Kubernetes—部署监控系统

使用Prometheus全方位监控K8S

一、Prometheus架构

1.含义
https://prometheus.io
https://github.com/prometheus
Prometheus（普罗米修斯）是一个最初在SoundCloud上构建的监控系统。自2012年成为社区开源项目，拥
有非常活跃的开发人员和用户社区。为强调开源及独立维护，Prometheus于2016年加入云原生云计算基金会 （CNCF），成为继Kubernetes之后的第二个托管项目。
2.结构

• Prometheus Server：收集指标和存储时间序列数据，并提供查询接口
• ClientLibrary：客户端库
• Push Gateway：短期存储指标数据。主要用于临时性的任务
• Exporters：采集已有的第三方服务监控指标并暴露metrics
• Alertmanager：告警
• Web UI：简单的Web控制台

3.数据模型

Prometheus将所有数据存储为时间序列；具有相同度量名称以及标签属于同一个指标。
每个时间序列都由度量标准名称和一组键值对（也成为标签）唯一标识。
时间序列格式：
{=, …}
示例：api_http_requests_total{method=“POST”, handler="/messages"}

4.作业和实例

实例：可以抓取的目标称为实例（Instances） - job_name: ‘prometheus’
作业：具有相同目标的实例集合称为作业（Job）
scrape_configs:

• job_name: ‘prometheus’
  static_configs:
  • targets: [‘localhost:9090’]
• job_name: ‘node’
  static_configs:
• targets: [‘192.168.1.10:9090’]

二、K8S监控指标及实现思路

1.监控指标
Kubernetes本身监控
• Node资源利用率
• Node数量
• Pods数量（Node）
• 资源对象状态
Pod监控
• Pod数量（项目）
• 容器资源利用率
• 应用程序
2.架构


在原先的版本中cAdvisor是开放端口的，现在是内置可以采集数据也是通过kubelet采集
Heapster也是用cAdvisor
服务发现：
https://prometheus.io/docs/prometheus/latest/configuration/configuration/#kubernetes_sd_config

三、 在K8S平台部署Prometheus

https://github.com/kubernetes/kubernetes/tree/master/cluster/addons/prometheus
https://grafana.com/grafana/download

1.监控K8S集群中Pod、Node、资源对象

Pod
kubelet的节点使用cAdvisor提供的metrics接口获取该节点所有Pod和容器相关的性能指标数据。
暴露接口地址：
https://NodeIP:10255/metrics/cadvisor
https://NodeIP:10250/metrics/cadvisor
 Node
使用node_exporter收集器采集节点资源利用率。
https://github.com/prometheus/node_exporter
使用文档：https://prometheus.io/docs/guides/node-exporter/
 资源对象
kube-state-metrics采集了k8s中各种资源对象的状态信息，
https://github.com/kubernetes/kube-state-metrics

2.部署Prometheus和grafana
[root@k8s-master prometheus-k8s]# kubectl apply -f prometheus-configmap.yaml
[root@k8s-master prometheus-k8s]# kubectl apply -f prometheus-rules.yaml
[root@k8s-master prometheus-k8s]# kubectl apply -f prometheus-rbac.yaml
[root@k8s-master prometheus-k8s]# kubectl apply -f prometheus-statefulset.yaml
这里用的是nfs的pv自动供给，如果没有可以选择手动pv，pvc
[root@k8s-master prometheus-k8s]# kubectl apply -f prometheus-service.yaml
这里的Prometheus和grafana都是使用的service的nodeport
3.部署node节点的node_export
[root@k8s-master prometheus-k8s]# scp node_exporter.sh 192.168.74.246:/root
[root@k8s-master prometheus-k8s]# scp node_exporter.sh 192.168.74.247:/root
执行脚本

#!/bin/bash
#wget https://github.com/prometheus/node_exporter/releases/download/v0.17.0/node_exporter-0.17.0.linux-amd64.tar.gz
tar zxf node_exporter-0.17.0.linux-amd64.tar.gz
mv node_exporter-0.17.0.linux-amd64 /usr/local/node_exporter
cat <<EOF >/usr/lib/systemd/system/node_exporter.service
[Unit]
Description=https://prometheus.io
[Service]
Restart=on-failure
ExecStart=/usr/local/node_exporter/node_exporter --collector.systemd --collector.systemd.unit-whitelist=(docker|kubelet|kube-proxy|flanneld).service
[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl enable node_exporter
systemctl restart node_exporter

