K8s: Prometheus 监控主机 和 K8s 集群

Prometheus 监控主机 和 K8s 集群

1 ）搭建 Prometheus

• 创建对应 ServiceAccount
  • 达成角色访问的目的，避免所有人都能看到
• 创建配置相关的 configmap
  • 定义了一堆的任务，收集各个层面的监控数据
• 创建告警规则相关的configmap
  • 比如内存大于 75% 就加入一些标签
  • 并且可以出发一些事件
• 创建Prometheus的缺省用户及密码
  • 缺省用户/密码为admin/admin： echo “YWRtaW4=” | base64 -D
• 部署Prometheus Server的Deployment
  • 对外提供 容器 9090 端口，并挂载2个configMap
  • 原始docker image是prom/prometheus:v1.7.0
• 部署Prometheus Server的Service
  • 部署后即可在外部访问
  • :30091/graph 这个路径
  • 可以选择下拉菜单，看到不同维度的数据
  • 可以看到 Prometheus 的报表没有那么强大

2 ） 一键部署

apiVersion: v1
kind: Namespace
metadata:
  name: monitoring
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: prometheus
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: prometheus
subjects:
- kind: ServiceAccount
  name: prometheus-k8s
  namespace: monitoring
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: prometheus
rules:
- apiGroups: [""]
  resources:
  - nodes
  - nodes/proxy
  - services
  - endpoints
  - pods
  verbs: ["get", "list", "watch"]
- apiGroups: [""]
  resources:
  - configmaps
  verbs: ["get"]
- nonResourceURLs: ["/metrics"]
  verbs: ["get"]
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: prometheus-k8s
  namespace: monitoring
---
apiVersion: v1
kind: ConfigMap
metadata:
  creationTimestamp: null
  name: prometheus-core
  namespace: monitoring
data:
  prometheus.yaml: |
    global:
      scrape_interval: 10s
      scrape_timeout: 10s
      evaluation_interval: 10s
    rule_files:
      - "/etc/prometheus-rules/*.rules"
    scrape_configs:

      # https://github.com/prometheus/prometheus/blob/master/documentation/examples/prometheus-kubernetes.yml#L37
      - job_name: 'kubernetes-nodes'
        scheme: https
        tls_config:
          ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
        bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
        kubernetes_sd_configs:
          - role: node
        relabel_configs:
          #- source_labels: [__address__]
          #  regex: '(.*):10250'
          #  replacement: '${1}:10255'
          #  target_label: __address__
        - action: labelmap
          regex: __meta_kubernetes_node_label_(.+)
        - target_label: __address__
          replacement: kubernetes.default.svc:443
        - source_labels: [__meta_kubernetes_node_name]
          regex: (.+)
          target_label: __metrics_path__
          replacement: /api/v1/nodes/${1}/proxy/metrics
      # https://github.com/prometheus/prometheus/blob/master/documentation/examples/prometheus-kubernetes.yml#L79
      - job_name: 'kubernetes-endpoints'
        kubernetes_sd_configs:
          - role: endpoints
        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: (https?)
          - 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

      # https://github.com/prometheus/prometheus/blob/master/documentation/examples/prometheus-kubernetes.yml#L119
      - job_name: 'kubernetes-services'
        metrics_path: /probe
        params:
          module: [http_2xx]
        kubernetes_sd_configs:
          - role: service
        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_namespace]
            target_label: kubernetes_namespace
          - source_labels: [__meta_kubernetes_service_name]
            target_label: kubernetes_name

      # https://github.com/prometheus/prometheus/blob/master/documentation/examples/prometheus-kubernetes.yml#L156
      - job_name: 'kubernetes-pods'
        kubernetes_sd_configs:
          - role: pod
        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
          - source_labels: [__meta_kubernetes_pod_container_port_number]
            action: keep
            regex: 9\d{3}

      - job_name: 'kubernetes-cadvisor'
        scheme: https
        tls_config:
          ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
        bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
        kubernetes_sd_configs:
          - role: node
        relabel_configs:
          - action: labelmap
          - action: labelmap
            regex: __meta_kubernetes_node_label_(.+)
          - target_label: __address__
            replacement: kubernetes.default.svc:443
          - source_labels: [__meta_kubernetes_node_name]
            regex: (.+)
            target_label: __metrics_path__
            replacement: /api/v1/nodes/${1}/proxy/metrics/cadvisor

