kubernetes运行应用Controller2之DaemonSet详解

kubernetes运行应用1之Deployment详解

 

查看daemonset

如下,k8s自身的 DaemonSet kube-flannel-ds和kube-proxy分别负责在每个结点上运行flannel和kube-proxy组件
daemonset在每个节点上最多只能运行一个副本。

[machangwei@mcwk8s-master ~]$ kubectl get daemonset 
No resources found in default namespace.
[machangwei@mcwk8s-master ~]$ kubectl get daemonset  --namespace=kube-system  
NAME              DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   NODE SELECTOR            AGE
kube-flannel-ds   3         3         1       3            1           <none>                   5d
kube-proxy        3         3         3       3            3           kubernetes.io/os=linux   5d
[machangwei@mcwk8s-master ~]$ kubectl get pod --namespace=kube-system  -o wide
NAME                                    READY   STATUS             RESTARTS          AGE   IP           NODE            NOMINATED NODE   READINESS GATES
coredns-6d8c4cb4d-cnj2t                 1/1     Running            0                 5d    10.244.0.2   mcwk8s-master   <none>           <none>
coredns-6d8c4cb4d-ngfm4                 1/1     Running            0                 5d    10.244.0.3   mcwk8s-master   <none>           <none>
etcd-mcwk8s-master                      1/1     Running            0                 5d    10.0.0.4     mcwk8s-master   <none>           <none>
kube-apiserver-mcwk8s-master            1/1     Running            1 (13h ago)       5d    10.0.0.4     mcwk8s-master   <none>           <none>
kube-controller-manager-mcwk8s-master   1/1     Running            5 (80m ago)       5d    10.0.0.4     mcwk8s-master   <none>           <none>
kube-flannel-ds-cn4m9                   0/1     CrashLoopBackOff   147 (3m51s ago)   12h   10.0.0.6     mcwk8s-node2    <none>           <none>
kube-flannel-ds-hpgkz                   1/1     Running            0                 5d    10.0.0.4     mcwk8s-master   <none>           <none>
kube-flannel-ds-nnjvj                   0/1     CrashLoopBackOff   185 (3m38s ago)   5d    10.0.0.5     mcwk8s-node1    <none>           <none>
kube-proxy-92g5c                        1/1     Running            0                 12h   10.0.0.6     mcwk8s-node2    <none>           <none>
kube-proxy-kk22j                        1/1     Running            0                 5d    172.16.0.5   mcwk8s-node1    <none>           <none>
kube-proxy-xjjgf                        1/1     Running            0                 5d    10.0.0.4     mcwk8s-master   <none>           <none>
kube-scheduler-mcwk8s-master            1/1     Running            5 (82m ago)       5d    10.0.0.4     mcwk8s-master   <none>           <none>
[machangwei@mcwk8s-master ~]$ 

学习kube-flannel-ds

截取部分:https://www.cnblogs.com/machangwei-8/p/15759077.html#_label7

apiVersion: apps/v1
kind: DaemonSet  #语法结构和Deployment几乎往前一样,只是将kind设为DaemonSet
metadata:
  name: kube-flannel-ds
  namespace: kube-system
  labels:
    tier: node
    app: flannel
spec:
  selector:
    matchLabels:
      app: flannel
  template:
    metadata:
      labels:
        tier: node
        app: flannel
    spec:
      hostNetwork: true #指定Pod直接使用的是Node网络,相当于docker run --network=host。
               #考虑到flannel需要为集群提供网络连接,这个要求是合理的
      initContainers:#定义了运行flannel服务的两个容器
      - name: install-cni-plugin
        image: rancher/mirrored-flannelcni-flannel-cni-plugin:v1.0.0
        command:
      containers:   #定义了运行flannel服务的两个容器
      - name: kube-flannel
        image: quay.io/coreos/flannel:v0.15.1
        command:
        - /opt/bin/flanneld
        args:
        - --ip-masq
        - --kube-subnet-mgr

