IoT邊緣集群Kubernetes?Events告警通知實現(xiàn)示例

更新時間：2023年02月17日 11:13:32 作者：東風微鳴

這篇文章主要為大家介紹了IoT邊緣集群Kubernetes?Events告警通知實現(xiàn)示例詳解，有需要的朋友可以借鑒參考下，希望能夠有所幫助，祝大家多多進步，早日升職加薪

背景

邊緣集群（基于樹莓派 + K3S) 需要實現(xiàn)基本的告警功能。

邊緣集群限制

CPU/內存/存儲資源緊張，無法支撐至少需要 2GB 以上內存和大量存儲的基于 Prometheus 的完整監(jiān)控體系方案（即使是基于 Prometheus Agent, 也無法支撐）（需要避免額外的存儲和計算資源消耗）

網絡條件，無法支撐監(jiān)控體系，因為監(jiān)控體系一般都需要每 1min 定時（或每時每刻）傳輸數(shù)據(jù)，且數(shù)據(jù)量不?。?/p>

存在 5G 收費網絡的情況，且訪問的目的端地址需要開通權限，且按照流量收費，且因為 5G 網絡條件，網絡傳輸能力受限，且不穩(wěn)定（可能會在一段時間內離線）;

關鍵需求

總結下來，關鍵需求如下：

實現(xiàn)對邊緣集群異常的及時告警，需要知道邊緣集群正在發(fā)生的異常情況；
網絡：網絡條件情況較差，網絡流量少，只只能開通極少數(shù)目的端地址，可以容忍網絡不穩(wěn)定（一段時間內離線）的情況；
資源：需要盡量避免額外的存儲和計算資源消耗

方案

綜上所訴，采用如下方案實現(xiàn)：

基于 Kubernetes Events 的告警通知

架構圖

技術方案規(guī)劃

從 Kubernetes 的各項資源收集 Events, 如：
pod

node

kubelet

crd

...
通過 kubernetes-event-exporter 組件來實現(xiàn)對 Kubernetes Events 的收集；
只篩選 Warning 級別 Events 供告警通知（后續(xù)，條件可以進一步定義）
告警通過飛書 webhook 等通信工具進行發(fā)送（后續(xù)，發(fā)送渠道可以增加）

實施步驟

手動方式：

在邊緣集群上，執(zhí)行如下操作：

1. 創(chuàng)建 roles

如下：

cat << _EOF_ | kubectl apply -f -
---
apiVersion: v1
kind: Namespace
metadata:
  name: monitoring
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: event-exporter-extra
rules:
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
      - list
      - watch
---
apiVersion: v1
kind: ServiceAccount
metadata:
  namespace: monitoring
  name: event-exporter
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: event-exporter
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: view
subjects:
  - kind: ServiceAccount
    namespace: monitoring
    name: event-exporter
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: event-exporter-extra
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: event-exporter-extra
subjects:
  - kind: ServiceAccount
    namespace: kube-event-export
    name: event-exporter
_EOF_

2. 創(chuàng)建 kubernetes-event-exporter config

如下：

cat &lt;&lt; _EOF_ | kubectl apply -f -
apiVersion: v1
kind: ConfigMap
metadata:
  name: event-exporter-cfg
  namespace: monitoring
data:
  config.yaml: |
    logLevel: error
    logFormat: json
    route:
      routes:
        - match:
            - receiver: "dump"      
        - drop:
            - type: "Normal"
          match:
            - receiver: "feishu"                     
    receivers:
      - name: "dump"
        stdout: {}
      - name: "feishu"
        webhook:
          endpoint: "https://open.feishu.cn/open-apis/bot/v2/hook/..."
          headers:
            Content-Type: application/json
          layout:
            msg_type: interactive
            card:
              config:
                wide_screen_mode: true
                enable_forward: true
              header:
                title:
                  tag: plain_text
                  content: XXX IoT K3S 集群告警
                template: red
              elements:
                - tag: div
                  text: 
                    tag: lark_md
                    content: "**EventType:**  {{ .Type }}\n**EventKind:**  {{ .InvolvedObject.Kind }}\n**EventReason:**  {{ .Reason }}\n**EventTime:**  {{ .LastTimestamp }}\n**EventMessage:**  {{ .Message }}"
_EOF_

?? 注意：

endpoint: "https://open.feishu.cn/open-apis/bot/v2/hook/..." 按需修改為對應的 webhook endpoint, ?切記勿對外公布！!!
content: XXX IoT K3S 集群告警: 按需調整為方便快速識別的名稱，如："家里測試 K3S 集群告警"

