------------------------------------------------------
453  AGE
grafana-pv-claim      Bound  - name: grafana-persistent-storage
454  pvc-a13463fa-ebda-4632-a9c0-xxxxxxxx   1Gi     persistentVolumeClaim:
455   RWO        claimName: grafana-pv-claim
=============================================================
deployment.apps/kube-prometheus-stack-grafana edited    managed-premium   6d2h

06. Service Connection

06-01. Prometheus Operated

...

Code Block
sansae@win10pro-worksp:$ kubectl port-forward service/kube-prometheus-stack-alertmanager 9093:9093 -n monitor-po
Forwarding from 127.0.0.1:9093 -> 9093
Forwarding from [::1]:9093 -> 9093

Image Removed

참고: 삭제할 경우 namespace이외에 삭제 해야할 리소스

 -> 9093
Forwarding from [::1]:9093 -> 9093

Image Added


참고: 삭제할 경우 namespace이외에 삭제 해야할 리소스

Code Block
for n in $(kubectl get namespaces -o jsonpath={..metadata.name}); do
  kubectl delete --all --namespace=$n prometheus,servicemonitor,podmonitor,alertmanager
done
Code Block
kubectl delete crd alertmanagerconfigs.monitoring.coreos.com
kubectl delete crd alertmanagers.monitoring.coreos.com
kubectl delete crd podmonitors.monitoring.coreos.com
kubectl delete crd probes.monitoring.coreos.com
kubectl delete crd prometheuses.monitoring.coreos.com
kubectl delete crd prometheusrules.monitoring.coreos.com
kubectl delete crd servicemonitors.monitoring.coreos.com
kubectl delete crd thanosrulers.monitoring.coreos.com

kubectl delete clusterrole kube-prometheus-stack-grafana-clusterrole
kubectl delete clusterrole kube-prometheus-stack-kube-state-metrics
kubectl delete clusterrole kube-prometheus-stack-operator
kubectl delete clusterrole kube-prometheus-stack-operator-psp
kubectl delete clusterrole kube-prometheus-stack-prometheus
kubectl delete clusterrole kube-prometheus-stack-prometheus-psp
kubectl delete clusterrole psp-kube-prometheus-stack-kube-state-metrics
kubectl delete clusterrole psp-kube-prometheus-stack-prometheus-node-exporter

kubectl delete clusterrolebinding kube-prometheus-stack-grafana-clusterrolebinding
kubectl delete clusterrolebinding kube-prometheus-stack-kube-state-metrics
kubectl delete clusterrolebinding kube-prometheus-stack-operator
kubectl delete clusterrolebinding kube-prometheus-stack-operator-psp
kubectl delete clusterrolebinding kube-prometheus-stack-prometheus
kubectl delete clusterrolebinding kube-prometheus-stack-prometheus-psp
kubectl delete clusterrolebinding psp-kube-prometheus-stack-kube-state-metrics
kubectl delete clusterrolebinding psp-kube-prometheus-stack-prometheus-node-exporter

kubectl delete svc kube-prometheus-stack-coredns -n kube-system
kubectl delete svc kube-prometheus-stack-kube-controller-manager -n kube-system
kubectl delete svc kube-prometheus-stack-kube-etcd -n kube-system
kubectl delete svc kube-prometheus-stack-kube-proxy -n kube-system
kubectl delete svc kube-prometheus-stack-kube-scheduler -n kube-system
kubectl delete svc kube-prometheus-stack-kubelet -n kube-system
kubectl delete svc prometheus-kube-prometheus-kubelet -n kube-system

kubectl delete MutatingWebhookConfiguration kube-prometheus-stack-admission
kubectl delete ValidatingWebhookConfiguration kubekube-prometheus-stack-admission


참조:

Info

https://containerjournal.com/topics/container-management/cluster-monitoring-with-prometheus-

stack-admission

참조:

operator/

https://kangwoo.kr/2020/06/20/kubernetes-monitoring-3-kube-prometheus-%ec%84%a4%ec%b9%98-%ed%9b%84-%ed%95%b4%ec%95%bc-%ed%95%a0%ec%9d%bc/

https://waspro.tistory.com/588

https://strange-developer.tistory.com/53

https://docs.syseleven.de/metakube/de/metakube-accelerator/building-blocks/observability-monitoring/kube-prometheus-stack

https://kangwoo.kr/2020/06/13/kubernetes-monitoring-1-kube-prometheus-%EC%84%A4%EC%B9%98%ED%95%98%EA%B8%B0/