学习kube-proxy,查看daemonset配置

[machangwei@mcwk8s-master ~]$ kubectl edit daemonset kube-proxy --namespace=kube-system

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: apps/v1
kind: DaemonSet #指定资源类型
metadata:
  annotations:
    deprecated.daemonset.template.generation: "1"
  creationTimestamp: "2022-01-12T15:15:18Z"
  generation: 1
  labels:
    k8s-app: kube-proxy
  name: kube-proxy
  namespace: kube-system
  resourceVersion: "18274"
  uid: 04cfea8d-94b3-4963-b8d2-b10a7b6a46b0
spec:
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: kube-proxy
  template:
    metadata:
      creationTimestamp: null
      labels:
        k8s-app: kube-proxy
    spec:
      containers:
      - command:
        - /usr/local/bin/kube-proxy
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: apps/v1
kind: DaemonSet   #指定资源类型
metadata:
  annotations:
    deprecated.daemonset.template.generation: "1"
  creationTimestamp: "2022-01-12T15:15:18Z"
  generation: 1
  labels:
    k8s-app: kube-proxy
  name: kube-proxy
  namespace: kube-system
  resourceVersion: "18274"
  uid: 04cfea8d-94b3-4963-b8d2-b10a7b6a46b0
spec:
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: kube-proxy
  template:
    metadata:
      creationTimestamp: null
      labels:
        k8s-app: kube-proxy
    spec:
      containers:  #定义kube-proxy的容器
      - command:
        - /usr/local/bin/kube-proxy
        - --config=/var/lib/kube-proxy/config.conf
        - --hostname-override=$(NODE_NAME)
        env:
        - name: NODE_NAME
          valueFrom:
            fieldRef:
              apiVersion: v1
              fieldPath: spec.nodeName
        image: registry.aliyuncs.com/google_containers/kube-proxy:v1.23.1
        imagePullPolicy: IfNotPresent
        name: kube-proxy
        resources: {}
        securityContext:
          privileged: true
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        volumeMounts:
        - mountPath: /var/lib/kube-proxy
          name: kube-proxy
        - mountPath: /run/xtables.lock
          name: xtables-lock
        - mountPath: /lib/modules
          name: lib-modules
          readOnly: true
      dnsPolicy: ClusterFirst
      hostNetwork: true
      nodeSelector:
        kubernetes.io/os: linux
      priorityClassName: system-node-critical
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      serviceAccount: kube-proxy
      serviceAccountName: kube-proxy
      terminationGracePeriodSeconds: 30
      tolerations:
      - operator: Exists
      volumes:
      - configMap:
          defaultMode: 420
          name: kube-proxy
        name: kube-proxy
      - hostPath:
          path: /run/xtables.lock
          type: FileOrCreate
        name: xtables-lock
      - hostPath:
          path: /lib/modules
          type: ""
        name: lib-modules
  updateStrategy:
    rollingUpdate:
      maxSurge: 0
      maxUnavailable: 1
    type: RollingUpdate
status:  #当前DamonSet的运行状态,这个部分是kubectl edit 特有的。其实kubernetes集群中每个当前运行的资源都
  currentNumberScheduled: 3 #可以通过kubectl edit 查看器配置和运行状态, 
  desiredNumberScheduled: 3 #比如: kubectl edit deployment mcwnginx-deployment
  numberAvailable: 3
  numberMisscheduled: 0
  numberReady: 3
  observedGeneration: 1
  updatedNumberScheduled: 3

[machangwei@mcwk8s-master ~]$ kubectl edit daemonset kube-proxy --namespace=kube-system #跟vim一样,q退出,如果修改了那么应该是wq吧
Edit cancelled, no changes made.