4.部署检测node节点需要的pod
kubectl apply -f kube-state-metrics-service.yaml
kubectl apply -f kube-state-metrics-rbac.yaml
kubectl apply -f kube-state-metrics-deployment.yaml

四、 监控K8S集群中Pod、Node、资源对象

推荐模板：
• 集群资源监控：3119
• 资源状态监控 ：6417
• Node监控 ：9276
因为kube-state-metrics-service.yaml 有如下，会自动连接api就可以自动监控
annotations:
prometheus.io/scrape: ‘true’
所以我们部署应用只要带这个注解 就会被检测到，被监控

五、告警规则与告警通知

1. 部署Alertmanager

2.配置Prometheus与Alertmanager通信
需要修改alertmanager-configmap.yaml中的发件人和收件人
[root@k8s-master prometheus-k8s]# kubectl apply -f alertmanager-configmap.yaml
[root@k8s-master prometheus-k8s]# kubectl apply -f alertmanager-pvc.yaml

六、一些上文yaml文件事例

1.prometheus-rbac.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
  name: prometheus
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: prometheus
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile 
rules:
  - apiGroups:
      - ""
    resources:
      - nodes
      - nodes/metrics
      - services
      - endpoints
      - pods
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - configmaps
    verbs:
      - get
  - nonResourceURLs:
      - "/metrics"
    verbs:
      - get
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: prometheus
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: prometheus
subjects:
- kind: ServiceAccount
  name: prometheus
  namespace: kube-system

2.prometheus-rules.yaml

apiVersion: v1
kind: ConfigMap
metadata:
  name: prometheus-rules
  namespace: kube-system
data:
  general.rules: |
    groups:
    - name: general.rules
      rules:
      - alert: InstanceDown
        expr: up == 0
        for: 1m
        labels:
          severity: error 
        annotations:
          summary: "Instance {{ $labels.instance }} 停止工作"
          description: "{{ $labels.instance }} job {{ $labels.job }} 已经停止5分钟以上."
  node.rules: |
    groups:
    - name: node.rules
      rules:
      - alert: NodeFilesystemUsage
        expr: 100 - (node_filesystem_free_bytes{fstype=~"ext4|xfs"} / node_filesystem_size_bytes{fstype=~"ext4|xfs"} * 100) > 80 
        for: 1m
        labels:
          severity: warning 
        annotations:
          summary: "Instance {{ $labels.instance }} : {{ $labels.mountpoint }} 分区使用率过高"
          description: "{{ $labels.instance }}: {{ $labels.mountpoint }} 分区使用大于80% (当前值: {{ $value }})"

      - alert: NodeMemoryUsage
        expr: 100 - (node_memory_MemFree_bytes+node_memory_Cached_bytes+node_memory_Buffers_bytes) / node_memory_MemTotal_bytes * 100 > 80
        for: 1m
        labels:
          severity: warning
        annotations:
          summary: "Instance {{ $labels.instance }} 内存使用率过高"
          description: "{{ $labels.instance }}内存使用大于80% (当前值: {{ $value }})"

      - alert: NodeCPUUsage    
        expr: 100 - (avg(irate(node_cpu_seconds_total{mode="idle"}[5m])) by (instance) * 100) > 60 
        for: 1m
        labels:
          severity: warning
        annotations:
          summary: "Instance {{ $labels.instance }} CPU使用率过高"       
          description: "{{ $labels.instance }}CPU使用大于60% (当前值: {{ $value }})"

3.prometheus-service.yaml

kind: Service
apiVersion: v1
metadata: 
  name: prometheus
  namespace: kube-system
  labels: 
    kubernetes.io/name: "Prometheus"
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
spec: 
  type: NodePort
  ports: 
    - name: http 
      port: 9090
      protocol: TCP
      targetPort: 9090
  selector: 
    k8s-app: prometheus