3. 創(chuàng)建 Deployment

cat &lt;&lt; _EOF_ | kubectl apply -f -
apiVersion: apps/v1
kind: Deployment
metadata:
  name: event-exporter
  namespace: monitoring
spec:
  replicas: 1
  selector:
    matchLabels:
      app: event-exporter
      version: v1
  template:
    metadata:
      labels:
        app: event-exporter
        version: v1
    spec:
      volumes:
        - name: cfg
          configMap:
            name: event-exporter-cfg
            defaultMode: 420
        - name: localtime
          hostPath:
            path: /etc/localtime
            type: ''
        - name: zoneinfo
          hostPath:
            path: /usr/share/zoneinfo
            type: ''
      containers:
        - name: event-exporter
          image: ghcr.io/opsgenie/kubernetes-event-exporter:v0.11
          args:
            - '-conf=/data/config.yaml'
          env:
            - name: TZ
              value: Asia/Shanghai
          volumeMounts:
            - name: cfg
              mountPath: /data
            - name: localtime
              readOnly: true
              mountPath: /etc/localtime
            - name: zoneinfo
              readOnly: true
              mountPath: /usr/share/zoneinfo
          imagePullPolicy: IfNotPresent
      serviceAccount: event-exporter
      affinity:
        nodeAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
            - weight: 100
              preference:
                matchExpressions:
                  - key: node-role.kubernetes.io/controlplane
                    operator: In
                    values:
                      - 'true'
            - weight: 100
              preference:
                matchExpressions:
                  - key: node-role.kubernetes.io/control-plane
                    operator: In
                    values:
                      - 'true'
            - weight: 100
              preference:
                matchExpressions:
                  - key: node-role.kubernetes.io/master
                    operator: In
                    values:
                      - 'true'    
      tolerations:
        - key: node-role.kubernetes.io/controlplane
          value: 'true'
          effect: NoSchedule
        - key: node-role.kubernetes.io/control-plane
          operator: Exists
          effect: NoSchedule
        - key: node-role.kubernetes.io/master
          operator: Exists
          effect: NoSchedule      
_EOF_

?? 說明：

event-exporter-cfg 相關配置，是用于加載以 ConfigMap 形式保存的配置文件；
localtime zoneinfo TZ 相關配置，是用于修改該 pod 的時區(qū)為Asia/Shanghai, 以使得最終顯示的通知效果為 CST 時區(qū)；
affinity tolerations 相關配置，是為了確保：無論如何，優(yōu)先調度到 master node 上去，按需調整，此處是因為 master 往往在邊緣集群中作為網關存在，配置較高，且在線時間較長；

自動化部署

效果：安裝 K3S 時就自動部署

在 K3S server 所在節(jié)點，/var/lib/rancher/k3s/server/manifests/ 目錄（如果沒有該目錄就先創(chuàng)建）下，創(chuàng)建 event-exporter.yaml

---
apiVersion: v1
kind: Namespace
metadata:
  name: monitoring
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: event-exporter-extra
rules:
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
      - list
      - watch
---
apiVersion: v1
kind: ServiceAccount
metadata:
  namespace: monitoring
  name: event-exporter
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: event-exporter
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: view
subjects:
  - kind: ServiceAccount
    namespace: monitoring
    name: event-exporter
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: event-exporter-extra
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: event-exporter-extra
subjects:
  - kind: ServiceAccount
    namespace: kube-event-export
    name: event-exporter
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: event-exporter-cfg
  namespace: monitoring
data:
  config.yaml: |
    logLevel: error
    logFormat: json
    route:
      routes:
        - match:
            - receiver: "dump"      
        - drop:
            - type: "Normal"
          match:
            - receiver: "feishu"                     
    receivers:
      - name: "dump"
        stdout: {}
      - name: "feishu"
        webhook:
          endpoint: "https://open.feishu.cn/open-apis/bot/v2/hook/dc4fd384-996b-4d20-87cf-45b3518869ec"
          headers:
            Content-Type: application/json
          layout:
            msg_type: interactive
            card:
              config:
                wide_screen_mode: true
                enable_forward: true
              header:
                title:
                  tag: plain_text
                  content: xxxK3S集群告警
                template: red
              elements:
                - tag: div
                  text: 
                    tag: lark_md
                    content: "**EventType:**  {{ .Type }}\n**EventKind:**  {{ .InvolvedObject.Kind }}\n**EventReason:**  {{ .Reason }}\n**EventTime:**  {{ .LastTimestamp }}\n**EventMessage:**  {{ .Message }}"
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: event-exporter
  namespace: monitoring
spec:
  replicas: 1
  selector:
    matchLabels:
      app: event-exporter
      version: v1
  template:
    metadata:
      labels:
        app: event-exporter
        version: v1
    spec:
      volumes:
        - name: cfg
          configMap:
            name: event-exporter-cfg
            defaultMode: 420
        - name: localtime
          hostPath:
            path: /etc/localtime
            type: ''
        - name: zoneinfo
          hostPath:
            path: /usr/share/zoneinfo
            type: ''
      containers:
        - name: event-exporter
          image: ghcr.io/opsgenie/kubernetes-event-exporter:v0.11
          args:
            - '-conf=/data/config.yaml'
          env:
            - name: TZ
              value: Asia/Shanghai
          volumeMounts:
            - name: cfg
              mountPath: /data
            - name: localtime
              readOnly: true
              mountPath: /etc/localtime
            - name: zoneinfo
              readOnly: true
              mountPath: /usr/share/zoneinfo
          imagePullPolicy: IfNotPresent
      serviceAccount: event-exporter
      affinity:
        nodeAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
            - weight: 100
              preference:
                matchExpressions:
                  - key: node-role.kubernetes.io/controlplane
                    operator: In
                    values:
                      - 'true'
            - weight: 100
              preference:
                matchExpressions:
                  - key: node-role.kubernetes.io/control-plane
                    operator: In
                    values:
                      - 'true'
            - weight: 100
              preference:
                matchExpressions:
                  - key: node-role.kubernetes.io/master
                    operator: In
                    values:
                      - 'true'    
      tolerations:
        - key: node-role.kubernetes.io/controlplane
          value: 'true'
          effect: NoSchedule
        - key: node-role.kubernetes.io/control-plane
          operator: Exists
          effect: NoSchedule
        - key: node-role.kubernetes.io/master
          operator: Exists
          effect: NoSchedule

之后啟動 K3S 就會自動部署。

???Reference: 自動部署 manifests 和 Helm charts | Rancher 文檔