运行自己的DaemonSet失败

有时间再看这个失败问题,如果哪位大佬知道,指点下也好

[machangwei@mcwk8s-master ~]$ vim mcwJiankong.yml
[machangwei@mcwk8s-master ~]$ cat mcw
cat: mcw: No such file or directory
[machangwei@mcwk8s-master ~]$ cat mcw
mcwJiankong.yml  mcwNginx.yml     
[machangwei@mcwk8s-master ~]$ cat mcwJiankong.yml 
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: mcw-prometheus-node-daemonset
spec:
  replicas: 3
  selector:
    matchLabels:
     app: mcw_prometheus
  template:
    metadata:
      labels:
        app: mcw_prometheus
    spec:
      hostNetwork: true
      containers:
        - name: mcw-pr-node
          image: prom/node-exporter
          imagePullPolicy: IfNotPresent
          command:
          - /bin/node_exporter
          - --pathprocfs
          - /host/proc
          - --path.sysfs
          - /host/sys
          - --collector.filesystem.ignored-mount-points
          - ^/(sys|proc|dev|host|etc)($|/)
          volumeMounts:
          - name: proc
            mountPath: /host/proc
          - name: sys
            mountPath: /host/sys
          - name: root
            mountPath: /rootfs
      volumes:
      - name: proc
        hostPath:
          path: /proc
      - name: sys
        hostPath:
          path: /sys
      - name: root
        hostPath:
          path: /
[machangwei@mcwk8s-master ~]$ kubectl apply -f mcwJiankong.yml  #daemonset不能指定副本数量,好像每个节点都会运行,这里可能没包括主节点
error: error validating "mcwJiankong.yml": error validating data: ValidationError(DaemonSet.spec): unknown field "replicas" in io.k8s.api.apps.v1.DaemonSetSpec; if you choose to ignore these errors, turn validation off with --validate=false
[machangwei@mcwk8s-master ~]$ 
[machangwei@mcwk8s-master ~]$ vim mcwJiankong.yml
[machangwei@mcwk8s-master ~]$ cat mcwJiankong.yml  #去掉副本数
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: mcw-prometheus-node-daemonset
spec:
  selector:
    matchLabels:
     app: mcw_prometheus
  template:
    metadata:
      labels:
        app: mcw_prometheus
    spec:
      hostNetwork: true
      containers:
        - name: mcw-pr-node
          image: prom/node-exporter
          imagePullPolicy: IfNotPresent
          command:
          - /bin/node_exporter
          - --pathprocfs
          - /host/proc
          - --path.sysfs
          - /host/sys
          - --collector.filesystem.ignored-mount-points
          - ^/(sys|proc|dev|host|etc)($|/)
          volumeMounts:
          - name: proc
            mountPath: /host/proc
          - name: sys
            mountPath: /host/sys
          - name: root
            mountPath: /rootfs
      volumes:
      - name: proc
        hostPath:
          path: /proc
      - name: sys
        hostPath:
          path: /sys
      - name: root
        hostPath:
          path: /
[machangwei@mcwk8s-master ~]$ 
[machangwei@mcwk8s-master ~]$ 
[machangwei@mcwk8s-master ~]$ kubectl apply -f mcwJiankong.yml  
daemonset.apps/mcw-prometheus-node-daemonset created
[machangwei@mcwk8s-master ~]$ kubectl get daemonset #查看daemonset
NAME                            DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   NODE SELECTOR   AGE
mcw-prometheus-node-daemonset   2         2         0       2            0           <none>          19s
[machangwei@mcwk8s-master ~]$ kubectl get pod -o wide  #查看pod,结果未能成功运行。不清楚原因,有时间再看这个问题
NAME                                  READY   STATUS             RESTARTS      AGE   IP         NODE           NOMINATED NODE   READINESS GATES
mcw-prometheus-node-daemonset-cv8k2   0/1     CrashLoopBackOff   2 (17s ago)   60s   10.0.0.5   mcwk8s-node1   <none>           <none>
mcw-prometheus-node-daemonset-z2vvc   0/1     Error              2 (30s ago)   60s   10.0.0.6   mcwk8s-node2   <none>           <none>
[machangwei@mcwk8s-master ~]$ kubectl describe pod mcw-prometheus-node-daemonset-cv8k2
Name:         mcw-prometheus-node-daemonset-cv8k2