4.prometheus-statefulset.yaml

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: prometheus 
  namespace: kube-system
  labels:
    k8s-app: prometheus
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    version: v2.2.1
spec:
  serviceName: "prometheus"
  replicas: 1
  podManagementPolicy: "Parallel"
  updateStrategy:
   type: "RollingUpdate"
  selector:
    matchLabels:
      k8s-app: prometheus
  template:
    metadata:
      labels:
        k8s-app: prometheus
      annotations:
        scheduler.alpha.kubernetes.io/critical-pod: ''
    spec:
      priorityClassName: system-cluster-critical
      serviceAccountName: prometheus
      initContainers:
      - name: "init-chown-data"
        image: "busybox:latest"
        imagePullPolicy: "IfNotPresent"
        command: ["chown", "-R", "65534:65534", "/data"]
        volumeMounts:
        - name: prometheus-data
          mountPath: /data
          subPath: ""
      containers:
        - name: prometheus-server-configmap-reload
          image: "jimmidyson/configmap-reload:v0.1"
          imagePullPolicy: "IfNotPresent"
          args:
            - --volume-dir=/etc/config
            - --webhook-url=http://localhost:9090/-/reload
          volumeMounts:
            - name: config-volume
              mountPath: /etc/config
              readOnly: true
          resources:
            limits:
              cpu: 10m
              memory: 10Mi
            requests:
              cpu: 10m
              memory: 10Mi

        - name: prometheus-server
          image: "prom/prometheus:v2.2.1"
          imagePullPolicy: "IfNotPresent"
          args:
            - --config.file=/etc/config/prometheus.yml
            - --storage.tsdb.path=/data
            - --web.console.libraries=/etc/prometheus/console_libraries
            - --web.console.templates=/etc/prometheus/consoles
            - --web.enable-lifecycle
          ports:
            - containerPort: 9090
          readinessProbe:
            httpGet:
              path: /-/ready
              port: 9090
            initialDelaySeconds: 30
            timeoutSeconds: 30
          livenessProbe:
            httpGet:
              path: /-/healthy
              port: 9090
            initialDelaySeconds: 30
            timeoutSeconds: 30
          # based on 10 running nodes with 30 pods each
          resources:
            limits:
              cpu: 200m
              memory: 1000Mi
            requests:
              cpu: 200m
              memory: 1000Mi
            
          volumeMounts:
            - name: config-volume
              mountPath: /etc/config
            - name: prometheus-data
              mountPath: /data
              subPath: ""
            - name: prometheus-rules
              mountPath: /etc/config/rules

      terminationGracePeriodSeconds: 300
      volumes:
        - name: config-volume
          configMap:
            name: prometheus-config
        - name: prometheus-rules
          configMap:
            name: prometheus-rules

  volumeClaimTemplates:
  - metadata:
      name: prometheus-data
    spec:
      storageClassName: managed-nfs-storage 
      accessModes:
        - ReadWriteOnce
      resources:
        requests:
          storage: "16Gi"

5.kube-state-metrics-service.yaml

apiVersion: v1
kind: Service
metadata:
  name: kube-state-metrics
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    kubernetes.io/name: "kube-state-metrics"
  annotations:
    prometheus.io/scrape: 'true'
spec:
  ports:
  - name: http-metrics
    port: 8080
    targetPort: http-metrics
    protocol: TCP
  - name: telemetry
    port: 8081
    targetPort: telemetry
    protocol: TCP
  selector:
    k8s-app: kube-state-metrics

