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[CloudNative：KuberNetes&資源排程.V16]                                                               [Applications.KuberNetes] [|DevOps|k8s|資源排程|DaemonSet使用|DaemonSet更新和回滾|]

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一、DaemonSet概述

### --- DaemonSet是什麼？

~~~     DaemonSet：守護程序集，縮寫為ds，在所有節點或者是匹配的節點上都部署一個Pod。

### --- DaemonSet應用場景

~~~     執行叢集儲存的daemon，比如ceph或者glusterd
~~~     節點的CNI網路外掛，calico（在每個節點上充當路由器，去分發網路）
~~~     節點日誌的收集：fluentd或者是filebeat
~~~     節點的監控：node exporter
~~~     服務暴露：部署一個ingress nginx
 

二、建立DaemonSet

### --- 建立nginx-daemonset.yaml配置檔案
~~~     沒有副本數的概念，
~~~     灰度更新刪除掉

[root@k8s-master01 ~]# vim nginx-ds.yaml 
apiVersion: apps/v1
kind: DaemonSet
metadata:
  labels:
    app: nginx
  name: nginx
spec:
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx:1.15.2
        imagePullPolicy: IfNotPresent
        name: nginx
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
      dnsPolicy: ClusterFirst
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      terminationGracePeriodSeconds: 30
 

### --- 建立nginx-daemonset

~~~     # 建立nginx-daemonset.yaml
[root@k8s-master01 ~]# kubectl create -f nginx-ds.yaml 
daemonset.apps/nginx created

~~~     # 檢視建立的daemonset.pod

[root@k8s-master01 ~]# kubectl get node -owide
NAME           STATUS   ROLES    AGE   VERSION   INTERNAL-IP    EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION                CONTAINER-RUNTIME
k8s-master01   Ready    <none>   9d    v1.20.0   192.168.1.11   <none>        CentOS Linux 7 (Core)   4.19.12-1.el7.elrepo.x86_64   docker://19.3.15
k8s-master02   Ready    <none>   9d    v1.20.0   192.168.1.12   <none>        CentOS Linux 7 (Core)   4.19.12-1.el7.elrepo.x86_64   docker://19.3.15
k8s-master03   Ready    <none>   9d    v1.20.0   192.168.1.13   <none>        CentOS Linux 7 (Core)   4.19.12-1.el7.elrepo.x86_64   docker://19.3.15
k8s-node01     Ready    <none>   9d    v1.20.0   192.168.1.14   <none>        CentOS Linux 7 (Core)   4.19.12-1.el7.elrepo.x86_64   docker://19.3.15
k8s-node02     Ready    <none>   9d    v1.20.0   192.168.1.15   <none>        CentOS Linux 7 (Core)   4.19.12-1.el7.elrepo.x86_64   docker://19.3.15
 

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Walter Savage Landor:strove with none,for none was worth my strife.Nature I loved and, next to Nature, Art:I warm'd both hands before the fire of life.It sinks, and I am ready to depart                                                                                                                                                    ——W.S.Landor

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來自為知筆記(Wiz)