Namespace:    default
Priority:     0
Node:         mcwk8s-node1/10.0.0.5
Start Time:   Tue, 18 Jan 2022 00:34:32 +0800
Labels:       app=mcw_prometheus
              controller-revision-hash=7b99d77578
              pod-template-generation=1
Annotations:  <none>
Status:       Running
IP:           10.0.0.5
IPs:
  IP:           10.0.0.5
Controlled By:  DaemonSet/mcw-prometheus-node-daemonset
Containers:
  mcw-pr-node:
    Container ID:  docker://7ff049b0c303ebb997c4794c9ffadbe7520f8cfdba71caec3b6b32c193ea1369
    Image:         prom/node-exporter
    Image ID:      docker-pullable://prom/node-exporter@sha256:f2269e73124dd0f60a7d19a2ce1264d33d08a985aed0ee6b0b89d0be470592cd
    Port:          <none>
    Host Port:     <none>
    Command:
      /bin/node_exporter
      --pathprocfs
      /host/proc
      --path.sysfs
      /host/sys
      --collector.filesystem.ignored-mount-points
      ^/(sys|proc|dev|host|etc)($|/)
    State:          Waiting
      Reason:       CrashLoopBackOff
    Last State:     Terminated
      Reason:       Error
      Exit Code:    1
      Started:      Tue, 18 Jan 2022 00:36:24 +0800
      Finished:     Tue, 18 Jan 2022 00:36:24 +0800
    Ready:          False
    Restart Count:  4
    Environment:    <none>
    Mounts:
      /host/proc from proc (rw)
      /host/sys from sys (rw)
      /rootfs from root (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-w9bkl (ro)
Conditions:
  Type              Status
  Initialized       True 
  Ready             False 
  ContainersReady   False 
  PodScheduled      True 
Volumes:
  proc:
    Type:          HostPath (bare host directory volume)
    Path:          /proc
    HostPathType:  
  sys:
    Type:          HostPath (bare host directory volume)
    Path:          /sys
    HostPathType:  
  root:
    Type:          HostPath (bare host directory volume)
    Path:          /
    HostPathType:  
  kube-api-access-w9bkl:
    Type:                    Projected (a volume that contains injected data from multiple sources)
    TokenExpirationSeconds:  3607
    ConfigMapName:           kube-root-ca.crt
    ConfigMapOptional:       <nil>
    DownwardAPI:             true
QoS Class:                   BestEffort
Node-Selectors:              <none>
Tolerations:                 node.kubernetes.io/disk-pressure:NoSchedule op=Exists
                             node.kubernetes.io/memory-pressure:NoSchedule op=Exists
                             node.kubernetes.io/network-unavailable:NoSchedule op=Exists
                             node.kubernetes.io/not-ready:NoExecute op=Exists
                             node.kubernetes.io/pid-pressure:NoSchedule op=Exists
                             node.kubernetes.io/unreachable:NoExecute op=Exists
                             node.kubernetes.io/unschedulable:NoSchedule op=Exists
Events:
  Type     Reason     Age                 From               Message
  ----     ------     ----                ----               -------
  Normal   Scheduled  2m36s               default-scheduler  Successfully assigned default/mcw-prometheus-node-daemonset-cv8k2 to mcwk8s-node1
  Normal   Pulling    2m36s               kubelet            Pulling image "prom/node-exporter"
  Normal   Pulled     2m9s                kubelet            Successfully pulled image "prom/node-exporter" in 27.526626918s
  Normal   Created    45s (x5 over 2m9s)  kubelet            Created container mcw-pr-node
  Normal   Started    45s (x5 over 2m8s)  kubelet            Started container mcw-pr-node
  Normal   Pulled     45s (x4 over 2m8s)  kubelet            Container image "prom/node-exporter" already present on machine
  Warning  BackOff    31s (x9 over 2m7s)  kubelet            Back-off restarting failed container
[machangwei@mcwk8s-master ~]$ 

 

posted @ 2022-01-18 00:58  马昌伟  阅读(90)  评论(0编辑  收藏  举报