6.kube-state-metrics-rbac.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
  name: kube-state-metrics
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: kube-state-metrics
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
rules:
- apiGroups: [""]
  resources:
  - configmaps
  - secrets
  - nodes
  - pods
  - services
  - resourcequotas
  - replicationcontrollers
  - limitranges
  - persistentvolumeclaims
  - persistentvolumes
  - namespaces
  - endpoints
  verbs: ["list", "watch"]
- apiGroups: ["extensions"]
  resources:
  - daemonsets
  - deployments
  - replicasets
  verbs: ["list", "watch"]
- apiGroups: ["apps"]
  resources:
  - statefulsets
  verbs: ["list", "watch"]
- apiGroups: ["batch"]
  resources:
  - cronjobs
  - jobs
  verbs: ["list", "watch"]
- apiGroups: ["autoscaling"]
  resources:
  - horizontalpodautoscalers
  verbs: ["list", "watch"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  name: kube-state-metrics-resizer
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
rules:
- apiGroups: [""]
  resources:
  - pods
  verbs: ["get"]
- apiGroups: ["extensions"]
  resources:
  - deployments
  resourceNames: ["kube-state-metrics"]
  verbs: ["get", "update"]
---
apiVersion: rbac.authorization.k8s.io/v1 
kind: ClusterRoleBinding
metadata:
  name: kube-state-metrics
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: kube-state-metrics
subjects:
- kind: ServiceAccount
  name: kube-state-metrics
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: kube-state-metrics
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: kube-state-metrics-resizer
subjects:
- kind: ServiceAccount
  name: kube-state-metrics
  namespace: kube-system

7.prometheus-configmap.yaml

# Prometheus configuration format https://prometheus.io/docs/prometheus/latest/configuration/configuration/
apiVersion: v1
kind: ConfigMap
metadata:
  name: prometheus-config
  namespace: kube-system 
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: EnsureExists
data:
  prometheus.yml: |
    rule_files:
    - /etc/config/rules/*.rules

    scrape_configs:
    - job_name: prometheus
      static_configs:
      - targets:
        - localhost:9090

    - job_name: kubernetes-nodes
      scrape_interval: 30s
      static_configs:
      - targets:
        - redis.default.svc.cluster.local:9121
        - redis-test.default.svc.cluster.local:9121
    - job_name: kubernetes-apiservers
      kubernetes_sd_configs:
      - role: endpoints
      relabel_configs:
      - action: keep
        regex: default;kubernetes;https
        source_labels:
        - __meta_kubernetes_namespace
        - __meta_kubernetes_service_name
        - __meta_kubernetes_endpoint_port_name
      scheme: https
      tls_config:
        ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
        insecure_skip_verify: true
      bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
 
    - job_name: kubernetes-nodes-kubelet
      kubernetes_sd_configs:
      - role: node
      relabel_configs:
      - action: labelmap
        regex: __meta_kubernetes_node_label_(.+)
      scheme: https
      tls_config:
        ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
        insecure_skip_verify: true
      bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token

    - job_name: kubernetes-nodes-cadvisor
      kubernetes_sd_configs:
      - role: node
      relabel_configs:
      - action: labelmap
        regex: __meta_kubernetes_node_label_(.+)
      - target_label: __metrics_path__
        replacement: /metrics/cadvisor
      scheme: https
      tls_config:
        ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
        insecure_skip_verify: true
      bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token

    - job_name: kubernetes-service-endpoints
      kubernetes_sd_configs:
      - role: endpoints
      relabel_configs:
      - action: keep
        regex: true
        source_labels:
        - __meta_kubernetes_service_annotation_prometheus_io_scrape
      - action: replace
        regex: (https?)
        source_labels:
        - __meta_kubernetes_service_annotation_prometheus_io_scheme
        target_label: __scheme__
      - action: replace
        regex: (.+)
        source_labels:
        - __meta_kubernetes_service_annotation_prometheus_io_path
        target_label: __metrics_path__
      - action: replace
        regex: ([^:]+)(?::\d+)?;(\d+)
        replacement: $1:$2
        source_labels:
        - __address__
        - __meta_kubernetes_service_annotation_prometheus_io_port
        target_label: __address__
      - action: labelmap
        regex: __meta_kubernetes_service_label_(.+)
      - action: replace
        source_labels:
        - __meta_kubernetes_namespace
        target_label: kubernetes_namespace
      - action: replace
        source_labels:
        - __meta_kubernetes_service_name
        target_label: kubernetes_name