---
apiVersion: v1
kind: ConfigMap
metadata:
  creationTimestamp: null
  name: prometheus-rules
  namespace: monitoring
data:
  cpu-usage.rules: |
    ALERT NodeCPUUsage
      IF (100 - (avg by (instance) (irate(node_cpu{name="node-exporter",mode="idle"}[5m])) * 100)) > 75
      FOR 2m
      LABELS {
        severity="page"
      }
      ANNOTATIONS {
        SUMMARY = "{{$labels.instance}}: High CPU usage detected",
        DESCRIPTION = "{{$labels.instance}}: CPU usage is above 75% (current value is: {{ $value }})"
      }
  instance-availability.rules: |
    ALERT InstanceDown
      IF up == 0
      FOR 1m
      LABELS { severity = "page" }
      ANNOTATIONS {
        summary = "Instance {{ $labels.instance }} down",
        description = "{{ $labels.instance }} of job {{ $labels.job }} has been down for more than 1 minute.",
      }
  low-disk-space.rules: |
    ALERT NodeLowRootDisk
      IF ((node_filesystem_size{mountpoint="/root-disk"} - node_filesystem_free{mountpoint="/root-disk"} ) / node_filesystem_size{mountpoint="/root-disk"} * 100) > 75
      FOR 2m
      LABELS {
        severity="page"
      }
      ANNOTATIONS {
        SUMMARY = "{{$labels.instance}}: Low root disk space",
        DESCRIPTION = "{{$labels.instance}}: Root disk usage is above 75% (current value is: {{ $value }})"
      }

    ALERT NodeLowDataDisk
      IF ((node_filesystem_size{mountpoint="/data-disk"} - node_filesystem_free{mountpoint="/data-disk"} ) / node_filesystem_size{mountpoint="/data-disk"} * 100) > 75
      FOR 2m
      LABELS {
        severity="page"
      }
      ANNOTATIONS {
        SUMMARY = "{{$labels.instance}}: Low data disk space",
        DESCRIPTION = "{{$labels.instance}}: Data disk usage is above 75% (current value is: {{ $value }})"
      }
  mem-usage.rules: |
    ALERT NodeSwapUsage
      IF (((node_memory_SwapTotal-node_memory_SwapFree)/node_memory_SwapTotal)*100) > 75
      FOR 2m
      LABELS {
        severity="page"
      }
      ANNOTATIONS {
        SUMMARY = "{{$labels.instance}}: Swap usage detected",
        DESCRIPTION = "{{$labels.instance}}: Swap usage usage is above 75% (current value is: {{ $value }})"
      }

    ALERT NodeMemoryUsage
      IF (((node_memory_MemTotal-node_memory_MemFree-node_memory_Cached)/(node_memory_MemTotal)*100)) > 75
      FOR 2m
      LABELS {
        severity="page"
      }
      ANNOTATIONS {
        SUMMARY = "{{$labels.instance}}: High memory usage detected",
        DESCRIPTION = "{{$labels.instance}}: Memory usage is above 75% (current value is: {{ $value }})"
      }

---
apiVersion: v1
kind: Secret
data:
  admin-password: YWRtaW4=
  admin-username: YWRtaW4=
metadata:
  name: grafana
  namespace: monitoring
type: Opaque
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: prometheus-core
  namespace: monitoring
  labels:
    app: prometheus
    component: core
spec:
  replicas: 1
  selector:
    matchLabels:
      app: prometheus
      component: core
  template:
    metadata:
      name: prometheus-main
      labels:
        app: prometheus
        component: core
    spec:
      serviceAccountName: prometheus-k8s
      containers:
      - name: prometheus
        #image: prom/prometheus:v1.7.0
        image: prom/prometheus:v1.7.0
        args:
          - '-storage.local.retention=12h'
          - '-storage.local.memory-chunks=500000'
          - '-config.file=/etc/prometheus/prometheus.yaml'
          - '-alertmanager.url=http://alertmanager:9093/'
        ports:
        - name: webui
          containerPort: 9090
        resources:
          requests:
            cpu: 500m
            memory: 500M
          limits:
            cpu: 500m
            memory: 500M
        volumeMounts:
        - name: config-volume
          mountPath: /etc/prometheus
        - name: rules-volume
          mountPath: /etc/prometheus-rules
      volumes:
      - name: config-volume
        configMap:
          name: prometheus-core
      - name: rules-volume
        configMap:
          name: prometheus-rules
---
apiVersion: v1
kind: Service
metadata:
  name: prometheus
  namespace: monitoring
  labels:
    app: prometheus
    component: core
  annotations:
    prometheus.io/scrape: 'true'
spec:
  type: NodePort
  ports:
    - port: 9090
      protocol: TCP
      name: webui
      nodePort: 30091
  selector:
    app: prometheus
    component: core
---