    - job_name: kubernetes-services
      kubernetes_sd_configs:
      - role: service
      metrics_path: /probe
      params:
        module:
        - http_2xx
      relabel_configs:
      - action: keep
        regex: true
        source_labels:
        - __meta_kubernetes_service_annotation_prometheus_io_probe
      - source_labels:
        - __address__
        target_label: __param_target
      - replacement: blackbox
        target_label: __address__
      - source_labels:
        - __param_target
        target_label: instance
      - action: labelmap
        regex: __meta_kubernetes_service_label_(.+)
      - source_labels:
        - __meta_kubernetes_namespace
        target_label: kubernetes_namespace
      - source_labels:
        - __meta_kubernetes_service_name
        target_label: kubernetes_name

    - job_name: kubernetes-pods
      kubernetes_sd_configs:
      - role: pod
      relabel_configs:
      - action: keep
        regex: true
        source_labels:
        - __meta_kubernetes_pod_annotation_prometheus_io_scrape
      - action: replace
        regex: (.+)
        source_labels:
        - __meta_kubernetes_pod_annotation_prometheus_io_path
        target_label: __metrics_path__
      - action: replace
        regex: ([^:]+)(?::\d+)?;(\d+)
        replacement: $1:$2
        source_labels:
        - __address__
        - __meta_kubernetes_pod_annotation_prometheus_io_port
        target_label: __address__
      - action: labelmap
        regex: __meta_kubernetes_pod_label_(.+)
      - action: replace
        source_labels:
        - __meta_kubernetes_namespace
        target_label: kubernetes_namespace
      - action: replace
        source_labels:
        - __meta_kubernetes_pod_name
        target_label: kubernetes_pod_name
    alerting:
      alertmanagers:
      - static_configs:
          - targets: ["alertmanager:80"]

8.kube-state-metrics-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: kube-state-metrics
  namespace: kube-system
  labels:
    k8s-app: kube-state-metrics
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    version: v1.3.0
spec:
  selector:
    matchLabels:
      k8s-app: kube-state-metrics
      version: v1.3.0
  replicas: 1
  template:
    metadata:
      labels:
        k8s-app: kube-state-metrics
        version: v1.3.0
      annotations:
        scheduler.alpha.kubernetes.io/critical-pod: ''
    spec:
      priorityClassName: system-cluster-critical
      serviceAccountName: kube-state-metrics
      containers:
      - name: kube-state-metrics
        image: lizhenliang/kube-state-metrics:v1.3.0
        ports:
        - name: http-metrics
          containerPort: 8080
        - name: telemetry
          containerPort: 8081
        readinessProbe:
          httpGet:
            path: /healthz
            port: 8080
          initialDelaySeconds: 5
          timeoutSeconds: 5
      - name: addon-resizer
        image: lizhenliang/addon-resizer:1.8.3
        resources:
          limits:
            cpu: 100m
            memory: 30Mi
          requests:
            cpu: 100m
            memory: 30Mi
        env:
          - name: MY_POD_NAME
            valueFrom:
              fieldRef:
                fieldPath: metadata.name
          - name: MY_POD_NAMESPACE
            valueFrom:
              fieldRef:
                fieldPath: metadata.namespace
        volumeMounts:
          - name: config-volume
            mountPath: /etc/config
        command:
          - /pod_nanny
          - --config-dir=/etc/config
          - --container=kube-state-metrics
          - --cpu=100m
          - --extra-cpu=1m
          - --memory=100Mi
          - --extra-memory=2Mi
          - --threshold=5
          - --deployment=kube-state-metrics
      volumes:
        - name: config-volume
          configMap:
            name: kube-state-metrics-config
---
# Config map for resource configuration.
apiVersion: v1
kind: ConfigMap
metadata:
  name: kube-state-metrics-config
  namespace: kube-system
  labels:
    k8s-app: kube-state-metrics
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
data:
  NannyConfiguration: |-
    apiVersion: nannyconfig/v1alpha1
    kind: NannyConfiguration

9.grafana.yaml

apiVersion: apps/v1 
kind: StatefulSet 
metadata:
  name: grafana
  namespace: kube-system
spec:
  serviceName: "grafana"
  replicas: 1
  selector:
    matchLabels:
      app: grafana
  template:
    metadata:
      labels:
        app: grafana
    spec:
      containers:
      - name: grafana
        image: grafana/grafana
        ports:
          - containerPort: 3000
            protocol: TCP
        resources:
          limits:
            cpu: 100m            
            memory: 256Mi          
          requests:
            cpu: 100m            
            memory: 256Mi
        volumeMounts:
          - name: grafana-data
            mountPath: /var/lib/grafana
            subPath: grafana
      securityContext:
        fsGroup: 472
        runAsUser: 472
  volumeClaimTemplates:
  - metadata:
      name: grafana-data
    spec:
      storageClassName: managed-nfs-storage 
      accessModes:
        - ReadWriteOnce
      resources:
        requests:
          storage: "1Gi"

---

apiVersion: v1
kind: Service
metadata:
  name: grafana
  namespace: kube-system
spec:
  type: NodePort
  ports:
  - port : 80
    targetPort: 3000
    nodePort: 30007
  selector:
    app: grafana

10.alertmanager-configmap.yaml

apiVersion: v1
kind: ConfigMap
metadata:
  name: alertmanager-config
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: EnsureExists
data:
  alertmanager.yml: |
    global: 
      resolve_timeout: 5m
      smtp_smarthost: 'smtp.163.com:25'
      smtp_from: '[email protected]'
      smtp_auth_username: '[email protected]'
      smtp_auth_password: 'liang123'

    receivers:
    - name: default-receiver
      email_configs:
      - to: "[email protected]"

    route:
      group_interval: 1m
      group_wait: 10s
      receiver: default-receiver
      repeat_interval: 1m

11.alertmanager-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: alertmanager
  namespace: kube-system
  labels:
    k8s-app: alertmanager
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    version: v0.14.0
spec:
  replicas: 1
  selector:
    matchLabels:
      k8s-app: alertmanager
      version: v0.14.0
  template:
    metadata:
      labels:
        k8s-app: alertmanager
        version: v0.14.0
      annotations:
        scheduler.alpha.kubernetes.io/critical-pod: ''
    spec:
      priorityClassName: system-cluster-critical
      containers:
        - name: prometheus-alertmanager
          image: "prom/alertmanager:v0.14.0"
          imagePullPolicy: "IfNotPresent"
          args:
            - --config.file=/etc/config/alertmanager.yml
            - --storage.path=/data
            - --web.external-url=/
          ports:
            - containerPort: 9093
          readinessProbe:
            httpGet:
              path: /#/status
              port: 9093
            initialDelaySeconds: 30
            timeoutSeconds: 30
          volumeMounts:
            - name: config-volume
              mountPath: /etc/config
            - name: storage-volume
              mountPath: "/data"
              subPath: ""
          resources:
            limits:
              cpu: 10m
              memory: 50Mi
            requests:
              cpu: 10m
              memory: 50Mi
        - name: prometheus-alertmanager-configmap-reload
          image: "jimmidyson/configmap-reload:v0.1"
          imagePullPolicy: "IfNotPresent"
          args:
            - --volume-dir=/etc/config
            - --webhook-url=http://localhost:9093/-/reload
          volumeMounts:
            - name: config-volume
              mountPath: /etc/config
              readOnly: true
          resources:
            limits:
              cpu: 10m
              memory: 10Mi
            requests:
              cpu: 10m
              memory: 10Mi
      volumes:
        - name: config-volume
          configMap:
            name: alertmanager-config
        - name: storage-volume
          persistentVolumeClaim:
            claimName: alertmanager

12.alertmanager-pvc.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: alertmanager
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: EnsureExists
spec:
  storageClassName: managed-nfs-storage 
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: "2Gi"

13.alertmanager-service.yaml

apiVersion: v1
kind: Service
metadata:
  name: alertmanager
  namespace: kube-system
  labels:
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    kubernetes.io/name: "Alertmanager"
spec:
  ports:
    - name: http
      port: 80
      protocol: TCP
      targetPort: 9093
  selector:
    k8s-app: alertmanager 
  type: "ClusterIP"